Merge branch 'stable-3.5' into stable-3.6

* stable-3.5:
  Set version to 3.5.6-SNAPSHOT
  Set version to 3.5.5
  GroupBackend: Provide a default isOrContainsExternalGroup
  Fix LabelPredicate group matching for included external groups
  ChangeQueryBuilder: De-dup parseGroup()
  ChangeQueryBuilder: containsExternalSubGroups fixup
  Fix ownerin/uploaderin for internal groups that include external groups
  Fix rendering String input values in plugin project options
  Update JGit to a1901305b
  Fix negated label: queries with external groups
  Fix documentation for 'secure-store-lib'
  Bump JGit to 801a56b48
  Bump sshd version to 2.9.2
  Bump SSHD version to 2.9.1
  Documentation: fixup ExternalId case insensitivity

Change-Id: I7412b04ea7a59f6fdaa9a661aee76460aee66919
Release-Notes: skip
diff --git a/.bazelrc b/.bazelrc
index b4eafb1..407b005 100644
--- a/.bazelrc
+++ b/.bazelrc
@@ -2,7 +2,30 @@
 build --repository_cache=~/.gerritcodereview/bazel-cache/repository
 build --action_env=PATH
 build --disk_cache=~/.gerritcodereview/bazel-cache/cas
-build --java_toolchain=//tools:error_prone_warnings_toolchain_java11
+
+# Builds using remotejdk_11, executes using remotejdk_11 or local_jdk
+build --java_language_version=11
+build --java_runtime_version=remotejdk_11
+build --tool_java_language_version=11
+build --tool_java_runtime_version=remotejdk_11
+
+# Builds using remotejdk_17, executes using remotejdk_17 or local_jdk
+build:java17 --java_language_version=17
+build:java17 --java_runtime_version=remotejdk_17
+build:java17 --tool_java_language_version=17
+build:java17 --tool_java_runtime_version=remotejdk_17
+
+# Builds and executes on RBE using remotejdk_11
+build:remote --java_language_version=11
+build:remote --java_runtime_version=remotejdk_11
+build:remote --tool_java_language_version=11
+build:remote --tool_java_runtime_version=remotejdk_11
+
+# Builds and executes on RBE using remotejdk_17
+build:remote17 --java_language_version=17
+build:remote17 --java_runtime_version=remotejdk_17
+build:remote17 --tool_java_language_version=17
+build:remote17 --tool_java_runtime_version=remotejdk_17
 
 # Enable strict_action_env flag to. For more information on this feature see
 # https://groups.google.com/forum/#!topic/bazel-discuss/_VmRfMyyHBk.
@@ -14,7 +37,6 @@
 build --announce_rc
 
 test --build_tests_only
-test --test_output=errors
-test --java_toolchain=//tools:error_prone_warnings_toolchain_java11
+test --test_output=all
 
 import %workspace%/tools/remote-bazelrc
diff --git a/.bazelversion b/.bazelversion
index af8c8ec..c7cb131 100644
--- a/.bazelversion
+++ b/.bazelversion
@@ -1 +1 @@
-4.2.2
+5.3.1
diff --git a/.gitignore b/.gitignore
index 95f94ba..8edc10e 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,4 +1,5 @@
 # Keep following lines sorted according to `LC_COLLATE=C sort`
+*.code-workspace
 *.eml
 *.iml
 *.log
diff --git a/BUILD b/BUILD
index 084d383..984fd955 100644
--- a/BUILD
+++ b/BUILD
@@ -4,24 +4,17 @@
 package(default_visibility = ["//visibility:public"])
 
 config_setting(
-    name = "java11",
+    name = "java17",
     values = {
-        "java_toolchain": "@bazel_tools//tools/jdk:toolchain_java11",
-    },
-)
-
-config_setting(
-    name = "java_next",
-    values = {
-        "java_toolchain": "//tools:toolchain_vanilla",
+        "java_language_version": "17",
     },
 )
 
 genrule(
     name = "gen_version",
     outs = ["version.txt"],
-    cmd = ("cat bazel-out/volatile-status.txt bazel-out/stable-status.txt | " +
-           "grep STABLE_BUILD_GERRIT_LABEL | cut -d ' ' -f 2 > $@"),
+    cmd = ("(cat bazel-out/volatile-status.txt bazel-out/stable-status.txt | " +
+           "grep STABLE_BUILD_GERRIT_LABEL | cut -d ' ' -f 2) > $@ || echo 'UNKNOWN' > $@"),
     stamp = 1,
 )
 
diff --git a/Documentation/cmd-copy-approvals.txt b/Documentation/cmd-copy-approvals.txt
deleted file mode 100644
index ba5344f..0000000
--- a/Documentation/cmd-copy-approvals.txt
+++ /dev/null
@@ -1,60 +0,0 @@
-= gerrit copy-approvals
-
-== NAME
-gerrit copy-approvals - Copy all inferred approvals labels to the latest patch-set.
-
-== SYNOPSIS
-[verse]
---
-_ssh_ -p <port> <host> _gerrit copy-approvals_
-  [--verbose | -v]
-  [PROJECT]...
---
-
-== DESCRIPTION
-Gerrit has historically computed votes using an inference algorithm that
-was cumulating them from all the patch-sets. That was not efficient since
-it had to take into account copied votes from very old patchsets.
-E.g, votes sometimes need to be copied from ps1 to ps10.
-
-Gerrit copy the approvals from the inferred votes to the latest patch-sets
-once a change receives a new label update.
-
-The copy-approval command scans all the changes of a project and looks for
-all votes that have not been copied yet, calculate the inferred score and
-apply that as copied label to the latest patch-set.
-
-NOTE: The label copied as part of this process receives the grant date of
-the timestamp of the copy-approval command execution, not the one associated
-with the inferred vote.
-
-== OPTIONS
-
---verbose::
--v::
-	Display projects/changes impacted by the label copy operation.
-
-== ACCESS
-Only the user with MAINTAIN_SERVER permissions can run this command.
-
-== SCRIPTING
-This command is intended to be used in scripts.
-
-== EXAMPLES
-
-Copy all inferred labels on the project 'foo'
-----
-$ ssh -p 29418 review.example.com gerrit copy-approvals foo
-----
-
-Copy all inferred labels on all projects
-----
-$ ssh -p 29418 review.example.com gerrit copy-approvals
-----
-
-GERRIT
-------
-Part of link:index.html[Gerrit Code Review]
-
-SEARCHBOX
----------
diff --git a/Documentation/concept-patch-sets.txt b/Documentation/concept-patch-sets.txt
index 274fbb0..e39d091 100644
--- a/Documentation/concept-patch-sets.txt
+++ b/Documentation/concept-patch-sets.txt
@@ -88,8 +88,8 @@
 evolves, such as "Added more unit tests." Unlike the change description, a patch
 set description does not become a part of the project's history.
 
-To add a patch set description, click *Add a patch set description*, located in
-the file list, or provide it link:user-upload.html#patch_set_description[on upload].
+To add a patch set description provide it
+link:user-upload.html#patch_set_description[on upload].
 
 GERRIT
 ------
diff --git a/Documentation/config-gerrit.txt b/Documentation/config-gerrit.txt
index 706a460..ced35e7 100644
--- a/Documentation/config-gerrit.txt
+++ b/Documentation/config-gerrit.txt
@@ -975,12 +975,6 @@
 +
 If direct updates are made to `All-Users`, this cache should be flushed.
 
-cache `"approvals"`::
-+
-Cache entries contain approvals for a given patch set. This includes
-approvals granted on this patch set as well as approvals copied from
-earlier patch sets.
-
 cache `"adv_bases"`::
 +
 Used only for push over smart HTTP when branch level access controls
@@ -1074,12 +1068,6 @@
 away from the defaults. The cache may be persisted by setting
 `diskLimit`, which is only recommended if cold start performance is
 problematic.
-+
-`external_ids_map` supports computing the new cache value based on a
-previously cached state. This applies modifications based on the Git
-diff and is almost always faster.
-`cache.external_ids_map.enablePartialReloads` turns this behavior on
-or off. The default is `true`.
 
 cache `"git_tags"`::
 +
@@ -1226,6 +1214,14 @@
 Result of checking if one change or commit is a pure/clean revert of
 another.
 
+cache `"soy_sauce_compiled_templates"`::
++
+Caches compiled soy templates. Stores at most only one key-value pair with
+a constant key value and the value is a compiled SoySauce templates. The value
+is reloaded automatically every few seconds if there are reads from the cache.
+If cache is not used for 1 minute, the item is removed (i.e. emails can be send
+with templates which are max 1 minute old).
+
 cache `"sshkeys"`::
 +
 Caches unpacked versions of user SSH keys, so the internal SSH daemon
@@ -2069,6 +2065,14 @@
 +
 Default is 1 hour.
 
+[[dashboard]]
+=== Section dashboard
+
+[[dashboard.submitRequirementColumns]]dashboard.submitRequirementColumns::
++
+The list of submit requirement names that should be displayed as separate
+columns in the dashboard.
+
 [[download]]
 === Section download
 
@@ -4982,16 +4986,6 @@
   replicate = replication start
 ----
 
-[[ssh]]
-=== Section ssh
-
-[[ssh.clientImplementation]]ssh.clientImplementation::
-+
-JCraft JSch client is supported in addition to Apache MINA SSH client.
-To use JSch client set the value to `JSCH`.
-+
-By default, `APACHE`.
-
 [[sshd]]
 === Section sshd
 
@@ -5212,22 +5206,27 @@
 +
 Supported ciphers:
 +
-* `aes128-ctr`
-* `aes192-ctr`
-* `aes256-ctr`
 * `aes128-cbc`
+* `aes128-ctr`
+* `aes128-gcm@openssh.com`
 * `aes192-cbc`
+* `aes192-ctr`
 * `aes256-cbc`
-* `blowfish-cbc`
-* `3des-cbc`
+* `aes256-ctr`
+* `aes256-gcm@openssh.com`
 * `arcfour128`
 * `arcfour256`
+* `blowfish-cbc`
+* `chacha20-poly1305@openssh.com`
+* `3des-cbc`
 * `none`
 +
-By default, all supported ciphers except `none` are available.
-+
 If your setup allows for it, it's recommended to disable all ciphers except
 the AES-CTR modes.
++
+See also link:https://github.com/apache/mina-sshd/tree/master#ciphers[ciphers,role=external,window=_blank].
++
+By default, all supported ciphers except `none` are available.
 
 [[sshd.mac]]sshd.mac::
 +
@@ -5245,6 +5244,11 @@
 * `hmac-sha1-96`
 * `hmac-sha2-256`
 * `hmac-sha2-512`
+* `hmac-sha1-etm@openssh.com`
+* `hmac-sha2-256-etm@openssh.com`
+* `hmac-sha2-512-etm@openssh.com`
++
+See also link:https://github.com/apache/mina-sshd/tree/master#macs[macs,role=external,window=_blank].
 +
 By default, all supported MACs are available.
 
@@ -5273,6 +5277,9 @@
 * `ecdh-sha2-nistp521`
 * `ecdh-sha2-nistp384`
 * `ecdh-sha2-nistp256`
+* `curve25519-sha256`
+* `curve25519-sha256@libssh.org`
+* `curve448-sha512`
 * `diffie-hellman-group-exchange-sha256`
 * `diffie-hellman-group18-sha512`
 * `diffie-hellman-group17-sha512`
@@ -5283,12 +5290,14 @@
 See link:#sshd.enableDeprecatedKexAlgorithms[sshd.enableDeprecatedKexAlgorithms]
 for deprecated key algorithms and how to enable them.
 
-By default, all supported key exchange algorithms are available.
-
 It is strongly recommended to disable at least `diffie-hellman-group1-sha1`
 as it's known to be vulnerable (logjam attack). Additionally, if your setup
 allows for it, it is recommended to disable the remaining two `sha1` key
 exchange algorithms.
+
+See also link:https://github.com/apache/mina-sshd/tree/master#key-exchange[key exchange,role=external,window=_blank].
+
+By default, all supported key exchange algorithms are available.
 --
 
 [[sshd.kerberosKeytab]]sshd.kerberosKeytab::
diff --git a/Documentation/config-labels.txt b/Documentation/config-labels.txt
index 5889c75..3fa84b1 100644
--- a/Documentation/config-labels.txt
+++ b/Documentation/config-labels.txt
@@ -6,7 +6,10 @@
 link:access-control.html#category_review_labels[access controls].  Gerrit
 comes pre-configured with the Code-Review label that can be granted to
 groups within projects, enabling functionality for that group's members.
-
+Project owners and admins might also need to configure rules which require
+labels to be voted before a change can be submittable. See the
+link:config-submit-requirements.html[submit requirements] documentation to
+configure such rules.
 
 [[label_Code-Review]]
 == Label: Code-Review
@@ -18,7 +21,7 @@
 
 The range of values is:
 
-* -2 This shall not be merged
+* -2 This shall not be submitted
 +
 The code is so horribly incorrect/buggy/broken that it must not be
 submitted to this project, or to this branch.  This value is valid
@@ -28,7 +31,7 @@
 +
 *Any -2 blocks submit.*
 
-* -1 I would prefer this is not merged as is
+* -1 I would prefer this is not submitted as is
 +
 The code doesn't look right, or could be done differently, but
 the reviewer is willing to live with it as-is if another reviewer
@@ -61,8 +64,8 @@
 
 For a change to be submittable, the latest patch set must have a
 `+2 Looks good to me, approved` in this category, and no
-`-2 Do not submit`.  Thus `-2` on any patch set can block a submit,
-while `+2` on the latest patch set can enable it.
+`-2 This shall not be submitted`.  Thus `-2` on any patch set can
+block a submit, while `+2` on the latest patch set can enable it.
 
 If a Gerrit installation does not wish to use this label in any project,
 the `[label "Code-Review"]` section can be deleted from `project.config`
@@ -97,7 +100,7 @@
       value = -1 Fails
       value = 0 No score
       value = +1 Verified
-      copyAllScoresIfNoCodeChange = true
+      copyCondition = changekind:NO_CODE_CHANGE
 ----
 
 The range of values is:
@@ -176,6 +179,11 @@
 The name for a label, consisting only of alphanumeric characters and
 `-`.
 
+[[label_description]]
+=== `label.Label-Name.description`
+
+The label description. This field can provide extra information of what the
+label is supposed to do.
 
 [[label_value]]
 === `label.Label-Name.value`
@@ -200,7 +208,12 @@
 
 
 [[label_function]]
-=== `label.Label-Name.function`
+=== `label.Label-Name.function (deprecated)`
+
+Label functions dictate the rules for requiring certain label votes before a
+change is allowed for submission. Label functions are **deprecated**, favour
+using link:config-submit-requirements.html[submit requirements] instead,
+except if it's needed to set the value to `PatchSetLock`.
 
 The name of a function for evaluating multiple votes for a label.  This
 function is only applied if the default submit rule is used for a label.
@@ -265,6 +278,9 @@
 [[label_copyAnyScore]]
 === `label.Label-Name.copyAnyScore`
 
+*DEPRECATED: use `is:ANY` predicate in
+link:config-labels.html#label_copyCondition[copyCondition] instead*
+
 If true, any score for the label is copied forward when a new patch
 set is uploaded. Defaults to false.
 
@@ -284,29 +300,37 @@
 
 Matches if the diff between two patch sets was of a certain change kind.
 
+`REWORK` matches all kind of change kinds because any other change kind
+is just a more trivial version of a rework. This means setting
+`changekind:REWORK` is equivalent to setting `is:ANY`.
+
+`NO_CHANGE` is more trivial than a trivial rebase, no code change and
+a first parent update, hence this change kind is also matched by
+`changekind:TRIVIAL_REBASE`, `changekind:NO_CODE_CHANGE` and
+`changekind:MERGE_FIRST_PARENT_UPDATE` (only if the change is for a
+merge commit).
+
 ==== is:{MIN,MAX,ANY}
 
 Matches votes that are equal to the minimal or maximal voting range. Or any votes.
 
-==== approverin:link:rest-api-groups.html#group-id[\{group-id\}]
+==== is:'VALUE'
+
+Matches approvals that have a voting value that is equal to 'VALUE'.
+
+Negative values need to be quoted, e.g.: is:"-1"
+
+[[approverin]]
+==== approverin:link:#group-id[\{group-id\}]
 
 Matches votes granted by a user who is a member of
-link:rest-api-groups.html#group-id[\{group-id\}].
+link:#group-id[\{group-id\}].
 
-Avoid using a group name with spaces (if it has spaces, use the group uuid).
-Although supported for convenience, it's better to use group uuid than group
-name since using names only works as long as the names are unique (and future
-groups with the same name will break the query).
+[[uploaderin]]
+==== uploaderin:link:#group-id[\{group-id\}]
 
-==== uploaderin:link:rest-api-groups.html#group-id[\{group-id\}]
-
-Matches votes where the new patch set was uploaded by a member of
-link:rest-api-groups.html#group-id[\{group-id\}].
-
-Avoid using a group name with spaces (if it has spaces, use the group uuid).
-Although supported for convenience, it's better to use group uuid than group
-name since using names only works as long as the names are unique (and future
-groups with the same name will break the query).
+Matches all votes if the new patch set was uploaded by a member of
+link:#group-id[\{group-id\}].
 
 ==== has:unchanged-files
 
@@ -314,6 +338,29 @@
 
 Only 'unchanged-files' is supported for 'has'.
 
+[[group-id]]
+==== Group ID
+
+Some predicates (link:#approverin[approverin], link:#uploaderin[uploaderin])
+expect a group ID as value. This group ID can be any of the
+link:rest-api-groups.html#group-id[group identifiers] that are supported in the
+REST API: group UUID, group ID (for Gerrit internal groups only) and group name
+
+It's preferred to reference groups by UUID, rather than name. Referencing
+groups by name is not recommended because:
+
+* Groups may be renamed and then the group reference can no longer be resolved.
+  If this happens another group with different members can take over the group
+  name, so that exemptions which have been granted by this predicate apply to
+  the other group. This is a security concern.
+* Group names that contain spaces are not supported.
+* Ambiguous group names cannot be resolved. This means if another group with
+  the same name gets created at a later point in time, the group name can no
+  longer be resolved and the predicate breaks.
+
+Using the group UUID has a small drawback though, since it makes the condition
+less human-readable.
+
 ==== Example
 
 ----
@@ -323,6 +370,9 @@
 [[label_copyMinScore]]
 === `label.Label-Name.copyMinScore`
 
+*DEPRECATED: use `is:MIN` predicate in
+link:config-labels.html#label_copyCondition[copyCondition] instead*
+
 If true, the lowest possible negative value for the label is copied
 forward when a new patch set is uploaded. Defaults to false, except
 for All-Projects which has it true by default.
@@ -330,6 +380,9 @@
 [[label_copyMaxScore]]
 === `label.Label-Name.copyMaxScore`
 
+*DEPRECATED: use `is:MAX` predicate in
+link:config-labels.html#label_copyCondition[copyCondition] instead*
+
 If true, the highest possible positive value for the label is copied
 forward when a new patch set is uploaded. This can be used to enable
 sticky approvals, reducing turn-around for trivial cleanups prior to
@@ -338,6 +391,9 @@
 [[label_copyAllScoresIfListOfFilesDidNotChange]]
 === `label.Label-Name.copyAllScoresIfListOfFilesDidNotChange`
 
+*DEPRECATED: use `is:ANY AND has:unchanged-files` predicates in
+link:config-labels.html#label_copyCondition[copyCondition] instead*
+
 This policy is useful if you don't want to trigger CI or human
 verification again if the list of files didn't change.
 
@@ -354,6 +410,9 @@
 [[label_copyAllScoresOnMergeFirstParentUpdate]]
 === `label.Label-Name.copyAllScoresOnMergeFirstParentUpdate`
 
+*DEPRECATED: use `is:ANY AND changekind:MERGE_FIRST_PARENT_UPDATE` predicates
+in link:config-labels.html#label_copyCondition[copyCondition] instead*
+
 This policy is useful if you don't want to trigger CI or human
 verification again if your target branch moved on but the feature
 branch being merged into the target branch did not change. It only
@@ -371,6 +430,9 @@
 [[label_copyAllScoresOnTrivialRebase]]
 === `label.Label-Name.copyAllScoresOnTrivialRebase`
 
+*DEPRECATED: use `is:ANY AND changekind:TRIVIAL_REBASE` predicates
+in link:config-labels.html#label_copyCondition[copyCondition] instead*
+
 If true, all scores for the label are copied forward when a new patch set is
 uploaded that is a trivial rebase. A new patch set is considered to be trivial
 rebase if the commit message is the same as in the previous patch set and if it
@@ -388,6 +450,9 @@
 [[label_copyAllScoresIfNoCodeChange]]
 === `label.Label-Name.copyAllScoresIfNoCodeChange`
 
+*DEPRECATED: use `is:ANY AND changekind:NO_CODE_CHANGE` predicates in
+link:config-labels.html#label_copyCondition[copyCondition] instead*
+
 If true, all scores for the label are copied forward when a new patch set is
 uploaded that has the same parent tree as the previous patch set and the same
 code diff (including context lines) as the previous patch set. This means only
@@ -402,6 +467,9 @@
 [[label_copyAllScoresIfNoChange]]
 === `label.Label-Name.copyAllScoresIfNoChange`
 
+*DEPRECATED: use `is:ANY AND changekind:NO_CHANGE` predicates in
+link:config-labels.html#label_copyCondition[copyCondition] instead*
+
 If true, all scores for the label are copied forward when a new patch
 set is uploaded that has the same parent tree, code delta, and commit
 message as the previous patch set. This means that only the patch
@@ -415,6 +483,9 @@
 [[label_copyValue]]
 === `label.Label-Name.copyValue`
 
+*DEPRECATED: use `is:<value>` predicate in
+link:config-labels.html#label_copyCondition[copyCondition] instead*
+
 Value that should be copied forward when a new patch set is uploaded.
 This can be used to enable sticky votes. Can be specified multiple
 times. By default not set.
@@ -457,7 +528,7 @@
 `${shardeduserid}`.
 
 [[label_ignoreSelfApproval]]
-=== `label.Label-Name.ignoreSelfApproval`
+=== `label.Label-Name.ignoreSelfApproval (deprecated)`
 
 If true, the label may be voted on by the uploader of the latest patch set,
 but their approval does not make a change submittable. Instead, a
@@ -465,6 +536,13 @@
 
 Defaults to false.
 
+The `ignoreSelfApproval` attribute is **deprecated**, favour
+using link:config-submit-requirements.html[submit requirements] and
+define the `submittableIf` expression with the `label` operator and
+the `user=non_uploader` argument. See the
+link:config-submit-requirements.html#code-review-example[Code Review] submit
+requirement example.
+
 [[label_example]]
 === Example
 
diff --git a/Documentation/config-mail.txt b/Documentation/config-mail.txt
index 029877b..8bd5dc7 100644
--- a/Documentation/config-mail.txt
+++ b/Documentation/config-mail.txt
@@ -226,6 +226,10 @@
 The original subject limited to 72 characters, with an ellipsis if it exceeds
 that.
 
+$change.sizeBucket::
++
+Human-readable size bucket of the current change.
+
 $change.ownerEmail::
 +
 The email address of the owner of the change.
diff --git a/Documentation/config-project-config.txt b/Documentation/config-project-config.txt
index 4dff685..9fd5b1b 100644
--- a/Documentation/config-project-config.txt
+++ b/Documentation/config-project-config.txt
@@ -142,7 +142,7 @@
 [[receive.requireContributorAgreement]]receive.requireContributorAgreement::
 +
 Controls whether or not a user must complete a contributor agreement before
-they can upload changes. Default is `INHERIT`. If `All-Project` enables this
+they can upload changes. Default is `INHERIT`. If `All-Projects` enables this
 option then the dependent project must set it to false if users are not
 required to sign a contributor agreement prior to submitting changes for that
 specific project. To use that feature the global option in `gerrit.config`
@@ -481,6 +481,12 @@
 
 Please refer to link:config-labels.html#label_custom[Custom Labels] documentation.
 
+[[submit-requirement-section]]
+=== Submit Requirement section
+
+Please refer to link:config-submit-requirements.html[Configuring Submit
+Requirements] documentation.
+
 [[branchOrder-section]]
 === branchOrder section
 
@@ -526,7 +532,7 @@
 A boolean indicating if reviewers and CCs that do not currently have a Gerrit
 account can be added to a change by providing their email address.
 +
-This setting only takes affect for changes that are readable by anonymous users.
+This setting only takes effect for changes that are readable by anonymous users.
 +
 Default is `INHERIT`, which means that this property is inherited from
 the parent project. If the property is not set in any parent project, the
diff --git a/Documentation/config-submit-requirements.txt b/Documentation/config-submit-requirements.txt
new file mode 100644
index 0000000..2686f39
--- /dev/null
+++ b/Documentation/config-submit-requirements.txt
@@ -0,0 +1,308 @@
+= Gerrit Code Review - Submit Requirements
+
+As part of the code review process, project owners need to configure rules that
+govern when changes become submittable. For example, an admin might want to
+prevent changes from being submittable until at least a “+2” vote on the
+“Code-Review” label is granted on a change. Admins can define submit
+requirements to enforce submittability rules for changes.
+
+[[configuring_submit_requirements]]
+== Configuring Submit Requirements
+
+Site administrators and project owners can define submit requirements in the
+link:config-project-config.html[project config]. A submit requirement has the
+following fields:
+
+
+[[submit_requirement_name]]
+=== submit-requirement.Name
+
+A name that uniquely identifies the submit requirement. Submit requirements
+can be overridden in child projects if they are defined with the same name in
+the child project. See the link:#inheritance[inheritance] section for more
+details.
+
+[[submit_requirement_description]]
+=== submit-requirement.Name.description
+
+A detailed description of what the submit requirement is supposed to do. This
+field is optional. The description is visible to the users in the change page
+upon hovering on the submit requirement to help them understand what the
+requirement is about and how it can be fulfilled.
+
+[[submit_requirement_applicable_if]]
+=== submit-requirement.Name.applicableIf
+
+A link:#query_expression_syntax[query expression] that determines if the submit
+requirement is applicable for a change. For example, administrators can exclude
+submit requirements for certain branch patterns. See the
+link:#exempt-branch-example[exempt branch] example.
+
+This field is optional, and if not specified, the submit requirement is
+considered applicable for all changes in the project.
+
+[[submit_requirement_submittable_if]]
+=== submit-requirement.Name.submittableIf
+
+A link:#query_expression_syntax[query expression] that determines when the
+change becomes submittable. This field is mandatory.
+
+
+[[submit_requirement_override_if]]
+=== submit-requirement.Name.overrideIf
+
+A link:#query_expression_syntax[query expression] that controls when the
+submit requirement is overridden. When this expression is evaluated to true,
+the submit requirement state becomes `OVERRIDDEN` and the submit requirement
+is no longer blocking the change submission.
+This expression can be used to enable bypassing the requirement in some
+circumstances, for example if the change owner is a power user or to allow
+change submission in case of emergencies. +
+
+This field is optional.
+
+[[submit_requirement_can_override_in_child_projects]]
+=== submit-requirement.Name.canOverrideInChildProjects
+
+A boolean (true, false) that determines if child projects can override the
+submit requirement. +
+
+The default value is `false`.
+
+[[evaluation_results]]
+== Evaluation Results
+
+When submit requirements are configured, their results are returned for all
+changes requested by the REST API with the
+link:rest-api-changes.html#submit-requirement-result-info[SubmitRequirementResultInfo]
+entity. +
+
+Submit requirement results are produced from the evaluation of the submit
+requirements in the project config (
+See link:#configuring_submit_requirements[Configuring Submit Requirements])
+as well as the conversion of the results of the legacy submit rules to submit
+requirement results. Legacy submit rules are label functions
+(see link:config-labels.html[config labels]), custom and
+link:prolog-cookbook.html[prolog] submit rules.
+
+The `status` field can be one of:
+
+* `NOT_APPLICABLE`
++
+The link:#submit_requirement_applicable_if[applicableIf] expression evaluates
+to false for the change.
+
+* `UNSATISFIED`
++
+The submit requirement is applicable
+(link:#submit_requirement_applicable_if[applicableIf] evaluates to true), but
+the evaluation of the link:#submit_requirement_submittable_if[submittableIf] and
+link:#submit_requirement_override_if[overrideIf] expressions return false for
+the change.
+
+* `SATISFIED`
++
+The submit requirement is applicable
+(link:#submit_requirement_applicable_if[applicableIf] evaluates to true), the
+link:#submit_requirement_submittable_if[submittableIf] expression evaluates to
+true, and the link:#submit_requirement_override_if[overrideIf] evaluates to
+false for the change.
+
+* `OVERRIDDEN`
++
+The submit requirement is applicable
+(link:#submit_requirement_applicable_if[applicableIf] evaluates to true) and the
+link:#submit_requirement_override_if[overrideIf] expression evaluates to true.
++
+Note that in this case, the change is overridden whether the
+link:#submit_requirement_submittable_if[submittableIf] expression evaluates to
+true or not.
+
+* `BYPASSED`
++
+The change was merged directly bypassing code review by supplying the
+link:user-upload.html#auto_merge[submit] push option while doing a git push.
+
+* `ERROR`
++
+The evaluation of any of the
+link:#submit_requirement_applicable_if[applicableIf],
+link:#submit_requirement_submittable_if[submittableIf] or
+link:#submit_requirement_override_if[overrideIf] expressions resulted in an
+error.
+
+
+[[query_expression_syntax]]
+== Query Expression Syntax
+
+All applicableIf, submittableIf and overrideIf expressions use the same syntax
+and operators available for link:user-search.html[searching changes]. In
+addition to that, submit requirements support extra operators.
+
+
+[[submit_requirements_operators]]
+=== Submit Requirements Operators
+
+[[operator_authoremail]]
+authoremail:'EMAIL_PATTERN'::
++
+An operator that returns true if the change author's email address matches a
+specific regular expression pattern. The
+link:http://www.brics.dk/automaton/[dk.brics.automaton library,role=external,window=_blank]
+is used for the evaluation of such patterns.
+
+[[operator_distinctvoters]]
+distinctvoters:'[Label1,Label2,...,LabelN],value=MAX,count>1'::
++
+An operator that allows checking for distinct voters across more than one label.
++
+2..N labels are supported, filtering by a value (MIN,MAX,integer) is optional.
+Count is mandatory.
++
+Examples:
+`distinctvoters:[Code-Review,Trust],value=MAX,count>1`
++
+`distinctvoters:[Code-Review,Trust,API-Review],count>2`
+
+[[operator_is_true]]
+is:true::
++
+An operator that always returns true for all changes. An example usage is to
+redefine a submit requirement in a child project and make the submit requirement
+always applicable.
+
+[[operator_is_false]]
+is:false::
++
+An operator that always returns false for all changes. An example usage is to
+redefine a submit requirement in a child project and make the submit requirement
+always non-applicable.
+
+[[operator_file]]
+file:"'<filePattern>',withDiffContaining='<contentPattern>'"::
++
+An operator that returns true if the latest patchset contained a modified file
+matching `<filePattern>` with a modified region matching `<contentPattern>`.
+
+[[unsupported_operators]]
+=== Unsupported Operators
+
+Some operators are not supported with submit requirement expressions.
+
+[[operator_is_submittable]]
+is:submittable::
++
+Cannot be used since it will result in recursive evaluation of expressions.
+
+[[inheritance]]
+== Inheritance
+
+Child projects can override a submit requirement defined in any of their parent
+projects. Overriding a submit requirement overrides all of its properties and
+values. The overriding project needs to define all mandatory fields.
+
+Submit requirements are looked up from the current project up the inheritance
+hierarchy to “All-Projects”. The first project in the hierarchy chain that sets
+link:#submit_requirement_can_override_in_child_projects[canOverrideInChildProjects]
+to false prevents all descendant projects from overriding it.
+
+If a project disallows a submit requirement from being overridden in child
+projects, all definitions of this submit requirement in descendant projects are
+ignored.
+
+To remove a submit requirement in a child project, administrators can redefine
+the requirement with the same name in the child project and set the
+link:#submit_requirement_applicable_if[applicableIf] expression to `is:false`.
+Since the link:#submit_requirement_submittable_if[submittableIf] field is
+mandatory, administrators need to provide it in the child project but can set it
+to anything, for example `is:false` but it will have no effect anyway.
+
+
+[[trigger-votes]]
+== Trigger Votes
+
+Trigger votes are label votes that are not associated with any submit
+requirement expressions. Trigger votes are displayed in a separate section in
+the change page. For more about configuring labels, see the
+link:config-labels.html[config labels] documentation.
+
+
+[[examples]]
+== Examples
+
+[[code-review-example]]
+=== Code-Review Example
+
+To define a submit requirement for code-review that requires a maximum vote for
+the “Code-Review” label from a non-uploader without a maximum negative vote:
+
+----
+[submit-requirement "Code-Review"]
+	description = A maximum vote from a non-uploader is required for the \
+	              'Code-Review' label. A minimum vote is blocking.
+	submittableIf = label:Code-Review=MAX,user=non_uploader AND -label:Code-Review=MIN
+	canOverrideInChildProjects = true
+----
+
+[[exempt-branch-example]]
+=== Exempt a branch Example
+
+We could exempt a submit requirement from certain branches. For example,
+project owners might want to skip the 'Code-Style' requirement from the
+refs/meta/config branch.
+
+----
+[submit-requirement "Code-Style"]
+  description = Code is properly styled and formatted
+  applicableIf = -branch:refs/meta/config
+  submittableIf = label:Code-Style=+1 AND -label:Code-Style=-1
+  canOverrideInChildProjects = true
+----
+
+
+[[test-submit-requirements]]
+== Testing Submit Requirements
+
+The link:rest-api-changes.html#check-submit-requirement[Check Submit Requirement]
+change endpoint can be used to test submit requirements on any change. Users
+are encouraged to test submit requirements before adding them to the project
+to ensure they work as intended.
+
+.Request
+----
+  POST /changes/myProject~master~I8473b95934b5732ac55d26311a706c9c2bde9940/check.submit_requirement HTTP/1.0
+  Content-Type: application/json; charset=UTF-8
+
+    {
+      "name": "Code-Review",
+      "submittability_expression": "label:Code-Review=+2"
+    }
+----
+
+.Response
+----
+  HTTP/1.1 200 OK
+  Content-Disposition: attachment
+  Content-Type: application/json; charset=UTF-8
+
+  )]}'
+  {
+    "name": "Code-Review",
+    "status": "SATISFIED",
+    "submittability_expression_result": {
+      "expression": "label:Code-Review=+2",
+      "fulfilled": true,
+      "passingAtoms": [
+        "label:Code-Review=+2"
+      ]
+    },
+    "is_legacy": false
+  }
+----
+
+GERRIT
+------
+Part of link:index.html[Gerrit Code Review]
+
+SEARCHBOX
+---------
diff --git a/Documentation/config-themes.txt b/Documentation/config-themes.txt
index a83c747..73cfc55 100644
--- a/Documentation/config-themes.txt
+++ b/Documentation/config-themes.txt
@@ -4,11 +4,12 @@
 the browser, allowing organizations to alter the look and
 feel of the application to fit with their general scheme.
 
-== HTML Header/Footer and CSS
+== HTML Header/Footer and CSS for login screens
 
-The HTML header, footer and CSS may be customized for login
-screens (LDAP, OAuth, OpenId) and the internally managed
-Gitweb servlet.
+The HTML header, footer, and CSS may be customized for login screens (LDAP,
+OAuth, OpenId) and the internally managed Gitweb servlet. See
+link:pg-plugin-dev.html[JavaScript Plugin Development and API] for documentation
+on modifying styles for the rest of Gerrit (not login screens).
 
 At startup Gerrit reads the following files (if they exist) and
 uses them to customize the HTML page it sends to clients:
diff --git a/Documentation/dev-bazel.txt b/Documentation/dev-bazel.txt
index e6a118e..d1a5bcf 100644
--- a/Documentation/dev-bazel.txt
+++ b/Documentation/dev-bazel.txt
@@ -18,7 +18,7 @@
 To build Gerrit from source, you need:
 
 * A Linux or macOS system (Windows is not supported at this time)
-* A JDK for Java 8|11|...
+* A JDK for Java 11 or Java 17
 * Python 3
 * link:https://github.com/nodesource/distributions/blob/master/README.md[Node.js (including npm),role=external,window=_blank]
 * Bower (`npm install -g bower`)
@@ -48,16 +48,6 @@
 
 `java -version`
 
-[[java-8]]
-==== Java 8 support (deprecated)
-
-Java 8 is a legacy Java release and support for Java 8 will be discontinued
-in future gerrit releases. To build Gerrit with Java 8 language level, run:
-
-```
-  $ bazel build :release
-```
-
 [[java-11]]
 ==== Java 11 support
 
@@ -67,53 +57,21 @@
   $ bazel build --java_toolchain=//tools:error_prone_warnings_toolchain_java11 :release
 ```
 
-[[java-13]]
-==== Java 13 support
+[[java-17]]
+==== Java 17 support
 
-Java 13 (and newer) is supported through vanilla java toolchain
-link:https://docs.bazel.build/versions/master/toolchains.html[Bazel option,role=external,window=_blank].
-To build Gerrit with Java 13 and newer, specify vanilla java toolchain and
-provide the path to JDK home:
+Java 17 is supported. To build Gerrit with Java 17, run:
 
 ```
-  $ bazel build \
-    --define=ABSOLUTE_JAVABASE=<path-to-java-13> \
-    --javabase=@bazel_tools//tools/jdk:absolute_javabase \
-    --host_javabase=@bazel_tools//tools/jdk:absolute_javabase \
-    --host_java_toolchain=@bazel_tools//tools/jdk:toolchain_vanilla \
-    --java_toolchain=@bazel_tools//tools/jdk:toolchain_vanilla \
-    :release
+  $ bazel build --config=java17 :release
 ```
 
-To run the tests, `--javabase` option must be passed as well, because
-bazel test runs the test using the target javabase:
+To run the tests with Java 17, run:
 
 ```
-  $ bazel test \
-    --define=ABSOLUTE_JAVABASE=<path-to-java-13> \
-    --javabase=@bazel_tools//tools/jdk:absolute_javabase \
-    --host_javabase=@bazel_tools//tools/jdk:absolute_javabase \
-    --host_java_toolchain=@bazel_tools//tools/jdk:toolchain_vanilla \
-    --java_toolchain=@bazel_tools//tools/jdk:toolchain_vanilla \
-    //...
+  $ bazel test --config=java17 //...
 ```
 
-To avoid passing all those options on every Bazel build invocation,
-they could be added to ~/.bazelrc resource file:
-
-```
-$ cat << EOF > ~/.bazelrc
-build --define=ABSOLUTE_JAVABASE=<path-to-java-13>
-build --javabase=@bazel_tools//tools/jdk:absolute_javabase
-build --host_javabase=@bazel_tools//tools/jdk:absolute_javabase
-build --host_java_toolchain=@bazel_tools//tools/jdk:toolchain_vanilla
-build --java_toolchain=@bazel_tools//tools/jdk:toolchain_vanilla
-EOF
-```
-
-Now, invoking Bazel with just `bazel build :release` would include
-all those options.
-
 === Node.js and npm packages
 See link:https://gerrit.googlesource.com/gerrit/+/master/polygerrit-ui/README.md#installing-node_js-and-npm-packages[Installing Node.js and npm packages,role=external,window=_blank].
 
@@ -324,18 +282,6 @@
   bazel test //javatests/com/google/gerrit/acceptance/rest/account:rest_account
 ----
 
-To run SSH tests using JSch ssh client:
-
-----
-  bazel test --test_env=SSH_CLIENT_IMPLEMENTATION=JSCH //...
-----
-
-To run SSH tests using Apache MINA ssh client:
-
-----
-  bazel test --test_env=SSH_CLIENT_IMPLEMENTATION=APACHE //...
-----
-
 To run only tests that do not use SSH:
 
 ----
diff --git a/Documentation/dev-design-docs.txt b/Documentation/dev-design-docs.txt
index 6dc6f5f..efba520 100644
--- a/Documentation/dev-design-docs.txt
+++ b/Documentation/dev-design-docs.txt
@@ -13,7 +13,7 @@
 * Use-Cases:
   The interactions between a user and a system to attain particular
   goals.
-* Acceptance Criteria
+* Acceptance Criteria:
   Conditions that must be satisfied to consider the feature as done.
 * Background:
   Stuff one needs to know to understand the use-cases (e.g. motivating
diff --git a/Documentation/dev-e2e-tests.txt b/Documentation/dev-e2e-tests.txt
index c50a293..8e5463d 100644
--- a/Documentation/dev-e2e-tests.txt
+++ b/Documentation/dev-e2e-tests.txt
@@ -102,8 +102,7 @@
 === SSH keys
 
 If you are running SSH commands, the private keys of the users used for testing need to go in
-`/tmp/ssh-keys`. The keys need to be generated this way (JSch won't validate them
-link:https://stackoverflow.com/questions/53134212/invalid-privatekey-when-using-jsch[otherwise,role=external,window=_blank]):
+`/tmp/ssh-keys`. The keys need to be generated this way and won't be validated.
 
 ----
 mkdir /tmp/ssh-keys
@@ -174,6 +173,9 @@
 * `-Dcom.google.gerrit.scenarios.ssh_port=29418`
 * `-Dcom.google.gerrit.scenarios.http_port=8080`
 * `-Dcom.google.gerrit.scenarios.http_scheme=http`
+* `-Dcom.google.gerrit.scenarios.username=admin`
+* `-Dcom.google.gerrit.scenarios.replica_hostname=localhost`
+* `-Dcom.google.gerrit.scenarios.project_prefix=`
 
 Above, the properties can be set with values matching specific deployment topologies under test.
 The name of the property corresponds to the uppercase keyword found in the json file. For example,
@@ -195,6 +197,13 @@
 That whole replication time depends on the system under test. Therefore, this property here should
 be set to a value high enough, so that the test checks for a done replication at the right time.
 
+==== Context path
+
+The `context_path` property allows test scenarios to send Gerrit REST requests to Gerrit instances
+that use a context path in the URL. Its default is no context path and can be set using another value:
+
+* `-Dcom.google.gerrit.scenarios.context_path=/context`
+
 ==== Automatic properties
 
 The link:#_input_file[example keywords,role=external,window=_blank] also include `_PROJECT`,
diff --git a/Documentation/dev-eclipse.txt b/Documentation/dev-eclipse.txt
index e18d7b0..dce5eb0 100644
--- a/Documentation/dev-eclipse.txt
+++ b/Documentation/dev-eclipse.txt
@@ -31,9 +31,6 @@
 ----
 
 First, generate the Eclipse project by running the `tools/eclipse/project.py` script.
-If running Eclipse on Java 8, add the extra parameter
-`-e='--java_toolchain=//tools:error_prone_warnings_toolchain'`
-for generating a compatible project.
 
 Then, in Eclipse, choose 'Import existing project' and select the `gerrit` project
 from the current working directory.
diff --git a/Documentation/dev-plugins-lifecycle.txt b/Documentation/dev-plugins-lifecycle.txt
index d5bd791..2f5ffb7 100644
--- a/Documentation/dev-plugins-lifecycle.txt
+++ b/Documentation/dev-plugins-lifecycle.txt
@@ -15,14 +15,14 @@
 The idea of creating a new plugin is posted and discussed on the
 link:https://groups.google.com/d/forum/repo-discuss[repo-discuss,role=external,window=_blank] mailing list.
 +
-Also see section link#ideation_discussion[Ideation and discussion] below.
+Also see section <<ideation_discussion>> below.
 
 - Prototyping (optional):
 +
 The author of the plugin creates a working prototype on a public repository
 accessible to the community.
 +
-Also see section link#plugin_prototyping[Plugin Prototyping] below.
+Also see section <<plugin_prototyping>> below.
 
 - Proposal and Hosting:
 +
@@ -37,7 +37,7 @@
 plugins path on link:https://gerrit-review.googlesource.com[the Gerrit project
 site,role=external,window=_blank].
 +
-Also see section link#plugin_proposal[Plugin Proposal] below.
+Also see section <<plugin_proposal>> below.
 
 - Build:
 +
@@ -46,14 +46,14 @@
 link:https://gerrit-ci.gerritforge.com[the GerritForge CI,role=external,window=_blank] that build the
 plugin for each Gerrit version that it supports.
 +
-Also see section link#build[Build] below.
+Also see section <<build>> below.
 
 - Development and Contribution:
 +
 The author develops a production-ready code base of the plugin, with
 contributions, reviews, and help from the Gerrit community.
 +
-Also see section link#development_contribution[Development and contribution]
+Also see section <<development_contribution>>
 below.
 
 - Release:
@@ -62,7 +62,7 @@
 on the link:https://groups.google.com/d/forum/repo-discuss[repo-discuss,role=external,window=_blank]
 mailing list.
 +
-Also see section link#plugin_release[Plugin release] below.
+Also see section <<plugin_release>> below.
 
 - Maintenance:
 +
@@ -75,7 +75,7 @@
 The author declares that the plugin is not maintained anymore or is deprecated
 and should not be used anymore.
 +
-Also see section link#plugin_deprecation[Plugin deprecation] below.
+Also see section <<plugin_deprecation>> below.
 
 [[ideation_discussion]]
 == Ideation and Discussion
diff --git a/Documentation/dev-plugins.txt b/Documentation/dev-plugins.txt
index eb94ef7..ca72f8b 100644
--- a/Documentation/dev-plugins.txt
+++ b/Documentation/dev-plugins.txt
@@ -2,8 +2,9 @@
 = Gerrit Code Review - Plugin Development
 
 The Gerrit server functionality can be extended by installing plugins.
-This page describes how plugins for Gerrit can be developed and hosted
-on gerrit-review.googlesource.com.
+This page describes how plugins for Gerrit can be developed. See the overall
+link:dev-plugins-lifecycle.html[Plugin Lifecycle] document for how plugins can
+be hosted on gerrit-review.googlesource.com.
 
 For JavaScript plugin development, consult with
 link:pg-plugin-dev.html[JavaScript Plugin Development] guide.
@@ -207,6 +208,28 @@
 The canonical web URL may be injected into any .jar plugin regardless of
 whether or not the plugin provides an HTTP servlet.
 
+[[plugin_resources]]
+=== Plugin resources
+
+Plugins are able to access their own resources without having to go through
+the implementation details on how they are packaged or deployed to Gerrit.
+
+The following example shows a MyClass in a plugin that is able to access the
+last modified time of the "myresource" loaded.
+
+[source,java]
+----
+public class MyClass {
+
+  @Inject
+  public MyClass(Plugin plugin) {
+    long myresourceTime = plugin.getContentScanner().getEntry("myresource").getTime();
+  }
+
+  [...]
+}
+----
+
 [[reload_method]]
 === Reload Method
 
@@ -415,6 +438,17 @@
 +
 Publication of usage data
 
+* `com.google.gerrit.extensions.events.GitReferenceUpdatedListener`:
++
+A git reference was updated. A separate event for every ref updated in
+a BatchRefUpdate will be fired.
+
+* `com.google.gerrit.extensions.events.GitBatchRefUpdateListener`:
++
+One or more git references were updated. Alternative to GitReferenceUpdatedListener.
+A single event will inform about all refs updated by a BatchRefUpdate. Will also be
+fired, if only a single ref was updated.
+
 * `com.google.gerrit.extensions.events.GarbageCollectorListener`:
 +
 Garbage collection ran on a project
@@ -2770,6 +2804,23 @@
 prevent callers using ETags from potentially seeing outdated submittability
 information.
 
+`SubmitRule` interface will soon deprecated. Instead, a global `SubmitRequirement`
+can be bound by plugin.
+
+[source, java]
+----
+import com.google.gerrit.extensions.annotations.Exports;
+import com.google.inject.AbstractModule;
+
+public class MyPluginModule extends AbstractModule {
+  @Override
+  protected void configure() {
+    bind(SubmitRequirement.class).annotatedWith(Exports.named("myPlugin"))
+        .toInstance(myPluginSubmitRequirement);
+  }
+}
+----
+
 [[change-etag-computation]]
 == Change ETag Computation
 
diff --git a/Documentation/dev-processes.txt b/Documentation/dev-processes.txt
index e43e021..3bd88f5 100644
--- a/Documentation/dev-processes.txt
+++ b/Documentation/dev-processes.txt
@@ -366,7 +366,10 @@
 * If the library is used within Google, the version of the library must be compatible with the
   version that is used at Google.
 
-Only maintainers from Google can vote on the `Library-Compliance` label.
+Only maintainers from Google can vote on the `Library-Compliance` label. The
+Gerrit team at Google uses this
+link:https://gerrit-review.googlesource.com/q/label:%2522Library-Compliance%253Dneed%2522+-ownerin:google-gerrit-team+status:open+project:gerrit+-age:4week+-is:wip+-is:private+label:Code-Review%252B2[change query]
+to find changes that require a `Library-Compliance` approval.
 
 Gerrit's library dependencies should only be upgraded if the new version contains
 something we need in Gerrit. This includes new features, API changes as well as bug
@@ -378,6 +381,12 @@
 that they are vetted long enough before they go into a release and we can be sure
 that the update doesn't introduce a regression.
 
+[[escalation-channel-to-google]]
+== Escalation channel to Google
+
+If anything urgent is blocking that requires the attention of a Googler you may
+escalate this by writing an email to Han-Wen Nienhuys: hanwen@google.com
+
 [[deprecating-features]]
 == Deprecating features
 
diff --git a/Documentation/index.txt b/Documentation/index.txt
index 782a6a9..9afd6e3 100644
--- a/Documentation/index.txt
+++ b/Documentation/index.txt
@@ -43,6 +43,7 @@
 == Project Management
 . link:project-configuration.html[Project Configuration]
 .. link:config-labels.html[Review Labels]
+.. link:config-submit-requirements.html[Submit Requirements]
 .. link:config-project-config.html[Project Configuration File Format]
 . link:access-control.html[Access Controls]
 . Multi-project management
diff --git a/Documentation/intro-gerrit-walkthrough.txt b/Documentation/intro-gerrit-walkthrough.txt
index 6565ba4..ff37ffc 100644
--- a/Documentation/intro-gerrit-walkthrough.txt
+++ b/Documentation/intro-gerrit-walkthrough.txt
@@ -161,8 +161,8 @@
 * `+2 Looks good to me, approved`
 * `+1 Looks good to me, but someone else must approve`
 * `0 No score`
-* `-1 I would prefer that you didn't submit this`
-* `-2 Do not submit`
+* `-1 I would prefer this is not submitted as is`
+* `-2 This shall not be submitted`
 
 In addition, a change must have at least one `+2` vote and no `-2` votes before
 it can be submitted. These numerical values do not accumulate. Two
diff --git a/Documentation/intro-user.txt b/Documentation/intro-user.txt
index 1f0dfd0..c3abedb 100644
--- a/Documentation/intro-user.txt
+++ b/Documentation/intro-user.txt
@@ -662,6 +662,10 @@
 * If you have a series of private changes and share one with reviewers,
   the reviewers can also see the commits of the predecessor private
   changes through the commit parent relationship.
+* Users who would have permission to access the change except for its
+  private status and knowledge of its commit ID (e.g. through CI logs
+  or build artifacts containing build numbers) can fetch the code
+  using the commit ID.
 
 [[ignore]]
 == Ignoring Or Marking Changes As 'Reviewed'
@@ -807,16 +811,21 @@
 +
 This setting controls the email notifications.
 +
-** `Enabled`:
-+
-Email notifications are enabled.
-+
 ** [[cc-me]]`Every comment`:
 +
 Email notifications are enabled and you get notified by email as CC
 on comments that you write yourself.
 +
-** `Disabled`:
+** `Only comments left by others`
++
+Email notifications are enabled for all activities excluding comments or
+reviews authored by you.
++
+** `Only when I am in the attention set`
++
+Email notifications are only sent if the recipient is in the attention set.
++
+** `None`:
 +
 Email notifications are disabled.
 
diff --git a/Documentation/js_licenses.txt b/Documentation/js_licenses.txt
index ab79c8f..5b7e073 100644
--- a/Documentation/js_licenses.txt
+++ b/Documentation/js_licenses.txt
@@ -1120,6 +1120,126 @@
 ----
 
 
+[[highlight_js]]
+highlight.js
+
+* highlight.js
+
+[[highlight_js_license]]
+----
+BSD 3-Clause License
+
+Copyright (c) 2006, Ivan Sagalaev.
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+* Redistributions of source code must retain the above copyright notice, this
+  list of conditions and the following disclaimer.
+
+* Redistributions in binary form must reproduce the above copyright notice,
+  this list of conditions and the following disclaimer in the documentation
+  and/or other materials provided with the distribution.
+
+* Neither the name of the copyright holder nor the names of its
+  contributors may be used to endorse or promote products derived from
+  this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+----
+
+
+[[highlightjs-closure-templates]]
+highlightjs-closure-templates
+
+* highlightjs-closure-templates
+
+[[highlightjs-closure-templates_license]]
+----
+BSD 3-Clause License
+
+Copyright (c) 2006, Ivan Sagalaev.
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+* Redistributions of source code must retain the above copyright notice, this
+  list of conditions and the following disclaimer.
+
+* Redistributions in binary form must reproduce the above copyright notice,
+  this list of conditions and the following disclaimer in the documentation
+  and/or other materials provided with the distribution.
+
+* Neither the name of the copyright holder nor the names of its
+  contributors may be used to endorse or promote products derived from
+  this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+----
+
+
+[[highlightjs-structured-text]]
+highlightjs-structured-text
+
+* highlightjs-structured-text
+
+[[highlightjs-structured-text_license]]
+----
+BSD 3-Clause License

+

+Copyright (c) 2006, Ivan Sagalaev

+All rights reserved.

+

+Redistribution and use in source and binary forms, with or without

+modification, are permitted provided that the following conditions are met:

+

+1. Redistributions of source code must retain the above copyright notice, this

+   list of conditions and the following disclaimer.

+

+2. Redistributions in binary form must reproduce the above copyright notice,

+   this list of conditions and the following disclaimer in the documentation

+   and/or other materials provided with the distribution.

+

+3. Neither the name of the copyright holder nor the names of its

+   contributors may be used to endorse or promote products derived from

+   this software without specific prior written permission.

+

+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"

+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE

+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE

+FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

+DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR

+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER

+CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,

+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+----
+
+
 [[immer]]
 immer
 
diff --git a/Documentation/licenses.txt b/Documentation/licenses.txt
index 735553d..e5966de 100644
--- a/Documentation/licenses.txt
+++ b/Documentation/licenses.txt
@@ -32,7 +32,7 @@
 Gerrit includes an SSH daemon (Apache SSHD), to support authenticated
 uploads of changes directly from `git push` command line clients.
 
-Gerrit includes an SSH client (JSch), to support authenticated
+Gerrit includes an SSH client (Apache SSHD), to support authenticated
 replication of changes to remote systems, such as for automatic
 updates of mirror servers, or realtime backups.
 
@@ -48,10 +48,10 @@
 * commons:codec
 * commons:compress
 * commons:dbcp
-* commons:lang
 * commons:lang3
 * commons:net
 * commons:pool
+* commons:text
 * commons:validator
 * dropwizard:dropwizard-core
 * errorprone:annotations
@@ -2331,7 +2331,6 @@
 * jgit-archive
 * jgit-servlet
 * jgit-ssh-apache
-* jgit-ssh-jsch
 
 [[jgit_license]]
 ----
@@ -2376,43 +2375,6 @@
 ----
 
 
-[[jsch]]
-jsch
-
-* jsch
-
-[[jsch_license]]
-----
-Copyright (c) 2002-2012 Atsuhiko Yamanaka, JCraft,Inc.
-All rights reserved.
-
-Redistribution and use in source and binary forms, with or without
-modification, are permitted provided that the following conditions are met:
-
-  1. Redistributions of source code must retain the above copyright notice,
-     this list of conditions and the following disclaimer.
-
-  2. Redistributions in binary form must reproduce the above copyright
-     notice, this list of conditions and the following disclaimer in
-     the documentation and/or other materials provided with the distribution.
-
-  3. The names of the authors may not be used to endorse or promote products
-     derived from this software without specific prior written permission.
-
-THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
-INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
-FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL JCRAFT,
-INC. OR ANY CONTRIBUTORS TO THIS SOFTWARE BE LIABLE FOR ANY DIRECT, INDIRECT,
-INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
-OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
-LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
-NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
-EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-----
-
-
 [[jsoup]]
 jsoup
 
@@ -4061,6 +4023,126 @@
 ----
 
 
+[[highlight_js]]
+highlight.js
+
+* highlight.js
+
+[[highlight_js_license]]
+----
+BSD 3-Clause License
+
+Copyright (c) 2006, Ivan Sagalaev.
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+* Redistributions of source code must retain the above copyright notice, this
+  list of conditions and the following disclaimer.
+
+* Redistributions in binary form must reproduce the above copyright notice,
+  this list of conditions and the following disclaimer in the documentation
+  and/or other materials provided with the distribution.
+
+* Neither the name of the copyright holder nor the names of its
+  contributors may be used to endorse or promote products derived from
+  this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+----
+
+
+[[highlightjs-closure-templates]]
+highlightjs-closure-templates
+
+* highlightjs-closure-templates
+
+[[highlightjs-closure-templates_license]]
+----
+BSD 3-Clause License
+
+Copyright (c) 2006, Ivan Sagalaev.
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+* Redistributions of source code must retain the above copyright notice, this
+  list of conditions and the following disclaimer.
+
+* Redistributions in binary form must reproduce the above copyright notice,
+  this list of conditions and the following disclaimer in the documentation
+  and/or other materials provided with the distribution.
+
+* Neither the name of the copyright holder nor the names of its
+  contributors may be used to endorse or promote products derived from
+  this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+----
+
+
+[[highlightjs-structured-text]]
+highlightjs-structured-text
+
+* highlightjs-structured-text
+
+[[highlightjs-structured-text_license]]
+----
+BSD 3-Clause License

+

+Copyright (c) 2006, Ivan Sagalaev

+All rights reserved.

+

+Redistribution and use in source and binary forms, with or without

+modification, are permitted provided that the following conditions are met:

+

+1. Redistributions of source code must retain the above copyright notice, this

+   list of conditions and the following disclaimer.

+

+2. Redistributions in binary form must reproduce the above copyright notice,

+   this list of conditions and the following disclaimer in the documentation

+   and/or other materials provided with the distribution.

+

+3. Neither the name of the copyright holder nor the names of its

+   contributors may be used to endorse or promote products derived from

+   this software without specific prior written permission.

+

+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"

+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE

+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE

+FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

+DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR

+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER

+CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,

+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+----
+
+
 [[immer]]
 immer
 
diff --git a/Documentation/metrics.txt b/Documentation/metrics.txt
index 49ac84c..9df4b04 100644
--- a/Documentation/metrics.txt
+++ b/Documentation/metrics.txt
@@ -116,7 +116,7 @@
 * `receivecommits/ps_revision_missing`: errors due to patch set revision missing
 * `receivecommits/push_count`: number of pushes
 ** `kind`:
-   The push kind (direct vs. magic).
+   The push kind (magic, direct or direct_submit).
 ** `project`:
    The name of the project for which the push is done.
 ** `type`:
diff --git a/Documentation/pg-plugin-checks-api.txt b/Documentation/pg-plugin-checks-api.txt
index 4e93da1..8786cc4 100644
--- a/Documentation/pg-plugin-checks-api.txt
+++ b/Documentation/pg-plugin-checks-api.txt
@@ -24,8 +24,8 @@
 Here are some examples of open source plugins that make use of the Checks API:
 
 * link:https://gerrit.googlesource.com/plugins/checks/+/master/gr-checks/plugin.js[Gerrit Checks Plugin]
-* link:https://chromium.googlesource.com/infra/gerrit-plugins/buildbucket/+/master/src/main/resources/static/buildbucket.js[Chromium Buildbucket Plugin]
-* link:https://chromium.googlesource.com/infra/gerrit-plugins/code-coverage/+/master/src/main/resources/static/chromium-coverage.js[Chromium Coverage Plugin]
+* link:https://chromium.googlesource.com/infra/gerrit-plugins/buildbucket/+/main/web/plugin.ts[Chromium Buildbucket Plugin]
+* link:https://chromium.googlesource.com/infra/gerrit-plugins/code-coverage/+/main/web/plugin.ts[Chromium Coverage Plugin]
 
 [[register]]
 == register
diff --git a/Documentation/pg-plugin-dev.txt b/Documentation/pg-plugin-dev.txt
index dc65da6..381c3e1 100644
--- a/Documentation/pg-plugin-dev.txt
+++ b/Documentation/pg-plugin-dev.txt
@@ -30,10 +30,6 @@
 });
 ```
 
-You can find more elaborate examples in the
-link:https://gerrit.googlesource.com/gerrit/+/master/polygerrit-ui/app/samples/[polygerrit-ui/app/samples/]
-directory of the source tree.
-
 == TypeScript API ==
 
 Gerrit provides a TypeScript plugin API.
@@ -122,32 +118,26 @@
 [[low-level-style]]
 === Styling DOM Elements
 
-A plugin may provide Polymer's
-https://polymer-library.polymer-project.org/3.0/docs/devguide/style-shadow-dom[style
-modules,role=external,window=_blank] to style individual endpoints using
-`plugin.registerStyleModule(endpointName, moduleName)`. A style must be defined
-as a standalone `<dom-module>` defined in the same .js file.
+Gerrit only offers customized CSS styling by setting
+link:https://developer.mozilla.org/en-US/docs/Web/CSS/Using_CSS_[custom_properties]
+(aka css variables).
 
-See
-link:https://gerrit.googlesource.com/gerrit/+/master/polygerrit-ui/app/samples/theme-plugin.js[samples/theme-plugin.js]
-for an example.
+See link:https://gerrit.googlesource.com/gerrit/+/master/polygerrit-ui/app/styles/themes/[app-theme.ts]
+for the list of available variables.
+
+Just add code like this to your JavaScript plugin:
 
 ``` js
-const styleElement = document.createElement('dom-module');
-styleElement.innerHTML =
- `<template>
-    <style>
-    html {
-      --primary-text-color: red;
-    }
-   </style>
- </template>`;
-
-styleElement.register('some-style-module');
-
-Gerrit.install(plugin => {
-  plugin.registerStyleModule('change-metadata', 'some-style-module');
-});
+    const styleEl = document.createElement('style');
+    styleEl.innerHTML = `
+        html {
+          --header-background-color: #c3d9ff;
+        }
+        html.darkTheme {
+          --header-background-color: #c3d9ff90;
+        }
+    `;
+    document.head.appendChild(styleEl);
 ```
 
 [[high-level-api-concepts]]
@@ -173,10 +163,6 @@
 binding,role=external,window=_blank] for plugins that don't use Polymer. Can be used to bind element
 attribute changes to callbacks.
 
-See
-link:https://gerrit.googlesource.com/gerrit/+/master/polygerrit-ui/app/samples/bind-parameters.js[samples/bind-parameters.js]
-for an example.
-
 === hook
 `plugin.hook(endpointName, opt_options)`
 
@@ -196,7 +182,8 @@
 === registerStyleModule
 `plugin.registerStyleModule(endpointName, moduleName)`
 
-See link:#low-level-style[above].
+This API is deprecated and will be removed either in version 3.6 or 3.7,
+see link:#low-level-style[above] for an alternative.
 
 === on
 Register a JavaScript callback to be invoked when events occur within
diff --git a/Documentation/pg-plugin-endpoints.txt b/Documentation/pg-plugin-endpoints.txt
index c16d0d4..f2a72f1 100644
--- a/Documentation/pg-plugin-endpoints.txt
+++ b/Documentation/pg-plugin-endpoints.txt
@@ -228,3 +228,13 @@
 +
 current revision displayed, an instance of
 link:rest-api-changes.html#revision-info[RevisionInfo]
+
+=== account-status-icon
+The `account-status-icon` extension point adds an icon to all account chips and
+labels.
+
+In addition to default parameters, the following are available:
+
+* `accountId`
++
+the Id of the account that the status icon should correspond to.
\ No newline at end of file
diff --git a/Documentation/pgm-daemon.txt b/Documentation/pgm-daemon.txt
index cf6560b..586f685 100644
--- a/Documentation/pgm-daemon.txt
+++ b/Documentation/pgm-daemon.txt
@@ -61,7 +61,7 @@
 	Run init before starting the daemon. This will create a new site or
 	upgrade an existing site.
 
---s::
+-s::
 	Start link:dev-inspector.html[Gerrit Inspector] on the console, a
 	built-in interactive inspection environment to assist debugging and
 	troubleshooting of Gerrit code.
diff --git a/Documentation/rest-api-access.txt b/Documentation/rest-api-access.txt
index 45a39d8..991f36c 100644
--- a/Documentation/rest-api-access.txt
+++ b/Documentation/rest-api-access.txt
@@ -388,7 +388,7 @@
 |`revision`           ||
 The revision of the `refs/meta/config` branch from which the access
 rights were loaded.
-|`inherits_from`      |not set for the `All-Project` project|
+|`inherits_from`      |not set for the `All-Projects` project|
 The parent project from which permissions are inherited as a
 link:rest-api-projects.html#project-info[ProjectInfo] entity.
 |`local`              ||
diff --git a/Documentation/rest-api-changes.txt b/Documentation/rest-api-changes.txt
index 5df78cc..f270ac5 100644
--- a/Documentation/rest-api-changes.txt
+++ b/Documentation/rest-api-changes.txt
@@ -224,19 +224,18 @@
 
 [[labels]]
 --
-* `LABELS`: a summary of each label required for submit, and
-  approvers that have granted (or rejected) with that label
-  as well as all reviewers by state, and reviewers that may
-  be removed by the current user.
+* `LABELS`: Includes the `labels` field which contains all information about
+labels and approvers that have granted (or rejected) that label. Does not
+include the `permitted_voting_range` attribute with the list of
+link:#approval-info[ApprovalInfo] of the `all` attribute.
 --
 
 [[detailed-labels]]
 --
-* `DETAILED_LABELS`: detailed label information, including numeric
-  values of all existing approvals, recognized label values, values
-  permitted to be set by any reviewer and the change owner, all
-  reviewers by state, and reviewers that may be removed by the
-  current user.
+* `DETAILED_LABELS`: Includes the `labels` field which contains all information
+about labels and approvers that have granted (or rejected) that label, including
+the `permitted_voting_range` attribute with the list of
+link:#approval-info[ApprovalInfo] of the `all` attribute.
 --
 
 [[submit-requirements]]
@@ -795,8 +794,8 @@
           }
         ]
         "values": {
-          "-2": "This shall not be merged",
-          "-1": "I would prefer this is not merged as is",
+          "-2": "This shall not be submitted",
+          "-1": "I would prefer this is not submitted as is",
           " 0": "No score",
           "+1": "Looks good to me, but someone else must approve",
           "+2": "Looks good to me, approved"
@@ -1857,7 +1856,8 @@
 
 * The given change.
 * If link:config-gerrit.html#change.submitWholeTopic[`change.submitWholeTopic`]
-  is enabled, include all open changes with the same topic.
+  is enabled OR if the `o=TOPIC_CLOSURE` query parameter is passed, include all
+  open changes with the same topic.
 * For each change whose submit type is not CHERRY_PICK, include unmerged
   ancestors targeting the same branch.
 
@@ -1884,7 +1884,7 @@
 
 Standard link:#query-options[formatting options] can be specified
 with the `o` parameter, as well as the `submitted_together` specific
-option `NON_VISIBLE_CHANGES`.
+options `NON_VISIBLE_CHANGES` and `TOPIC_CLOSURE`.
 
 .Response
 ----
@@ -1925,8 +1925,8 @@
             }
           ],
           "values": {
-            "-2": "This shall not be merged",
-            "-1": "I would prefer this is not merged as is",
+            "-2": "This shall not be submitted",
+            "-1": "I would prefer this is not submitted as is",
             " 0": "No score",
             "+1": "Looks good to me, but someone else must approve",
             "+2": "Looks good to me, approved"
@@ -2022,8 +2022,8 @@
             }
           ],
           "values": {
-            "-2": "This shall not be merged",
-            "-1": "I would prefer this is not merged as is",
+            "-2": "This shall not be submitted",
+            "-1": "I would prefer this is not submitted as is",
             " 0": "No score",
             "+1": "Looks good to me, but someone else must approve",
             "+2": "Looks good to me, approved"
@@ -3973,8 +3973,8 @@
           }
         ]
         "values": {
-          "-2": "This shall not be merged",
-          "-1": "I would prefer this is not merged as is",
+          "-2": "This shall not be submitted",
+          "-1": "I would prefer this is not submitted as is",
           " 0": "No score",
           "+1": "Looks good to me, but someone else must approve",
           "+2": "Looks good to me, approved"
@@ -4581,60 +4581,6 @@
 If the `path` parameter is set, the returned content is a diff of the single
 file that the path refers to.
 
-[[submit-preview]]
-=== Submit Preview
---
-'GET /changes/link:#change-id[\{change-id\}]/revisions/link:#revision-id[\{revision-id\}]/preview_submit'
---
-Gets a file containing thin bundles of all modified projects if this
-change was submitted. The bundles are named `${ProjectName}.git`.
-Each thin bundle contains enough to construct the state in which a project would
-be in if this change were submitted. The base of the thin bundles are the
-current target branches, so to make use of this call in a non-racy way, first
-get the bundles and then fetch all projects contained in the bundle.
-(This assumes no non-fastforward pushes).
-
-You need to give a parameter '?format=zip' or '?format=tar' to specify the
-format for the outer container. It is always possible to use tgz, even if
-tgz is not in the list of allowed archive formats.
-
-To make good use of this call, you would roughly need code as found at:
-----
- $ curl -Lo preview_submit_test.sh http://review.example.com:8080/tools/scripts/preview_submit_test.sh
-----
-.Request
-----
-  GET /changes/myProject~master~I8473b95934b5732ac55d26311a706c9c2bde9940/revisions/current/preview_submit?zip HTTP/1.0
-----
-
-.Response
-----
-  HTTP/1.1 200 OK
-  Date: Tue, 13 Sep 2016 19:13:46 GMT
-  Content-Disposition: attachment; filename="submit-preview-147.zip"
-  X-Content-Type-Options: nosniff
-  Cache-Control: no-cache, no-store, max-age=0, must-revalidate
-  Pragma: no-cache
-  Expires: Mon, 01 Jan 1990 00:00:00 GMT
-  Content-Type: application/x-zip
-  Transfer-Encoding: chunked
-
-  [binary stuff]
-----
-
-In case of an error, the response is not a zip file but a regular json response,
-containing only the error message:
-
-.Response
-----
-  HTTP/1.1 200 OK
-  Content-Disposition: attachment
-  Content-Type: application/json; charset=UTF-8
-
-  )]}'
-  "Anonymous users cannot submit"
-----
-
 [[get-mergeable]]
 === Get Mergeable
 --
@@ -5084,6 +5030,9 @@
 with a new message, which contains the name of the user who deletes
 the comment and the reason why it's deleted.
 
+This endpoint also marks the comment as resolved since deleted comments are not
+actionable.
+
 Note that only users with the
 link:access-control.html#capability_administrateServer[Administrate Server]
 global capability are permitted to delete a comment.
@@ -5224,8 +5173,8 @@
   }
 ----
 
-[[get-ported-comments]]
-=== Get Ported Comments
+[[list-ported-comments]]
+=== List Ported Comments
 --
 'GET /changes/link:#change-id[\{change-id\}]/revisions/link:#revision-id[\{revision-id\}]/ported_comments'
 --
@@ -5308,24 +5257,24 @@
   }
 ----
 
-[[get-ported-drafts]]
-=== Get Ported Drafts
+[[list-ported-drafts]]
+=== List Ported Drafts
 --
 'GET /changes/link:#change-id[\{change-id\}]/revisions/link:#revision-id[\{revision-id\}]/ported_drafts'
 --
 
 Ports draft comments of other revisions to the requested revision.
 
-This endpoint behaves similarly to the link:#get-ported-comments[Get Ported Comments] endpoint.
+This endpoint behaves similarly to the link:#list-ported-comments[List Ported Comments] endpoint.
 With this endpoint, only draft comments of the calling user are ported, though. If a draft comment
 is a reply to a published comment, only the ported draft comment is returned.
 
 Depending on the filtering rules, it's possible that this endpoint returns a draft comment which is
 a reply to a comment thread which is not returned by the
-link:#get-ported-comments[Get Ported Comments] endpoint. That's intended behavior. Callers must be
+link:#list-ported-comments[List Ported Comments] endpoint. That's intended behavior. Callers must be
 able to handle this situation. The same holds for drafts which are a reply to a robot comment.
 
-Different than the link:#get-ported-comments[Get Ported Comments] endpoint, the `author` of the
+Different than the link:#list-ported-comments[List Ported Comments] endpoint, the `author` of the
 returned comments is not filled for this endpoint as only comments of the calling user are returned.
 
 This endpoint requires authentication.
@@ -6529,7 +6478,14 @@
 |`topic`              |optional|The topic to which this change belongs.
 |`attention_set`      |optional|
 The map that maps link:rest-api-accounts.html#account-id[account IDs]
-to link:#attention-set-info[AttentionSetInfo] of that account.
+to link:#attention-set-info[AttentionSetInfo] of that account. Those are all
+accounts that are currently in the attention set.
+|`removed_from_attention_set`      |optional|
+The map that maps link:rest-api-accounts.html#account-id[account IDs]
+to link:#attention-set-info[AttentionSetInfo] of that account. Those are all
+accounts that were in the attention set but were removed. The
+link:#attention-set-info[AttentionSetInfo] is the latest and most recent removal
+ of the account from the attention set.
 |`assignee`           |optional|
 The assignee of the change as an link:rest-api-accounts.html#account-info[
 AccountInfo] entity.
@@ -6807,28 +6763,28 @@
 
 [options="header",cols="1,^1,5"]
 |===========================
-|Field Name         ||Description
-|`message`          |optional|
+|Field Name          ||Description
+|`message`           |optional|
 Commit message for the cherry-pick change. If not set, the commit message of
 the cherry-picked commit is used.
-|`destination`      ||Destination branch
-|`base`             |optional|
+|`destination`       ||Destination branch
+|`base`              |optional|
 40-hex digit SHA-1 of the commit which will be the parent commit of the newly created change.
 If set, it must be a merged commit or a change revision on the destination branch.
-|`parent`           |optional, defaults to 1|
+|`parent`            |optional, defaults to 1|
 Number of the parent relative to which the cherry-pick should be considered.
-|`notify`           |optional|
+|`notify`            |optional|
 Notify handling that defines to whom email notifications should be sent
 after the cherry-pick. +
 Allowed values are `NONE`, `OWNER`, `OWNER_REVIEWERS` and `ALL`. +
 If not set, the default is `ALL`.
-|`notify_details`   |optional|
+|`notify_details`    |optional|
 Additional information about whom to notify about the update as a map
 of link:user-notify.html#recipient-types[recipient type] to
 link:#notify-info[NotifyInfo] entity.
-|`keep_reviewers`   |optional, defaults to false|
+|`keep_reviewers`    |optional, defaults to false|
 If `true`, carries reviewers and ccs over from original change to newly created one.
-|`allow_conflicts`  |optional, defaults to false|
+|`allow_conflicts`   |optional, defaults to false|
 If `true`, the cherry-pick uses content merge and succeeds also if
 there are conflicts. If there are conflicts the file contents of the
 created change contain git conflict markers to indicate the conflicts.
@@ -6836,7 +6792,7 @@
 `contains_git_conflicts` field in the link:#change-info[ChangeInfo]. If
 there are conflicts the cherry-pick change is marked as
 work-in-progress.
-|`topic`            |optional|
+|`topic`             |optional|
 The topic of the created cherry-picked change. If not set, the default depends
 on the source. If the source is a change with a topic, the resulting topic
 of the cherry-picked change will be {source_change_topic}-{destination_branch}.
@@ -6844,10 +6800,18 @@
 the created change will have no topic.
 If the change already exists, the topic will not change if not set. If set, the
 topic will be overridden.
-|`allow_empty`      |optional, defaults to false|
+|`allow_empty`       |optional, defaults to false|
 If `true`, the cherry-pick succeeds also if the created commit will be empty.
 If `false`, a cherry-pick that would create an empty commit fails without creating
 the commit.
+|`validation_options`|optional|
+Map with key-value pairs that are forwarded as options to the commit validation
+listeners (e.g. can be used to skip certain validations). Which validation
+options are supported depends on the installed commit validation listeners.
+Gerrit core doesn't support any validation options, but commit validation
+listeners that are implemented in plugins may. Please refer to the
+documentation of the installed plugins to learn whether they support validation
+options. Unknown validation options are silently ignored.
 |===========================
 
 [[comment-info]]
@@ -7113,6 +7077,9 @@
 Additional information about whom to notify about the update as a map
 of link:user-notify.html#recipient-types[recipient type] to
 link:#notify-info[NotifyInfo] entity.
+|`ignore_automatic_attention_set_rules`|optional|
+If set to true, ignore all automatic attention set rules described in the
+link:#attention-set[attention set]. When not set, the default is false.
 |=============================
 
 [[description-input]]
@@ -7164,7 +7131,11 @@
 |==========================
 |Field Name    ||Description
 |`name`        ||The name of the file.
-|`content_type`||The content type of the file.
+|`content_type`||The content type of the file. For the commit message and merge
+list the value is `text/x-gerrit-commit-message` and `text/x-gerrit-merge-list`
+respectively. For git links the value is `x-git/gitlink`. For symlinks the value
+is `x-git/symlink`. For regular files the value is the file mime type (e.g.
+`text/x-java`, `text/x-c++src`, etc...).
 |`lines`       ||The total number of lines in the file.
 |`web_links`   |optional|
 Links to the file in external sites as a list of
@@ -7433,11 +7404,10 @@
 There are two options that control the contents of `LabelInfo`:
 link:#labels[`LABELS`] and link:#detailed-labels[`DETAILED_LABELS`].
 
-* For a quick summary of the state of labels, use `LABELS`.
-* For detailed information about labels, including exact numeric votes for all
-  users and the allowed range of votes for the current user, use `DETAILED_LABELS`.
+* Using `LABELS` will skip the `all.permitted_voting_range` attribute.
+* Using `DETAILED_LABELS` will include the `all.permitted_voting_range`
+  attribute.
 
-==== Common fields
 [options="header",cols="1,^1,5"]
 |===========================
 |Field Name    ||Description
@@ -7445,12 +7415,7 @@
 Whether the label is optional. Optional means the label may be set, but
 it's neither necessary for submission nor does it block submission if
 set.
-|===========================
-
-==== Fields set by `LABELS`
-[options="header",cols="1,^1,5"]
-|===========================
-|Field Name    ||Description
+|`description` |optional| The description of the label.
 |`approved`    |optional|One user who approved this label on the change
 (voted the maximum value) as an
 link:rest-api-accounts.html#account-info[AccountInfo] entity.
@@ -7470,16 +7435,14 @@
 "`+1`"/"`-1`".
 |`default_value`|optional|The default voting value for the label.
 This value may be outside the range specified in permitted_labels.
-|===========================
-
-==== Fields set by `DETAILED_LABELS`
-[options="header",cols="1,^1,5"]
-|===========================
-|Field Name    ||Description
+|votes|optional|A list of integers containing the vote values applied to this
+label at the latest patchset.
 |`all`         |optional|List of all approvals for this label as a list
 of link:#approval-info[ApprovalInfo] entities. Items in this list may
 not represent actual votes cast by users; if a user votes on any label,
-a corresponding ApprovalInfo will appear in this list for all labels.
+a corresponding ApprovalInfo will appear in this list for all labels. +
+The `permitted_voting_range` attribute is only set if the `DETAILED_LABELS`
+option is requested.
 |`values`      |optional|A map of all values that are allowed for this
 label. The map maps the values ("`-2`", "`-1`", " `0`", "`+1`", "`+2`")
 to the value descriptions.
@@ -7697,22 +7660,30 @@
 === RebaseInput
 The `RebaseInput` entity contains information for changing parent when rebasing.
 
-[options="header",width="50%",cols="1,^1,5"]
+[options="header",cols="1,^1,5"]
 |===========================
-|Field Name    ||Description
-|`base`        |optional|
+|Field Name          ||Description
+|`base`              |optional|
 The new parent revision. This can be a ref or a SHA-1 to a concrete patchset. +
 Alternatively, a change number can be specified, in which case the current
 patch set is inferred. +
 Empty string is used for rebasing directly on top of the target branch,
 which effectively breaks dependency towards a parent change.
-|`allow_conflicts`|optional, defaults to false|
+|`allow_conflicts`   |optional, defaults to false|
 If `true`, the rebase also succeeds if there are conflicts. +
 If there are conflicts the file contents of the rebased patch set contain
 git conflict markers to indicate the conflicts. +
 Callers can find out whether there were conflicts by checking the
 `contains_git_conflicts` field in the returned link:#change-info[ChangeInfo]. +
 If there are conflicts the change is marked as work-in-progress.
+|`validation_options`|optional|
+Map with key-value pairs that are forwarded as options to the commit validation
+listeners (e.g. can be used to skip certain validations). Which validation
+options are supported depends on the installed commit validation listeners.
+Gerrit core doesn't support any validation options, but commit validation
+listeners that are implemented in plugins may. Please refer to the
+documentation of the installed plugins to learn whether they support validation
+options. Unknown validation options are silently ignored.
 |===========================
 
 [[related-change-and-commit-info]]
@@ -8272,21 +8243,24 @@
 The `SubmitRequirementExpressionInfo` describes the result of evaluating a
 single submit requirement expression, for example `label:code-review=+2`.
 
-[options="header",cols="1,6"]
+[options="header",cols="1,^1,5"]
 |===========================
-|Field Name      |Description
-|`expression`|
+|Field Name      ||Description
+|`expression`|optional|
 The submit requirement expression as a string, for example
 `branch:refs/heads/foo and label:verified=+1`.
-|`fulfilled`|
+|`fulfilled`||
 True if the submit requirement is fulfilled for the change.
-|`passing_atoms`|
+|`passing_atoms`|optional|
 A list of passing atoms as strings. For the above expression,
 `passing_atoms` can contain ["branch:refs/heads/foo"] if the branch predicate is
 fulfilled for the change.
-|`failing_atoms`|
+|`failing_atoms`|optional|
 A list of failing atoms. This is similar to `passing_atoms` except that it
 contains the list of predicates that are not fulfilled for the change.
+|`error_message`|optional|
+If the submit requirement fails during evaluation, this string will contain
+an error message describing why it failed.
 |===========================
 
 [[submit-requirement-input]]
@@ -8329,7 +8303,8 @@
 Description of the submit requirement.
 |`status`||
 Status describing the result of evaluating the submit requirement. The status
-is one of (`SATISFIED`, `UNSATISFIED`, `OVERRIDDEN`, `NOT_APPLICABLE`, `ERROR`).
+is one of (`SATISFIED`, `UNSATISFIED`, `OVERRIDDEN`, `NOT_APPLICABLE`, `ERROR`,
+`FORCED`).
 |`is_legacy`||
 If true, this submit requirement result was created from a legacy
 link:#submit-record[SubmitRecord]. Otherwise, it was created by evaluating a
@@ -8338,13 +8313,18 @@
 A link:#submit-requirement-expression-info[SubmitRequirementExpressionInfo]
 containing the result of evaluating the applicability expression. Not set if the
 submit requirement did not define an applicability expression.
-|`submittability_expression_result`||
+Note that fields `expression`, `passing_atoms` and `failing_atoms` are always
+omitted for the `applicability_expression_result`.
+|`submittability_expression_result`|optional|
 A link:#submit-requirement-expression-info[SubmitRequirementExpressionInfo]
-containing the result of evaluating the submittability expression.
+containing the result of evaluating the submittability expression. +
+If the submit requirement does not apply, the expression is not evaluated and
+the field is not set.
 |`override_expression_result`|optional|
 A link:#submit-requirement-expression-info[SubmitRequirementExpressionInfo]
-containing the result of evaluating the override expression. Not set if the
-submit requirement did not define an override expression.
+containing the result of evaluating the override expression. +
+Not set if the submit requirement did not define an override expression or
+if it does not apply.
 |===========================
 
 [[submitted-together-info]]
diff --git a/Documentation/rest-api-config.txt b/Documentation/rest-api-config.txt
index 4056816..c32897c 100644
--- a/Documentation/rest-api-config.txt
+++ b/Documentation/rest-api-config.txt
@@ -2008,6 +2008,10 @@
 |`default_theme`           |optional|
 URL to a default Gerrit UI theme plugin, if available.
 Located in `/static/gerrit-theme.js` by default.
+|`submit_requirement_dashboard_columns` ||
+The list of submit requirement names that should be displayed as separate
+columns in the dashboard. If empty, the default is to display all submit
+requirements that are applicable for changes appearing in the dashboard.
 |=======================================
 
 [[sshd-info]]
diff --git a/Documentation/rest-api-projects.txt b/Documentation/rest-api-projects.txt
index 82b6553..413923f 100644
--- a/Documentation/rest-api-projects.txt
+++ b/Documentation/rest-api-projects.txt
@@ -3072,8 +3072,8 @@
       "function": "MaxWithBlock",
       "values": {
         " 0": "No score",
-        "-1": "I would prefer this is not merged as is",
-        "-2": "This shall not be merged",
+        "-1": "I would prefer this is not submitted as is",
+        "-2": "This shall not be submitted",
         "+1": "Looks good to me, but someone else must approve",
         "+2": "Looks good to me, approved"
       },
@@ -3119,8 +3119,8 @@
       "function": "MaxWithBlock",
       "values": {
         " 0": "No score",
-        "-1": "I would prefer this is not merged as is",
-        "-2": "This shall not be merged",
+        "-1": "I would prefer this is not submitted as is",
+        "-2": "This shall not be submitted",
         "+1": "Looks good to me, but someone else must approve",
         "+2": "Looks good to me, approved"
       },
@@ -3137,8 +3137,8 @@
       "function": "MaxWithBlock",
       "values": {
         " 0": "No score",
-        "-1": "I would prefer this is not merged as is",
-        "-2": "This shall not be merged",
+        "-1": "I would prefer this is not submitted as is",
+        "-2": "This shall not be submitted",
         "+1": "Looks good to me, but someone else must approve",
         "+2": "Looks good to me, approved"
       },
@@ -3182,8 +3182,8 @@
     "function": "MaxWithBlock",
     "values": {
       " 0": "No score",
-      "-1": "I would prefer this is not merged as is",
-      "-2": "This shall not be merged",
+      "-1": "I would prefer this is not submitted as is",
+      "-2": "This shall not be submitted",
       "+1": "Looks good to me, but someone else must approve",
       "+2": "Looks good to me, approved"
     },
@@ -3219,8 +3219,8 @@
     "commit_message": "Create Foo Label",
     "values": {
       " 0": "No score",
-      "-1": "I would prefer this is not merged as is",
-      "-2": "This shall not be merged",
+      "-1": "I would prefer this is not submitted as is",
+      "-2": "This shall not be submitted",
       "+1": "Looks good to me, but someone else must approve",
       "+2": "Looks good to me, approved"
     }
@@ -3243,8 +3243,8 @@
     "function": "MaxWithBlock",
     "values": {
       " 0": "No score",
-      "-1": "I would prefer this is not merged as is",
-      "-2": "This shall not be merged",
+      "-1": "I would prefer this is not submitted as is",
+      "-2": "This shall not be submitted",
       "+1": "Looks good to me, but someone else must approve",
       "+2": "Looks good to me, approved"
     },
@@ -3295,8 +3295,8 @@
     "function": "MaxWithBlock",
     "values": {
       " 0": "No score",
-      "-1": "I would prefer this is not merged as is",
-      "-2": "This shall not be merged",
+      "-1": "I would prefer this is not submitted as is",
+      "-2": "This shall not be submitted",
       "+1": "Looks good to me, but someone else must approve",
       "+2": "Looks good to me, approved"
     },
@@ -3377,8 +3377,8 @@
         "name": "Foo-Review",
         "values": {
           " 0": "No score",
-          "-1": "I would prefer this is not merged as is",
-          "-2": "This shall not be merged",
+          "-1": "I would prefer this is not submitted as is",
+          "-2": "This shall not be submitted",
           "+1": "Looks good to me, but someone else must approve",
           "+2": "Looks good to me, approved"
       }
@@ -3547,14 +3547,22 @@
 
 [options="header",cols="1,^2,4"]
 |=======================
-|Field Name||Description
-|`ref`     |optional|
+|Field Name          ||Description
+|`ref`               |optional|
 The name of the branch. The prefix `refs/heads/` can be
 omitted. +
 If set, must match the branch ID in the URL.
-|`revision`|optional|
+|`revision`          |optional|
 The base revision of the new branch. +
 If not set, `HEAD` will be used as base revision.
+|`validation_options`|optional|
+Map with key-value pairs that are forwarded as options to the ref operation
+validation listeners (e.g. can be used to skip certain validations). Which
+validation options are supported depends on the installed ref operation
+validation listeners. Gerrit core doesn't support any validation options, but
+ref operation validation listeners that are implemented in plugins may. Please
+refer to the documentation of the installed plugins to learn whether they
+support validation options. Unknown validation options are silently ignored.
 |=======================
 
 [[check-project-input]]
@@ -3986,6 +3994,8 @@
 |Field Name      ||Description
 |`name`          ||
 The link:config-labels.html#label_name[name] of the label.
+|`description`   |optional|
+The description of the label.
 |`project_name`  ||
 The name of the project in which this label is defined.
 |`function`      ||
@@ -4006,30 +4016,32 @@
 Whether this label can be link:config-labels.html#label_canOverride[overridden]
 by child projects.
 |`copy_any_score`|`false` if not set|
-Whether link:config-labels.html#label_copyAnyScore[copyAnyScore] is set on the
-label.
+*DEPRECATED* Whether link:config-labels.html#label_copyAnyScore[copyAnyScore]
+is set on the label.
 |`copy_condition`|optional|
 See link:config-labels.html#label_copyCondition[copyCondition].
 |`copy_min_score`|`false` if not set|
-Whether link:config-labels.html#label_copyMinScore[copyMinScore] is set on the
-label.
+*DEPRECATED* Whether link:config-labels.html#label_copyMinScore[copyMinScore]
+is set on the label.
 |`copy_max_score`|`false` if not set|
-Whether link:config-labels.html#label_copyMaxScore[copyMaxScore] is set on the
-label.
+*DEPRECATED* Whether link:config-labels.html#label_copyMaxScore[copyMaxScore]
+is set on the label.
 |`copy_all_scores_if_no_change`|`false` if not set|
-Whether link:config-labels.html#label_copyAllScoresIfNoChange[
+*DEPRECATED* Whether link:config-labels.html#label_copyAllScoresIfNoChange[
 copyAllScoresIfNoChange] is set on the label.
 |`copy_all_scores_if_no_code_change`|`false` if not set|
-Whether link:config-labels.html#label_copyAllScoresIfNoCodeChange[
+*DEPRECATED* Whether link:config-labels.html#label_copyAllScoresIfNoCodeChange[
 copyAllScoresIfNoCodeChange] is set on the label.
 |`copy_all_scores_on_trivial_rebase`|`false` if not set|
-Whether link:config-labels.html#label_copyAllScoresOnTrivialRebase[
+*DEPRECATED* Whether link:config-labels.html#label_copyAllScoresOnTrivialRebase[
 copyAllScoresOnTrivialRebase] is set on the label.
 |`copy_all_scores_if_list_of_files_did_not_change`|`false` if not set|
-Whether link:config-labels.html#label_copyAllScoresIfListOfFilesDidNotChange[
+*DEPRECATED* Whether
+link:config-labels.html#label_copyAllScoresIfListOfFilesDidNotChange[
 copyAllScoresIfListOfFilesDidNotChange] is set on the label.
 |`copy_all_scores_on_merge_first_parent_update`|`false` if not set|
-Whether link:config-labels.html#label_copyAllScoresOnMergeFirstParentUpdate[
+*DEPRECATED* Whether
+link:config-labels.html#label_copyAllScoresOnMergeFirstParentUpdate[
 copyAllScoresOnMergeFirstParentUpdate] is set on the label.
 |`copy_values`   |optional|
 List of values that should be copied forward when a new patch set is uploaded.
@@ -4059,6 +4071,8 @@
 For label creation the name is required if this `LabelDefinitionInput` entity
 is contained in a link:#batch-label-input[BatchLabelInput]
 entity.
+|`description`          |optional|
+The new description for the label.
 |`function`      |optional|
 The new link:config-labels.html#label_function[function] of the label (can be
 `MaxWithBlock`, `AnyWithBlock`, `MaxNoBlock`, `NoBlock`, `NoOp` and `PatchSetLock`.
diff --git a/Documentation/user-attention-set.txt b/Documentation/user-attention-set.txt
index 1f67fc7..512f784 100644
--- a/Documentation/user-attention-set.txt
+++ b/Documentation/user-attention-set.txt
@@ -2,8 +2,6 @@
 
 Report a bug or send feedback using
 link:https://bugs.chromium.org/p/gerrit/issues/entry?template=Attention+Set[this Monorail template].
-You can also report a bug through the bug icon in the user hovercard and in the
-reply dialog.
 
 [[whose-turn]]
 == Whose turn is it?
@@ -133,24 +131,6 @@
 Gerrit-Attention: Marian Harbach <mharbach@google.com>
 ----
 
-=== Assignee
-
-While the "Assignee" feature can still be used together with the attention set,
-we do not recommend doing so. Using both features is likely confusing. The
-distinct feature of the "Assignee" compared to the attention set is that only
-one user can be the assignee at the same time. So the assignee can be used to
-single out one person or escalate, if there are multiple reviewers. Since
-*every* reviewer in the attention set is expected to take action, singling out
-is not likely to be important and also still achievable with the attention set.
-Otherwise "Assignee" and "Attention Set" are very much overlapping, so we
-recommend to only use one of them.
-
-If you don't expect action from reviewers, then consider adding them to CC
-instead.
-
-The "Assignee" feature can be turned on/off with the
-link:config-gerrit.html#change.enableAssignee[enableAssignee] config option.
-
 === Bold Changes / Mark Reviewed
 
 Before the attention set feature, changes were bolded in the dashboard when
diff --git a/Documentation/user-notify.txt b/Documentation/user-notify.txt
index 0e658c7..932acab 100644
--- a/Documentation/user-notify.txt
+++ b/Documentation/user-notify.txt
@@ -11,9 +11,9 @@
 
 Those are the available recipient types:
 
-* `to`: The standard To field is used; addresses are visible to all.
-* `cc`: The standard CC field is used; addresses are visible to all.
-* `bcc`: SMTP RCPT TO is used to hide the address.
+* `TO`: The standard To field is used; addresses are visible to all.
+* `CC`: The standard CC field is used; addresses are visible to all.
+* `BCC`: SMTP RCPT TO is used to hide the address.
 
 [[user]]
 == User Level Settings
diff --git a/Documentation/user-search.txt b/Documentation/user-search.txt
index ccc83eb..cc7d5d1 100644
--- a/Documentation/user-search.txt
+++ b/Documentation/user-search.txt
@@ -49,6 +49,10 @@
 returned results. Search can also be performed by typing only a
 text with no operator, which will match against a variety of fields.
 
+Characters in operator values can be escaped by enclosing the value with
+double quotes and escaping characters with a backslash. For example
+`message:"This \"is\" fixing a bug"`.
+
 [[age]]
 age:'AGE'::
 +
@@ -262,6 +266,11 @@
 often combined with 'branch:' and 'project:' operators to select
 all related changes in a series.
 
+[[prefixtopic]]
+prefixtopic:'TOPIC'::
++
+Changes whose designated topic start with 'TOPIC'.
+
 [[inhashtag]]
 inhashtag:'HASHTAG'::
 +
@@ -278,6 +287,12 @@
 Changes whose link:intro-user.html#hashtags[hashtag] matches 'HASHTAG'.
 The match is case-insensitive.
 
+[[prefixhashtag]]
+prefixhashtag:'HASHTAG'::
++
+Changes whose link:intro-user.html#hashtags[hashtag] start with 'HASHTAG'.
+The match is case-insensitive.
+
 [[cherrypickof]]
 cherrypickof:'CHANGE[,PATCHSET]'::
 +
@@ -321,6 +336,12 @@
 message:'MESSAGE'::
 +
 Changes that match 'MESSAGE' arbitrary string in the commit message body.
+By default full text matching is used, but regular expressions can be
+enabled by starting with `^`.
+The link:http://www.brics.dk/automaton/[dk.brics.automaton library,role=external,window=_blank]
+is used for the evaluation of such patterns. Note, that searching with
+regular expressions is limited to the first 32766 bytes of the
+commit message due to limitations in Lucene.
 
 [[comment]]
 comment:'TEXT'::
@@ -406,6 +427,12 @@
 current patch set. 'FOOTER' can be specified verbatim ('<key>: <value>', must
 be quoted) or as '<key>=<value>'. The matching is done case-insensitive.
 
+[[hasfooter-operator]]
+hasfooter:'FOOTERNAME'::
++
+Matches any change that has a commit message with a footer where the footer
+name is equal to 'FOOTERNAME'.The matching is done case-sensitive.
+
 [[star]]
 star:'LABEL'::
 +
@@ -505,6 +532,7 @@
 +
 Same as <<status,status:'STATE'>>.
 
+[[is-submittable]]
 is:submittable::
 +
 True if the change is submittable according to the submit rules for
@@ -516,8 +544,6 @@
 use the
 link:rest-api-changes.html#get-revision-actions[Get Revision Actions]
 API.
-+
-Equivalent to <<submittable,submittable:ok>>.
 
 [[mergeable]]
 is:mergeable::
@@ -563,6 +589,11 @@
 cherry-picked locally using the git cherry-pick command and then
 pushed to Gerrit.
 
+[[pure-revert]]
+is:pure-revert::
++
+True if the change is a pure revert.
+
 [[status]]
 status:open, status:pending, status:new::
 +
@@ -632,16 +663,6 @@
 email address. The special case of `committer:self` will find changes committed
 by the caller.
 
-
-[[submittable]]
-submittable:'SUBMIT_STATUS'::
-+
-Changes having the given submit record status after applying submit
-rules. Valid statuses are in the `status` field of
-link:rest-api-changes.html#submit-record[SubmitRecord]. This operator
-only applies to the top-level status; individual label statuses can be
-searched link:#labels[by label].
-
 [[rule]]
 rule:'SUBMIT_RULE_NAME'::
 +
@@ -649,8 +670,7 @@
 FORCED}. This means that the submit rule has passed and is not blocking the
 change submission. 'SUBMIT_RULE_NAME' should be in the form of
 '$plugin_name~$rule_name'. For gerrit core rules, 'SUBMIT_RULE_NAME' should
-be in the form of '$rule_name' (example: `DefaultSubmitRule`), or
-'gerrit~$rule_name' (example: `gerrit~DefaultSubmitRule`).
+be in the form of 'gerrit~$rule_name' (example: `gerrit~DefaultSubmitRule`).
 
 rule:'SUBMIT_RULE_NAME'='STATUS'::
 +
@@ -770,12 +790,41 @@
 +
 Matches changes with label voted with any score.
 
-`label:Non-Author-Code-Review=need`::
+`label:Code-Review=+1,count=2`::
++
+Matches changes with exactly two +1 votes to the code-review label. The {MAX,
+MIN, ANY} votes can also be used, for example `label:Code-Review=MAX,count=2` is
+equivalent to `label:Code-Review=2,count=2` (if 2 is the maximum positive vote
+for the code review label). The maximum supported value for `count` is 5.
+`count=0` is not allowed and the query request will fail with `400 Bad Request`.
+
+`label:Code-Review=+1,count>=2`::
++
+Matches changes having two or more +1 votes to the code-review label. Can also
+be used with the {MAX, MIN, ANY} label votes. All operators `>`, `>=`, `<`, `<=`
+are supported.
+Note that a query like `label:Code-Review=+1,count<x` will not match with
+changes having zero +1 votes to this label.
+
+`label:Non-Author-Code-Review=need` (deprecated)::
 +
 Matches changes where the submit rules indicate that a label named
 `Non-Author-Code-Review` is needed. (See the
 link:prolog-cookbook.html#NonAuthorCodeReview[Prolog Cookbook] for how
 this label can be configured.)
++
+This operator is also compatible with
+link:config-submit-requirements.html[submit requirement] results. A submit
+requirement name could be used instead of the label name. The submit record
+statuses are mapped to submit requirement result statuses as follows:
++
+  * {`need`, `reject`} -> {`UNSATISFED`}
+  * {`ok`, `may`} -> {`SATISFIED`, `OVERRIDDEN`}
++
+For example, a query like `label:Code-Review=ok` will also match changes
+having a submit requirement with a result that is either `SATISFIED` or
+`OVERRIDDEN`. Users are encouraged not to rely on this operator since submit
+records are deprecated.
 
 `label:Code-Review=+2,aname`::
 `label:Code-Review=ok,aname`::
@@ -813,7 +862,7 @@
 +
 Matches changes that are ready to be submitted according to one common
 label configuration. (For a more general check, use
-link:#submittable[submittable:ok].)
+link:#is-submittable[is:submittable].)
 
 `is:open (label:Verified-1 OR label:Code-Review-2)`::
 `is:open (label:Verified=reject OR label:Code-Review=reject)`::
diff --git a/WORKSPACE b/WORKSPACE
index b3bf30b..fe6b94e 100644
--- a/WORKSPACE
+++ b/WORKSPACE
@@ -31,6 +31,7 @@
 load("//tools/bzl:maven_jar.bzl", "GERRIT", "MAVEN_LOCAL", "maven_jar")
 load("//plugins:external_plugin_deps.bzl", "external_plugin_deps")
 load("//tools:nongoogle.bzl", "declare_nongoogle_deps")
+load("//tools:deps.bzl", "CAFFEINE_VERS", "java_dependencies")
 
 http_archive(
     name = "platforms",
@@ -53,10 +54,10 @@
 
 http_archive(
     name = "com_google_protobuf",
-    sha256 = "d0f5f605d0d656007ce6c8b5a82df3037e1d8fe8b121ed42e536f569dec16113",
-    strip_prefix = "protobuf-3.14.0",
+    sha256 = "3bd7828aa5af4b13b99c191e8b1e884ebfa9ad371b0ce264605d347f135d2568",
+    strip_prefix = "protobuf-3.19.4",
     urls = [
-        "https://github.com/protocolbuffers/protobuf/archive/v3.14.0.tar.gz",
+        "https://github.com/protocolbuffers/protobuf/archive/v3.19.4.tar.gz",
     ],
 )
 
@@ -116,10 +117,10 @@
 # Golang support for PolyGerrit local dev server.
 http_archive(
     name = "io_bazel_rules_go",
-    sha256 = "4d838e2d70b955ef9dd0d0648f673141df1bc1d7ecf5c2d621dcc163f47dd38a",
+    sha256 = "d6b2513456fe2229811da7eb67a444be7785f5323c6708b38d851d2b51e54d83",
     urls = [
-        "https://mirror.bazel.build/github.com/bazelbuild/rules_go/releases/download/v0.24.12/rules_go-v0.24.12.tar.gz",
-        "https://github.com/bazelbuild/rules_go/releases/download/v0.24.12/rules_go-v0.24.12.tar.gz",
+        "https://mirror.bazel.build/github.com/bazelbuild/rules_go/releases/download/v0.30.0/rules_go-v0.30.0.zip",
+        "https://github.com/bazelbuild/rules_go/releases/download/v0.30.0/rules_go-v0.30.0.zip",
     ],
 )
 
@@ -127,14 +128,14 @@
 
 go_rules_dependencies()
 
-go_register_toolchains()
+go_register_toolchains(version = "1.17.6")
 
 http_archive(
     name = "bazel_gazelle",
-    sha256 = "222e49f034ca7a1d1231422cdb67066b885819885c356673cb1f72f748a3c9d4",
+    sha256 = "de69a09dc70417580aabf20a28619bb3ef60d038470c7cf8442fafcf627c21cb",
     urls = [
-        "https://mirror.bazel.build/github.com/bazelbuild/bazel-gazelle/releases/download/v0.22.3/bazel-gazelle-v0.22.3.tar.gz",
-        "https://github.com/bazelbuild/bazel-gazelle/releases/download/v0.22.3/bazel-gazelle-v0.22.3.tar.gz",
+        "https://mirror.bazel.build/github.com/bazelbuild/bazel-gazelle/releases/download/v0.24.0/bazel-gazelle-v0.24.0.tar.gz",
+        "https://github.com/bazelbuild/bazel-gazelle/releases/download/v0.24.0/bazel-gazelle-v0.24.0.tar.gz",
     ],
 )
 
@@ -149,91 +150,19 @@
     importpath = "github.com/howeyc/fsnotify",
 )
 
+register_toolchains("//tools:error_prone_warnings_toolchain_java11_definition")
+
+register_toolchains("//tools:error_prone_warnings_toolchain_java17_definition")
+
 # JGit external repository consumed from git submodule
 local_repository(
     name = "jgit",
     path = "modules/jgit",
 )
 
-ANTLR_VERS = "3.5.2"
+java_dependencies()
 
-maven_jar(
-    name = "java-runtime",
-    artifact = "org.antlr:antlr-runtime:" + ANTLR_VERS,
-    sha1 = "cd9cd41361c155f3af0f653009dcecb08d8b4afd",
-)
-
-maven_jar(
-    name = "stringtemplate",
-    artifact = "org.antlr:stringtemplate:4.0.2",
-    sha1 = "e28e09e2d44d60506a7bcb004d6c23ff35c6ac08",
-)
-
-maven_jar(
-    name = "org-antlr",
-    artifact = "org.antlr:antlr:" + ANTLR_VERS,
-    sha1 = "c4a65c950bfc3e7d04309c515b2177c00baf7764",
-)
-
-maven_jar(
-    name = "antlr27",
-    artifact = "antlr:antlr:2.7.7",
-    attach_source = False,
-    sha1 = "83cd2cd674a217ade95a4bb83a8a14f351f48bd0",
-)
-
-maven_jar(
-    name = "aopalliance",
-    artifact = "aopalliance:aopalliance:1.0",
-    sha1 = "0235ba8b489512805ac13a8f9ea77a1ca5ebe3e8",
-)
-
-maven_jar(
-    name = "javax_inject",
-    artifact = "javax.inject:javax.inject:1",
-    sha1 = "6975da39a7040257bd51d21a231b76c915872d38",
-)
-
-maven_jar(
-    name = "servlet-api",
-    artifact = "javax.servlet:javax.servlet-api:3.1.0",
-    sha1 = "3cd63d075497751784b2fa84be59432f4905bf7c",
-)
-
-maven_jar(
-    name = "jzlib",
-    artifact = "com.jcraft:jzlib:1.1.1",
-    sha1 = "a1551373315ffc2f96130a0e5704f74e151777ba",
-)
-
-maven_jar(
-    name = "javaewah",
-    artifact = "com.googlecode.javaewah:JavaEWAH:1.1.6",
-    attach_source = False,
-    sha1 = "94ad16d728b374d65bd897625f3fbb3da223a2b6",
-)
-
-maven_jar(
-    name = "error-prone-annotations",
-    artifact = "com.google.errorprone:error_prone_annotations:2.3.3",
-    sha1 = "42aa5155a54a87d70af32d4b0d06bf43779de0e2",
-)
-
-maven_jar(
-    name = "gson",
-    artifact = "com.google.code.gson:gson:2.8.5",
-    sha1 = "f645ed69d595b24d4cf8b3fbb64cc505bede8829",
-)
-
-CAFFEINE_VERS = "2.8.5"
-
-maven_jar(
-    name = "caffeine",
-    artifact = "com.github.ben-manes.caffeine:caffeine:" + CAFFEINE_VERS,
-    sha1 = "f0eafef6e1529a44e36549cd9d1fc06d3a57f384",
-)
-
-CAFFEINE_GUAVA_SHA256 = "a7ce6d29c40bccd688815a6734070c55b20cd326351a06886a6144005aa32299"
+CAFFEINE_GUAVA_SHA256 = "6e48965614557ba4d3c55a197e20c38f23a20032ef8aace37e95ed64d2ebc9a6"
 
 # TODO(davido): Rename guava.jar to caffeine-guava.jar on fetch to prevent potential
 # naming collision between caffeine guava adapter and guava library itself.
@@ -253,650 +182,8 @@
     ],
 )
 
-maven_jar(
-    name = "guava-failureaccess",
-    artifact = "com.google.guava:failureaccess:1.0.1",
-    sha1 = "1dcf1de382a0bf95a3d8b0849546c88bac1292c9",
-)
-
-maven_jar(
-    name = "jsch",
-    artifact = "com.jcraft:jsch:0.1.54",
-    sha1 = "da3584329a263616e277e15462b387addd1b208d",
-)
-
-maven_jar(
-    name = "juniversalchardet",
-    artifact = "com.github.albfernandez:juniversalchardet:2.0.0",
-    sha1 = "28c59f58f5adcc307604602e2aa89e2aca14c554",
-)
-
-maven_jar(
-    name = "json-smart",
-    artifact = "net.minidev:json-smart:1.1.1",
-    sha1 = "24a2f903d25e004de30ac602c5b47f2d4e420a59",
-)
-
-maven_jar(
-    name = "args4j",
-    artifact = "args4j:args4j:2.33",
-    sha1 = "bd87a75374a6d6523de82fef51fc3cfe9baf9fc9",
-)
-
-maven_jar(
-    name = "commons-codec",
-    artifact = "commons-codec:commons-codec:1.10",
-    sha1 = "4b95f4897fa13f2cd904aee711aeafc0c5295cd8",
-)
-
-# When upgrading commons-compress, also upgrade tukaani-xz
-maven_jar(
-    name = "commons-compress",
-    artifact = "org.apache.commons:commons-compress:1.18",
-    sha1 = "1191f9f2bc0c47a8cce69193feb1ff0a8bcb37d5",
-)
-
-maven_jar(
-    name = "commons-lang",
-    artifact = "commons-lang:commons-lang:2.6",
-    sha1 = "0ce1edb914c94ebc388f086c6827e8bdeec71ac2",
-)
-
-maven_jar(
-    name = "commons-lang3",
-    artifact = "org.apache.commons:commons-lang3:3.8.1",
-    sha1 = "6505a72a097d9270f7a9e7bf42c4238283247755",
-)
-
-maven_jar(
-    name = "commons-text",
-    artifact = "org.apache.commons:commons-text:1.2",
-    sha1 = "74acdec7237f576c4803fff0c1008ab8a3808b2b",
-)
-
-maven_jar(
-    name = "commons-dbcp",
-    artifact = "commons-dbcp:commons-dbcp:1.4",
-    sha1 = "30be73c965cc990b153a100aaaaafcf239f82d39",
-)
-
-# Transitive dependency of commons-dbcp, do not update without
-# also updating commons-dbcp
-maven_jar(
-    name = "commons-pool",
-    artifact = "commons-pool:commons-pool:1.5.5",
-    sha1 = "7d8ffbdc47aa0c5a8afe5dc2aaf512f369f1d19b",
-)
-
-maven_jar(
-    name = "commons-net",
-    artifact = "commons-net:commons-net:3.6",
-    sha1 = "b71de00508dcb078d2b24b5fa7e538636de9b3da",
-)
-
-maven_jar(
-    name = "commons-validator",
-    artifact = "commons-validator:commons-validator:1.6",
-    sha1 = "e989d1e87cdd60575df0765ed5bac65c905d7908",
-)
-
-maven_jar(
-    name = "automaton",
-    artifact = "dk.brics:automaton:1.12-1",
-    sha1 = "959a0c62f9a5c2309e0ad0b0589c74d69e101241",
-)
-
-COMMONMARK_VERS = "0.10.0"
-
-# commonmark must match the version used in Gitiles
-maven_jar(
-    name = "commonmark",
-    artifact = "com.atlassian.commonmark:commonmark:" + COMMONMARK_VERS,
-    sha1 = "119cb7bedc3570d9ecb64ec69ab7686b5c20559b",
-)
-
-maven_jar(
-    name = "cm-autolink",
-    artifact = "com.atlassian.commonmark:commonmark-ext-autolink:" + COMMONMARK_VERS,
-    sha1 = "a6056a5efbd68f57d420bc51bbc54b28a5d3c56b",
-)
-
-maven_jar(
-    name = "gfm-strikethrough",
-    artifact = "com.atlassian.commonmark:commonmark-ext-gfm-strikethrough:" + COMMONMARK_VERS,
-    sha1 = "40837da951b421b545edddac57012e15fcc9e63c",
-)
-
-maven_jar(
-    name = "gfm-tables",
-    artifact = "com.atlassian.commonmark:commonmark-ext-gfm-tables:" + COMMONMARK_VERS,
-    sha1 = "c075db2a3301100cf70c7dced8ecf86b494458a2",
-)
-
-FLEXMARK_VERS = "0.50.42"
-
-maven_jar(
-    name = "flexmark",
-    artifact = "com.vladsch.flexmark:flexmark:" + FLEXMARK_VERS,
-    sha1 = "ed537d7bc31883b008cc17d243a691c7efd12a72",
-)
-
-maven_jar(
-    name = "flexmark-ext-abbreviation",
-    artifact = "com.vladsch.flexmark:flexmark-ext-abbreviation:" + FLEXMARK_VERS,
-    sha1 = "dc27c3e7abbc8d2cfb154f41c68645c365bb9d22",
-)
-
-maven_jar(
-    name = "flexmark-ext-anchorlink",
-    artifact = "com.vladsch.flexmark:flexmark-ext-anchorlink:" + FLEXMARK_VERS,
-    sha1 = "6a8edb0165f695c9c19b7143a7fbd78c25c3b99c",
-)
-
-maven_jar(
-    name = "flexmark-ext-autolink",
-    artifact = "com.vladsch.flexmark:flexmark-ext-autolink:" + FLEXMARK_VERS,
-    sha1 = "5da7a4d009ea08ef2d8714cc73e54a992c6d2d9a",
-)
-
-maven_jar(
-    name = "flexmark-ext-definition",
-    artifact = "com.vladsch.flexmark:flexmark-ext-definition:" + FLEXMARK_VERS,
-    sha1 = "862d17812654624ed81ce8fc89c5ef819ff45f87",
-)
-
-maven_jar(
-    name = "flexmark-ext-emoji",
-    artifact = "com.vladsch.flexmark:flexmark-ext-emoji:" + FLEXMARK_VERS,
-    sha1 = "f0d7db64cb546798742b1ffc6db316a33f6acd76",
-)
-
-maven_jar(
-    name = "flexmark-ext-escaped-character",
-    artifact = "com.vladsch.flexmark:flexmark-ext-escaped-character:" + FLEXMARK_VERS,
-    sha1 = "6fd9ab77619df417df949721cb29c45914b326f8",
-)
-
-maven_jar(
-    name = "flexmark-ext-footnotes",
-    artifact = "com.vladsch.flexmark:flexmark-ext-footnotes:" + FLEXMARK_VERS,
-    sha1 = "e36bd69e43147cc6e19c3f55e4b27c0fc5a3d88c",
-)
-
-maven_jar(
-    name = "flexmark-ext-gfm-issues",
-    artifact = "com.vladsch.flexmark:flexmark-ext-gfm-issues:" + FLEXMARK_VERS,
-    sha1 = "5c825dd4e4fa4f7ccbe30dc92d7e35cdcb8a8c24",
-)
-
-maven_jar(
-    name = "flexmark-ext-gfm-strikethrough",
-    artifact = "com.vladsch.flexmark:flexmark-ext-gfm-strikethrough:" + FLEXMARK_VERS,
-    sha1 = "3256735fd77e7228bf40f7888b4d3dc56787add4",
-)
-
-maven_jar(
-    name = "flexmark-ext-gfm-tables",
-    artifact = "com.vladsch.flexmark:flexmark-ext-gfm-tables:" + FLEXMARK_VERS,
-    sha1 = "62f0efcfb974756940ebe749fd4eb01323babc29",
-)
-
-maven_jar(
-    name = "flexmark-ext-gfm-tasklist",
-    artifact = "com.vladsch.flexmark:flexmark-ext-gfm-tasklist:" + FLEXMARK_VERS,
-    sha1 = "76d4971ad9ce02f0e70351ab6bd06ad8e405e40d",
-)
-
-maven_jar(
-    name = "flexmark-ext-gfm-users",
-    artifact = "com.vladsch.flexmark:flexmark-ext-gfm-users:" + FLEXMARK_VERS,
-    sha1 = "7b0fc7e42e4da508da167fcf8e1cbf9ba7e21147",
-)
-
-maven_jar(
-    name = "flexmark-ext-ins",
-    artifact = "com.vladsch.flexmark:flexmark-ext-ins:" + FLEXMARK_VERS,
-    sha1 = "9e51809867b9c4db0fb1c29599b4574e3d2a78e9",
-)
-
-maven_jar(
-    name = "flexmark-ext-jekyll-front-matter",
-    artifact = "com.vladsch.flexmark:flexmark-ext-jekyll-front-matter:" + FLEXMARK_VERS,
-    sha1 = "44eb6dbb33b3831d3b40af938ddcd99c9c16a654",
-)
-
-maven_jar(
-    name = "flexmark-ext-superscript",
-    artifact = "com.vladsch.flexmark:flexmark-ext-superscript:" + FLEXMARK_VERS,
-    sha1 = "35815b8cb91000344d1fe5df21cacde8553d2994",
-)
-
-maven_jar(
-    name = "flexmark-ext-tables",
-    artifact = "com.vladsch.flexmark:flexmark-ext-tables:" + FLEXMARK_VERS,
-    sha1 = "f6768e98c7210b79d5e8bab76fff27eec6db51e6",
-)
-
-maven_jar(
-    name = "flexmark-ext-toc",
-    artifact = "com.vladsch.flexmark:flexmark-ext-toc:" + FLEXMARK_VERS,
-    sha1 = "1968d038fc6c8156f244f5a7eecb34e7e2f33705",
-)
-
-maven_jar(
-    name = "flexmark-ext-typographic",
-    artifact = "com.vladsch.flexmark:flexmark-ext-typographic:" + FLEXMARK_VERS,
-    sha1 = "6549b9862b61c4434a855a733237103df9162849",
-)
-
-maven_jar(
-    name = "flexmark-ext-wikilink",
-    artifact = "com.vladsch.flexmark:flexmark-ext-wikilink:" + FLEXMARK_VERS,
-    sha1 = "e105b09dd35aab6e6f5c54dfe062ee59bd6f786a",
-)
-
-maven_jar(
-    name = "flexmark-ext-yaml-front-matter",
-    artifact = "com.vladsch.flexmark:flexmark-ext-yaml-front-matter:" + FLEXMARK_VERS,
-    sha1 = "b2d3a1e7f3985841062e8d3203617e29c6c21b52",
-)
-
-maven_jar(
-    name = "flexmark-formatter",
-    artifact = "com.vladsch.flexmark:flexmark-formatter:" + FLEXMARK_VERS,
-    sha1 = "a50c6cb10f6d623fc4354a572c583de1372d217f",
-)
-
-maven_jar(
-    name = "flexmark-html-parser",
-    artifact = "com.vladsch.flexmark:flexmark-html-parser:" + FLEXMARK_VERS,
-    sha1 = "46c075f30017e131c1ada8538f1d8eacf652b044",
-)
-
-maven_jar(
-    name = "flexmark-profile-pegdown",
-    artifact = "com.vladsch.flexmark:flexmark-profile-pegdown:" + FLEXMARK_VERS,
-    sha1 = "d9aafd47629959cbeddd731f327ae090fc92b60f",
-)
-
-maven_jar(
-    name = "flexmark-util",
-    artifact = "com.vladsch.flexmark:flexmark-util:" + FLEXMARK_VERS,
-    sha1 = "417a9821d5d80ddacbfecadc6843ae7b259d5112",
-)
-
-# Transitive dependency of flexmark and gitiles
-maven_jar(
-    name = "autolink",
-    artifact = "org.nibor.autolink:autolink:0.7.0",
-    sha1 = "649f9f13422cf50c926febe6035662ae25dc89b2",
-)
-
-GREENMAIL_VERS = "1.5.5"
-
-maven_jar(
-    name = "greenmail",
-    artifact = "com.icegreen:greenmail:" + GREENMAIL_VERS,
-    sha1 = "9ea96384ad2cb8118c22f493b529eb72c212691c",
-)
-
-MAIL_VERS = "1.6.0"
-
-maven_jar(
-    name = "mail",
-    artifact = "com.sun.mail:javax.mail:" + MAIL_VERS,
-    sha1 = "a055c648842c4954c1f7db7254f45d9ad565e278",
-)
-
-MIME4J_VERS = "0.8.1"
-
-maven_jar(
-    name = "mime4j-core",
-    artifact = "org.apache.james:apache-mime4j-core:" + MIME4J_VERS,
-    sha1 = "c62dfe18a3b827a2c626ade0ffba44562ddf3f61",
-)
-
-maven_jar(
-    name = "mime4j-dom",
-    artifact = "org.apache.james:apache-mime4j-dom:" + MIME4J_VERS,
-    sha1 = "f2d653c617004193f3350330d907f77b60c88c56",
-)
-
-maven_jar(
-    name = "jsoup",
-    artifact = "org.jsoup:jsoup:1.9.2",
-    sha1 = "5e3bda828a80c7a21dfbe2308d1755759c2fd7b4",
-)
-
-OW2_VERS = "9.0"
-
-maven_jar(
-    name = "ow2-asm",
-    artifact = "org.ow2.asm:asm:" + OW2_VERS,
-    sha1 = "af582ff60bc567c42d931500c3fdc20e0141ddf9",
-)
-
-maven_jar(
-    name = "ow2-asm-analysis",
-    artifact = "org.ow2.asm:asm-analysis:" + OW2_VERS,
-    sha1 = "4630afefbb43939c739445dde0af1a5729a0fb4e",
-)
-
-maven_jar(
-    name = "ow2-asm-commons",
-    artifact = "org.ow2.asm:asm-commons:" + OW2_VERS,
-    sha1 = "5a34a3a9ac44f362f35d1b27932380b0031a3334",
-)
-
-maven_jar(
-    name = "ow2-asm-tree",
-    artifact = "org.ow2.asm:asm-tree:" + OW2_VERS,
-    sha1 = "9df939f25c556b0c7efe00701d47e77a49837f24",
-)
-
-maven_jar(
-    name = "ow2-asm-util",
-    artifact = "org.ow2.asm:asm-util:" + OW2_VERS,
-    sha1 = "7c059a94ab5eed3347bf954e27fab58e52968848",
-)
-
-AUTO_VALUE_VERSION = "1.7.4"
-
-maven_jar(
-    name = "auto-value",
-    artifact = "com.google.auto.value:auto-value:" + AUTO_VALUE_VERSION,
-    sha1 = "6b126cb218af768339e4d6e95a9b0ae41f74e73d",
-)
-
-maven_jar(
-    name = "auto-value-annotations",
-    artifact = "com.google.auto.value:auto-value-annotations:" + AUTO_VALUE_VERSION,
-    sha1 = "eff48ed53995db2dadf0456426cc1f8700136f86",
-)
-
-AUTO_VALUE_GSON_VERSION = "1.3.1"
-
-maven_jar(
-    name = "auto-value-gson-runtime",
-    artifact = "com.ryanharter.auto.value:auto-value-gson-runtime:" + AUTO_VALUE_GSON_VERSION,
-    sha1 = "addda2ae6cce9f855788274df5de55dde4de7b71",
-)
-
-maven_jar(
-    name = "auto-value-gson-extension",
-    artifact = "com.ryanharter.auto.value:auto-value-gson-extension:" + AUTO_VALUE_GSON_VERSION,
-    sha1 = "0c4c01a3e10e5b10df2e5f5697efa4bb3f453ac1",
-)
-
-maven_jar(
-    name = "auto-value-gson-factory",
-    artifact = "com.ryanharter.auto.value:auto-value-gson-factory:" + AUTO_VALUE_GSON_VERSION,
-    sha1 = "9ed8d79144ee8d60cc94cc11f847b5ed8ee9f19c",
-)
-
-maven_jar(
-    name = "javapoet",
-    artifact = "com.squareup:javapoet:1.13.0",
-    sha1 = "d6562d385049f35eb50403fa86bb11cce76b866a",
-)
-
-maven_jar(
-    name = "autotransient",
-    artifact = "io.sweers.autotransient:autotransient:1.0.0",
-    sha1 = "38b1c630b8e76560221622289f37be40105abb3d",
-)
-
 declare_nongoogle_deps()
 
-maven_jar(
-    name = "mime-util",
-    artifact = "eu.medsea.mimeutil:mime-util:2.1.3",
-    attach_source = False,
-    sha1 = "0c9cfae15c74f62491d4f28def0dff1dabe52a47",
-)
-
-PROLOG_VERS = "1.4.4"
-
-PROLOG_REPO = GERRIT
-
-maven_jar(
-    name = "prolog-runtime",
-    artifact = "com.googlecode.prolog-cafe:prolog-runtime:" + PROLOG_VERS,
-    attach_source = False,
-    repository = PROLOG_REPO,
-    sha1 = "e9a364f4233481cce63239e8e68a6190c8f58acd",
-)
-
-maven_jar(
-    name = "prolog-compiler",
-    artifact = "com.googlecode.prolog-cafe:prolog-compiler:" + PROLOG_VERS,
-    attach_source = False,
-    repository = PROLOG_REPO,
-    sha1 = "570295026f6aa7b905e423d107cb2e081eecdc04",
-)
-
-maven_jar(
-    name = "prolog-io",
-    artifact = "com.googlecode.prolog-cafe:prolog-io:" + PROLOG_VERS,
-    attach_source = False,
-    repository = PROLOG_REPO,
-    sha1 = "1f25c4e27d22bdbc31481ee0c962a2a2853e4428",
-)
-
-maven_jar(
-    name = "cafeteria",
-    artifact = "com.googlecode.prolog-cafe:prolog-cafeteria:" + PROLOG_VERS,
-    attach_source = False,
-    repository = PROLOG_REPO,
-    sha1 = "0e6c2deeaf5054815a561cbd663566fd59b56c6c",
-)
-
-maven_jar(
-    name = "guava-retrying",
-    artifact = "com.github.rholder:guava-retrying:2.0.0",
-    sha1 = "974bc0a04a11cc4806f7c20a34703bd23c34e7f4",
-)
-
-maven_jar(
-    name = "jsr305",
-    artifact = "com.google.code.findbugs:jsr305:3.0.1",
-    sha1 = "f7be08ec23c21485b9b5a1cf1654c2ec8c58168d",
-)
-
-GITILES_VERS = "0.4-1"
-
-GITILES_REPO = GERRIT
-
-maven_jar(
-    name = "blame-cache",
-    artifact = "com.google.gitiles:blame-cache:" + GITILES_VERS,
-    attach_source = False,
-    repository = GITILES_REPO,
-    sha1 = "0df80c6b8822147e1f116fd7804b8a0de544f402",
-)
-
-maven_jar(
-    name = "gitiles-servlet",
-    artifact = "com.google.gitiles:gitiles-servlet:" + GITILES_VERS,
-    repository = GITILES_REPO,
-    sha1 = "60870897d22b840e65623fd024eabd9cc9706ebe",
-)
-
-# prettify must match the version used in Gitiles
-maven_jar(
-    name = "prettify",
-    artifact = "com.github.twalcari:java-prettify:1.2.2",
-    sha1 = "b8ba1c1eb8b2e45cfd465d01218c6060e887572e",
-)
-
-maven_jar(
-    name = "html-types",
-    artifact = "com.google.common.html.types:types:1.0.8",
-    sha1 = "9e9cf7bc4b2a60efeb5f5581fe46d17c068e0777",
-)
-
-maven_jar(
-    name = "icu4j",
-    artifact = "com.ibm.icu:icu4j:57.1",
-    sha1 = "198ea005f41219f038f4291f0b0e9f3259730e92",
-)
-
-# When updating Bouncy Castle, also update it in bazlets.
-BC_VERS = "1.61"
-
-maven_jar(
-    name = "bcprov",
-    artifact = "org.bouncycastle:bcprov-jdk15on:" + BC_VERS,
-    sha1 = "00df4b474e71be02c1349c3292d98886f888d1f7",
-)
-
-maven_jar(
-    name = "bcpg",
-    artifact = "org.bouncycastle:bcpg-jdk15on:" + BC_VERS,
-    sha1 = "422656435514ab8a28752b117d5d2646660a0ace",
-)
-
-maven_jar(
-    name = "bcpkix",
-    artifact = "org.bouncycastle:bcpkix-jdk15on:" + BC_VERS,
-    sha1 = "89bb3aa5b98b48e584eee2a7401b7682a46779b4",
-)
-
-maven_jar(
-    name = "h2",
-    artifact = "com.h2database:h2:1.3.176",
-    sha1 = "fd369423346b2f1525c413e33f8cf95b09c92cbd",
-)
-
-HTTPCOMP_VERS = "4.5.2"
-
-maven_jar(
-    name = "fluent-hc",
-    artifact = "org.apache.httpcomponents:fluent-hc:" + HTTPCOMP_VERS,
-    sha1 = "7bfdfa49de6d720ad3c8cedb6a5238eec564dfed",
-)
-
-maven_jar(
-    name = "httpclient",
-    artifact = "org.apache.httpcomponents:httpclient:" + HTTPCOMP_VERS,
-    sha1 = "733db77aa8d9b2d68015189df76ab06304406e50",
-)
-
-maven_jar(
-    name = "httpcore",
-    artifact = "org.apache.httpcomponents:httpcore:4.4.4",
-    sha1 = "b31526a230871fbe285fbcbe2813f9c0839ae9b0",
-)
-
-# Test-only dependencies below.
-
-maven_jar(
-    name = "junit",
-    artifact = "junit:junit:4.12",
-    sha1 = "2973d150c0dc1fefe998f834810d68f278ea58ec",
-)
-
-maven_jar(
-    name = "diffutils",
-    artifact = "com.googlecode.java-diff-utils:diffutils:1.3.0",
-    sha1 = "7e060dd5b19431e6d198e91ff670644372f60fbd",
-)
-
-JETTY_VERS = "9.4.36.v20210114"
-
-maven_jar(
-    name = "jetty-servlet",
-    artifact = "org.eclipse.jetty:jetty-servlet:" + JETTY_VERS,
-    sha1 = "b189e52a5ee55ae172e4e99e29c5c314f5daf4b9",
-)
-
-maven_jar(
-    name = "jetty-security",
-    artifact = "org.eclipse.jetty:jetty-security:" + JETTY_VERS,
-    sha1 = "42030d6ed7dfc0f75818cde0adcf738efc477574",
-)
-
-maven_jar(
-    name = "jetty-server",
-    artifact = "org.eclipse.jetty:jetty-server:" + JETTY_VERS,
-    sha1 = "88a7d342974aadca658e7386e8d0fcc5c0788f41",
-)
-
-maven_jar(
-    name = "jetty-jmx",
-    artifact = "org.eclipse.jetty:jetty-jmx:" + JETTY_VERS,
-    sha1 = "bb3847eabe085832aeaedd30e872b40931632e54",
-)
-
-maven_jar(
-    name = "jetty-http",
-    artifact = "org.eclipse.jetty:jetty-http:" + JETTY_VERS,
-    sha1 = "1eee89a55e04ff94df0f85d95200fc48acb43d86",
-)
-
-maven_jar(
-    name = "jetty-io",
-    artifact = "org.eclipse.jetty:jetty-io:" + JETTY_VERS,
-    sha1 = "84a8faf9031eb45a5a2ddb7681e22c483d81ab3a",
-)
-
-maven_jar(
-    name = "jetty-util",
-    artifact = "org.eclipse.jetty:jetty-util:" + JETTY_VERS,
-    sha1 = "925257fbcca6b501a25252c7447dbedb021f7404",
-)
-
-maven_jar(
-    name = "jetty-util-ajax",
-    artifact = "org.eclipse.jetty:jetty-util-ajax:" + JETTY_VERS,
-    sha1 = "2f478130c21787073facb64d7242e06f94980c60",
-    src_sha1 = "7153d7ca38878d971fd90992c303bb7719ba7a21",
-)
-
-maven_jar(
-    name = "asciidoctor",
-    artifact = "org.asciidoctor:asciidoctorj:1.5.7",
-    sha1 = "8e8c1d8fc6144405700dd8df3b177f2801ac5987",
-)
-
-maven_jar(
-    name = "javax-activation",
-    artifact = "javax.activation:activation:1.1.1",
-    sha1 = "485de3a253e23f645037828c07f1d7f1af40763a",
-)
-
-maven_jar(
-    name = "javax-annotation",
-    artifact = "javax.annotation:javax.annotation-api:1.3.2",
-    sha1 = "934c04d3cfef185a8008e7bf34331b79730a9d43",
-)
-
-maven_jar(
-    name = "mockito",
-    artifact = "org.mockito:mockito-core:3.3.3",
-    sha1 = "4878395d4e63173f3825e17e5e0690e8054445f1",
-)
-
-BYTE_BUDDY_VERSION = "1.10.7"
-
-maven_jar(
-    name = "bytebuddy",
-    artifact = "net.bytebuddy:byte-buddy:" + BYTE_BUDDY_VERSION,
-    sha1 = "1eefb7dd1b032b33c773ca0a17d5cc9e6b56ea1a",
-)
-
-maven_jar(
-    name = "bytebuddy-agent",
-    artifact = "net.bytebuddy:byte-buddy-agent:" + BYTE_BUDDY_VERSION,
-    sha1 = "c472fad33f617228601172682aa64f8b78508045",
-)
-
-maven_jar(
-    name = "objenesis",
-    artifact = "org.objenesis:objenesis:3.0.1",
-    sha1 = "11cfac598df9dc48bb9ed9357ed04212694b7808",
-)
-
 load("@build_bazel_rules_nodejs//:index.bzl", "node_repositories", "yarn_install")
 
 node_repositories(
diff --git a/antlr3/com/google/gerrit/index/query/Query.g b/antlr3/com/google/gerrit/index/query/Query.g
index 1bf20aa..0994d9b 100644
--- a/antlr3/com/google/gerrit/index/query/Query.g
+++ b/antlr3/com/google/gerrit/index/query/Query.g
@@ -152,18 +152,19 @@
   :  ( ' ' | '\r' | '\t' | '\n' ) { $channel=HIDDEN; }
   ;
 
+fragment LOWERCASE_AND_UNDERSCORE: ('a'..'z' | '_')+ ;
+
 FIELD_NAME
-  : ('a'..'z' | '_')+
+  : LOWERCASE_AND_UNDERSCORE ( '-' LOWERCASE_AND_UNDERSCORE )*
   ;
 
 EXACT_PHRASE
-  : '"' ( ~('"') )* '"' {
-      String s = $text;
-      setText(s.substring(1, s.length() - 1));
+@init { final StringBuilder buf = new StringBuilder(); }
+  : '"' ( ESCAPE[buf] | i = ~('\\'|'"') { buf.appendCodePoint(i); } )* '"' {
+      setText(buf.toString());
     }
-  | '{' ( ~('{'|'}') )* '}' {
-      String s = $text;
-      setText(s.substring(1, s.length() - 1));
+  | '{' ( ESCAPE[buf] | i = ~('\\'|'{'|'}') { buf.appendCodePoint(i); } )* '}' {
+      setText(buf.toString());
     }
   ;
 
@@ -197,3 +198,11 @@
      // | '~' permit
      )
   ;
+
+fragment ESCAPE[StringBuilder buf] :
+    '\\'
+    ( 't' { buf.append('\t'); }
+    | 'n' { buf.append('\n'); }
+    | 'r' { buf.append('\r'); }
+    | i = ~('t'|'n'|'r') { buf.appendCodePoint(i); }
+    );
diff --git a/contrib/convertkey/src/main/java/com/googlesource/gerrit/convertkey/ConvertKey.java b/contrib/convertkey/src/main/java/com/googlesource/gerrit/convertkey/ConvertKey.java
deleted file mode 100644
index 08a529c..0000000
--- a/contrib/convertkey/src/main/java/com/googlesource/gerrit/convertkey/ConvertKey.java
+++ /dev/null
@@ -1,69 +0,0 @@
-// Copyright (C) 2015 The Android Open Source Project
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package com.googlesource.gerrit.convertkey;
-
-import com.jcraft.jsch.HostKey;
-import com.jcraft.jsch.JSchException;
-import java.io.File;
-import java.io.IOException;
-import java.io.StringWriter;
-import java.security.GeneralSecurityException;
-import java.security.KeyPair;
-import org.apache.sshd.common.util.Buffer;
-import org.apache.sshd.server.keyprovider.SimpleGeneratorHostKeyProvider;
-import org.bouncycastle.openssl.jcajce.JcaPEMWriter;
-
-public class ConvertKey {
-  public static void main(String[] args)
-      throws GeneralSecurityException, JSchException, IOException {
-    SimpleGeneratorHostKeyProvider p;
-
-    if (args.length != 1) {
-      System.err.println("Error: requires path to the SSH host key");
-      return;
-    } else {
-      File file = new File(args[0]);
-      if (!file.exists() || !file.isFile() || !file.canRead()) {
-        System.err.println("Error: ssh key should exist and be readable");
-        return;
-      }
-    }
-
-    p = new SimpleGeneratorHostKeyProvider();
-    // Gerrit's SSH "simple" keys are always RSA.
-    p.setPath(args[0]);
-    p.setAlgorithm("RSA");
-    Iterable<KeyPair> keys = p.loadKeys(); // forces the key to generate.
-    for (KeyPair k : keys) {
-      System.out.println("Public Key (" + k.getPublic().getAlgorithm() + "):");
-      // From Gerrit's SshDaemon class; use JSch to get the public
-      // key/type
-      final Buffer buf = new Buffer();
-      buf.putRawPublicKey(k.getPublic());
-      final byte[] keyBin = buf.getCompactData();
-      HostKey pub = new HostKey("localhost", keyBin);
-      System.out.println(pub.getType() + " " + pub.getKey());
-      System.out.println("Private Key:");
-      // Use Bouncy Castle to write the private key back in PEM format
-      // (PKCS#1)
-      // http://stackoverflow.com/questions/25129822/export-rsa-public-key-to-pem-string-using-java
-      StringWriter privout = new StringWriter();
-      JcaPEMWriter privWriter = new JcaPEMWriter(privout);
-      privWriter.writeObject(k.getPrivate());
-      privWriter.close();
-      System.out.println(privout);
-    }
-  }
-}
diff --git a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/AbandonChange.json b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/AbandonChange.json
index 665cc4d..9d24b5b 100644
--- a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/AbandonChange.json
+++ b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/AbandonChange.json
@@ -1,6 +1,6 @@
 [
   {
-    "url": "HTTP_SCHEME://HOSTNAME:HTTP_PORT/a/changes/",
+    "url": "HTTP_SCHEME://HOSTNAME:HTTP_PORTCONTEXT_PATH/a/changes/",
     "number": "NUMBER"
   }
 ]
diff --git a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/ApproveChange.json b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/ApproveChange.json
index 665cc4d..9d24b5b 100644
--- a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/ApproveChange.json
+++ b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/ApproveChange.json
@@ -1,6 +1,6 @@
 [
   {
-    "url": "HTTP_SCHEME://HOSTNAME:HTTP_PORT/a/changes/",
+    "url": "HTTP_SCHEME://HOSTNAME:HTTP_PORTCONTEXT_PATH/a/changes/",
     "number": "NUMBER"
   }
 ]
diff --git a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/CheckMasterBranchReplica1.json b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/CheckMasterBranchReplica1.json
index 5b892aa..594903a 100644
--- a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/CheckMasterBranchReplica1.json
+++ b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/CheckMasterBranchReplica1.json
@@ -1,5 +1,5 @@
 [
   {
-    "url": "HTTP_SCHEME://HOSTNAME:HTTP_PORT1/a/projects/PROJECT/branches/master"
+    "url": "HTTP_SCHEME://REPLICA_HOSTNAME:HTTP_PORT1/a/projects/PROJECT/branches/master"
   }
 ]
diff --git a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/CheckNewProjectReplica1.json b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/CheckNewProjectReplica1.json
index f15ddae..5221d95 100644
--- a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/CheckNewProjectReplica1.json
+++ b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/CheckNewProjectReplica1.json
@@ -1,6 +1,6 @@
 [
   {
-    "url": "HTTP_SCHEME://HOSTNAME:HTTP_PORT1/_PROJECT",
+    "url": "HTTP_SCHEME://REPLICA_HOSTNAME:HTTP_PORT1/_PROJECT",
     "cmd": "clone"
   }
 ]
diff --git a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/CheckProjectsCacheFlushEntries.json b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/CheckProjectsCacheFlushEntries.json
index 467661b..75e895e 100644
--- a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/CheckProjectsCacheFlushEntries.json
+++ b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/CheckProjectsCacheFlushEntries.json
@@ -1,6 +1,6 @@
 [
   {
-    "url": "HTTP_SCHEME://HOSTNAME:HTTP_PORT/a/config/server/caches/projects",
+    "url": "HTTP_SCHEME://HOSTNAME:HTTP_PORTCONTEXT_PATH/a/config/server/caches/projects",
     "entries": "PROJECTS_ENTRIES"
   }
 ]
diff --git a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/CloneUsingBothProtocols.json b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/CloneUsingBothProtocols.json
index 30f5f23..195ed09 100644
--- a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/CloneUsingBothProtocols.json
+++ b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/CloneUsingBothProtocols.json
@@ -1,10 +1,10 @@
 [
   {
-    "url": "ssh://admin@HOSTNAME:SSH_PORT/_PROJECT",
+    "url": "ssh://USERNAME@HOSTNAME:SSH_PORT/_PROJECT",
     "cmd": "clone"
   },
   {
-    "url": "HTTP_SCHEME://HOSTNAME:HTTP_PORT/_PROJECT",
+    "url": "HTTP_SCHEME://HOSTNAME:HTTP_PORTCONTEXT_PATH/_PROJECT",
     "cmd": "clone"
   }
 ]
diff --git a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/CreateBranch.json b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/CreateBranch.json
index 5459f11..487cf02 100644
--- a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/CreateBranch.json
+++ b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/CreateBranch.json
@@ -1,6 +1,6 @@
 [
   {
-    "url": "HTTP_SCHEME://HOSTNAME:HTTP_PORT/a/projects/PROJECT/branches/",
+    "url": "HTTP_SCHEME://HOSTNAME:HTTP_PORTCONTEXT_PATH/a/projects/PROJECT/branches/",
     "project": "PROJECT"
   }
 ]
diff --git a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/CreateChange.json b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/CreateChange.json
index 70e79ca..8b8a163 100644
--- a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/CreateChange.json
+++ b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/CreateChange.json
@@ -1,6 +1,6 @@
 [
   {
-    "url": "HTTP_SCHEME://HOSTNAME:HTTP_PORT/a/changes/",
+    "url": "HTTP_SCHEME://HOSTNAME:HTTP_PORTCONTEXT_PATH/a/changes/",
     "project": "PROJECT"
   }
 ]
diff --git a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/CreateProject.json b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/CreateProject.json
index c141bb8..756313a 100644
--- a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/CreateProject.json
+++ b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/CreateProject.json
@@ -1,6 +1,6 @@
 [
   {
-    "url": "HTTP_SCHEME://HOSTNAME:HTTP_PORT/a/projects/PROJECT",
+    "url": "HTTP_SCHEME://HOSTNAME:HTTP_PORTCONTEXT_PATH/a/projects/PROJECT",
     "parent": "PARENT"
   }
 ]
diff --git a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/DeleteChange.json b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/DeleteChange.json
index 665cc4d..9d24b5b 100644
--- a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/DeleteChange.json
+++ b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/DeleteChange.json
@@ -1,6 +1,6 @@
 [
   {
-    "url": "HTTP_SCHEME://HOSTNAME:HTTP_PORT/a/changes/",
+    "url": "HTTP_SCHEME://HOSTNAME:HTTP_PORTCONTEXT_PATH/a/changes/",
     "number": "NUMBER"
   }
 ]
diff --git a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/DeleteProject.json b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/DeleteProject.json
index 5720f53..8bec9de 100644
--- a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/DeleteProject.json
+++ b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/DeleteProject.json
@@ -1,5 +1,5 @@
 [
   {
-    "url": "HTTP_SCHEME://HOSTNAME:HTTP_PORT/a/projects/PROJECT/delete-project~delete"
+    "url": "HTTP_SCHEME://HOSTNAME:HTTP_PORTCONTEXT_PATH/a/projects/PROJECT/delete-project~delete"
   }
 ]
diff --git a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/FlushProjectsCache.json b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/FlushProjectsCache.json
index e30a2cf..c1dc674 100644
--- a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/FlushProjectsCache.json
+++ b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/FlushProjectsCache.json
@@ -1,5 +1,5 @@
 [
   {
-    "url": "HTTP_SCHEME://HOSTNAME:HTTP_PORT/a/config/server/caches/projects/flush"
+    "url": "HTTP_SCHEME://HOSTNAME:HTTP_PORTCONTEXT_PATH/a/config/server/caches/projects/flush"
   }
 ]
diff --git a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/FlushProjectsCacheThenRebuild.json b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/FlushProjectsCacheThenRebuild.json
index e30a2cf..c1dc674 100644
--- a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/FlushProjectsCacheThenRebuild.json
+++ b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/FlushProjectsCacheThenRebuild.json
@@ -1,5 +1,5 @@
 [
   {
-    "url": "HTTP_SCHEME://HOSTNAME:HTTP_PORT/a/config/server/caches/projects/flush"
+    "url": "HTTP_SCHEME://HOSTNAME:HTTP_PORTCONTEXT_PATH/a/config/server/caches/projects/flush"
   }
 ]
diff --git a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/GetMasterBranchRevision.json b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/GetMasterBranchRevision.json
index 86a3c28..4f6a104 100644
--- a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/GetMasterBranchRevision.json
+++ b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/GetMasterBranchRevision.json
@@ -1,5 +1,5 @@
 [
   {
-    "url": "HTTP_SCHEME://HOSTNAME:HTTP_PORT/a/projects/PROJECT/branches/master"
+    "url": "HTTP_SCHEME://HOSTNAME:HTTP_PORTCONTEXT_PATH/a/projects/PROJECT/branches/master"
   }
 ]
diff --git a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/GetProjectsCacheEntries.json b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/GetProjectsCacheEntries.json
index e4e2643..e77d83b 100644
--- a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/GetProjectsCacheEntries.json
+++ b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/GetProjectsCacheEntries.json
@@ -1,5 +1,5 @@
 [
   {
-    "url": "HTTP_SCHEME://HOSTNAME:HTTP_PORT/a/config/server/caches/projects"
+    "url": "HTTP_SCHEME://HOSTNAME:HTTP_PORTCONTEXT_PATH/a/config/server/caches/projects"
   }
 ]
diff --git a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/ListProjects.json b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/ListProjects.json
index f6350be..528ef3e 100644
--- a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/ListProjects.json
+++ b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/ListProjects.json
@@ -1,5 +1,5 @@
 [
   {
-    "url": "HTTP_SCHEME://HOSTNAME:HTTP_PORT/a/projects/"
+    "url": "HTTP_SCHEME://HOSTNAME:HTTP_PORTCONTEXT_PATH/a/projects/"
   }
 ]
diff --git a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/ReplayRecordsFromFeeder.json b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/ReplayRecordsFromFeeder.json
index 30f5f23..195ed09 100644
--- a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/ReplayRecordsFromFeeder.json
+++ b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/ReplayRecordsFromFeeder.json
@@ -1,10 +1,10 @@
 [
   {
-    "url": "ssh://admin@HOSTNAME:SSH_PORT/_PROJECT",
+    "url": "ssh://USERNAME@HOSTNAME:SSH_PORT/_PROJECT",
     "cmd": "clone"
   },
   {
-    "url": "HTTP_SCHEME://HOSTNAME:HTTP_PORT/_PROJECT",
+    "url": "HTTP_SCHEME://HOSTNAME:HTTP_PORTCONTEXT_PATH/_PROJECT",
     "cmd": "clone"
   }
 ]
diff --git a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/RestoreChange.json b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/RestoreChange.json
index 665cc4d..9d24b5b 100644
--- a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/RestoreChange.json
+++ b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/RestoreChange.json
@@ -1,6 +1,6 @@
 [
   {
-    "url": "HTTP_SCHEME://HOSTNAME:HTTP_PORT/a/changes/",
+    "url": "HTTP_SCHEME://HOSTNAME:HTTP_PORTCONTEXT_PATH/a/changes/",
     "number": "NUMBER"
   }
 ]
diff --git a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/SubmitChange.json b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/SubmitChange.json
index 301c65b..13d5802 100644
--- a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/SubmitChange.json
+++ b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/SubmitChange.json
@@ -1,5 +1,5 @@
 [
   {
-    "url": "HTTP_SCHEME://HOSTNAME:HTTP_PORT/a/changes/"
+    "url": "HTTP_SCHEME://HOSTNAME:HTTP_PORTCONTEXT_PATH/a/changes/"
   }
 ]
diff --git a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/SubmitChangeInBranch.json b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/SubmitChangeInBranch.json
index 301c65b..13d5802 100644
--- a/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/SubmitChangeInBranch.json
+++ b/e2e-tests/src/test/resources/data/com/google/gerrit/scenarios/SubmitChangeInBranch.json
@@ -1,5 +1,5 @@
 [
   {
-    "url": "HTTP_SCHEME://HOSTNAME:HTTP_PORT/a/changes/"
+    "url": "HTTP_SCHEME://HOSTNAME:HTTP_PORTCONTEXT_PATH/a/changes/"
   }
 ]
diff --git a/e2e-tests/src/test/scala/com/google/gerrit/scenarios/AbandonChange.scala b/e2e-tests/src/test/scala/com/google/gerrit/scenarios/AbandonChange.scala
index d387a3e..d8ebf7f 100644
--- a/e2e-tests/src/test/scala/com/google/gerrit/scenarios/AbandonChange.scala
+++ b/e2e-tests/src/test/scala/com/google/gerrit/scenarios/AbandonChange.scala
@@ -24,7 +24,6 @@
 
 class AbandonChange extends GerritSimulation {
   private val data: FeederBuilder = jsonFile(resource).convert(keys).circular
-  private val projectName = className
   private var numbersCopy: mutable.Queue[Int] = mutable.Queue[Int]()
   private var createChange: Option[CreateChange] = Some(new CreateChange(projectName))
 
diff --git a/e2e-tests/src/test/scala/com/google/gerrit/scenarios/CheckNewProjectReplica1.scala b/e2e-tests/src/test/scala/com/google/gerrit/scenarios/CheckNewProjectReplica1.scala
index ae4fa80..692d576 100644
--- a/e2e-tests/src/test/scala/com/google/gerrit/scenarios/CheckNewProjectReplica1.scala
+++ b/e2e-tests/src/test/scala/com/google/gerrit/scenarios/CheckNewProjectReplica1.scala
@@ -22,7 +22,6 @@
 
 class CheckNewProjectReplica1 extends GitSimulation {
   private val data: FeederBuilder = jsonFile(resource).convert(keys).queue
-  private val projectName = className
 
   private lazy val replicationDuration = replicationDelay + SecondsPerWeightUnit
 
@@ -30,7 +29,6 @@
 
   override def replaceOverride(in: String): String = {
     var next = replaceProperty("http_port1", 8081, in)
-    next = replaceKeyWith("_project", projectName, next)
     super.replaceOverride(next)
   }
 
diff --git a/e2e-tests/src/test/scala/com/google/gerrit/scenarios/CloneUsingBothProtocols.scala b/e2e-tests/src/test/scala/com/google/gerrit/scenarios/CloneUsingBothProtocols.scala
index c283861..d1d9c88 100644
--- a/e2e-tests/src/test/scala/com/google/gerrit/scenarios/CloneUsingBothProtocols.scala
+++ b/e2e-tests/src/test/scala/com/google/gerrit/scenarios/CloneUsingBothProtocols.scala
@@ -22,12 +22,8 @@
 
 class CloneUsingBothProtocols extends GitSimulation {
   private val data: FeederBuilder = jsonFile(resource).convert(keys).circular
-  private val projectName = className
   private val duration = 2 * numberOfUsers
 
-  override def replaceOverride(in: String): String = {
-    replaceKeyWith("_project", projectName, in)
-  }
 
   private val test: ScenarioBuilder = scenario(uniqueName)
       .feed(data)
diff --git a/e2e-tests/src/test/scala/com/google/gerrit/scenarios/FlushProjectsCache.scala b/e2e-tests/src/test/scala/com/google/gerrit/scenarios/FlushProjectsCache.scala
index 9fef2cf..a7bda3c 100644
--- a/e2e-tests/src/test/scala/com/google/gerrit/scenarios/FlushProjectsCache.scala
+++ b/e2e-tests/src/test/scala/com/google/gerrit/scenarios/FlushProjectsCache.scala
@@ -22,7 +22,6 @@
 
 class FlushProjectsCache extends CacheFlushSimulation {
   private val data: FeederBuilder = jsonFile(resource).convert(keys).queue
-  private val projectName = className
 
   override def relativeRuntimeWeight = 2
 
diff --git a/e2e-tests/src/test/scala/com/google/gerrit/scenarios/GerritSimulation.scala b/e2e-tests/src/test/scala/com/google/gerrit/scenarios/GerritSimulation.scala
index c199dd9..e26fc00 100644
--- a/e2e-tests/src/test/scala/com/google/gerrit/scenarios/GerritSimulation.scala
+++ b/e2e-tests/src/test/scala/com/google/gerrit/scenarios/GerritSimulation.scala
@@ -23,6 +23,7 @@
 class GerritSimulation extends Simulation {
   implicit val conf: GatlingGitConfiguration = GatlingGitConfiguration()
 
+  private val defaultHostname: String = "localhost"
   protected val numberKey: String = "number"
 
   private val packageName = getClass.getPackage.getName
@@ -42,7 +43,7 @@
   protected val SecondsPerWeightUnit = 2
   val maxExecutionTime: Int = (SecondsPerWeightUnit * relativeRuntimeWeight * powerFactor).toInt
   private var cumulativeWaitTime = 0
-
+  protected var projectName: String = className
   /**
    * How long a scenario step should wait before starting to execute.
    * This is also registering that step's resulting wait time, so that time
@@ -73,16 +74,23 @@
       replaceProperty("parent", "All-Projects", parent.toString)
     case ("project", project) =>
       var precedes = replaceKeyWith("_project", className, project.toString)
-      precedes = replaceOverride(precedes)
+      precedes = replaceProperty("project", getFullProjectName(projectName), precedes)
       replaceProperty("project", precedes)
     case ("url", url) =>
       var in = replaceOverride(url.toString)
-      in = replaceProperty("hostname", "localhost", in)
+      in = replaceProperty("replica_hostname", getProperty("hostname", defaultHostname), in)
+      in = replaceProperty("hostname", defaultHostname, in)
       in = replaceProperty("http_port", 8080, in)
       in = replaceProperty("http_scheme", "http", in)
+      in = replaceProperty("username", "admin", in)
+      in = replaceProperty("context_path", "", in)
       replaceProperty("ssh_port", 29418, in)
   }
 
+  protected def getFullProjectName(projectName: String): String = {
+    getProperty("project_prefix", "") + projectName
+  }
+
   private def replaceProperty(term: String, in: String): String = {
     replaceProperty(term, term, in)
   }
diff --git a/e2e-tests/src/test/scala/com/google/gerrit/scenarios/GitSimulation.scala b/e2e-tests/src/test/scala/com/google/gerrit/scenarios/GitSimulation.scala
index e2f13a4..5d5f5d5 100644
--- a/e2e-tests/src/test/scala/com/google/gerrit/scenarios/GitSimulation.scala
+++ b/e2e-tests/src/test/scala/com/google/gerrit/scenarios/GitSimulation.scala
@@ -15,6 +15,7 @@
 package com.google.gerrit.scenarios
 
 import java.io.{File, IOException}
+import java.net.URLEncoder
 
 import com.github.barbasa.gatling.git.GitRequestSession
 import com.github.barbasa.gatling.git.protocol.GitProtocol
@@ -29,6 +30,11 @@
   protected val gitRequest = new GitRequestBuilder(GitRequestSession("${cmd}", "${url}"))
   protected val gitProtocol: GitProtocol = GitProtocol()
 
+  override def replaceOverride(in: String): String = {
+    var next = replaceKeyWith("_project", URLEncoder.encode(getFullProjectName(projectName), "UTF-8"), in)
+    super.replaceOverride(next)
+  }
+
   after {
     Thread.sleep(5000)
     val path = conf.tmpBasePath
diff --git a/e2e-tests/src/test/scala/com/google/gerrit/scenarios/ProjectSimulation.scala b/e2e-tests/src/test/scala/com/google/gerrit/scenarios/ProjectSimulation.scala
index d6cb937..7d7bed7 100644
--- a/e2e-tests/src/test/scala/com/google/gerrit/scenarios/ProjectSimulation.scala
+++ b/e2e-tests/src/test/scala/com/google/gerrit/scenarios/ProjectSimulation.scala
@@ -14,10 +14,12 @@
 
 package com.google.gerrit.scenarios
 
+import java.net.URLEncoder
+
 class ProjectSimulation extends GerritSimulation {
-  protected var projectName: String = "defaultTestProject"
+  projectName = "defaultTestProject"
 
   override def replaceOverride(in: String): String = {
-    replaceProperty("project", projectName, in)
+    replaceProperty("project", URLEncoder.encode(getFullProjectName(projectName), "UTF-8"), in)
   }
 }
diff --git a/e2e-tests/src/test/scala/com/google/gerrit/scenarios/ReplayRecordsFromFeeder.scala b/e2e-tests/src/test/scala/com/google/gerrit/scenarios/ReplayRecordsFromFeeder.scala
index 0bd9e4a..c049f09 100644
--- a/e2e-tests/src/test/scala/com/google/gerrit/scenarios/ReplayRecordsFromFeeder.scala
+++ b/e2e-tests/src/test/scala/com/google/gerrit/scenarios/ReplayRecordsFromFeeder.scala
@@ -22,13 +22,9 @@
 
 class ReplayRecordsFromFeeder extends GitSimulation {
   private val data: FeederBuilder = jsonFile(resource).convert(keys).circular
-  private val projectName = className
 
   override def relativeRuntimeWeight = 30
 
-  override def replaceOverride(in: String): String = {
-    replaceKeyWith("_project", projectName, in)
-  }
 
   private val test: ScenarioBuilder = scenario(uniqueName)
       .repeat(10) {
diff --git a/e2e-tests/src/test/scala/com/google/gerrit/scenarios/RestoreChange.scala b/e2e-tests/src/test/scala/com/google/gerrit/scenarios/RestoreChange.scala
index 81096b0..756a239 100644
--- a/e2e-tests/src/test/scala/com/google/gerrit/scenarios/RestoreChange.scala
+++ b/e2e-tests/src/test/scala/com/google/gerrit/scenarios/RestoreChange.scala
@@ -24,7 +24,6 @@
 
 class RestoreChange extends GerritSimulation {
   private val data: FeederBuilder = jsonFile(resource).convert(keys).circular
-  private val projectName = className
   private var numbersCopy: mutable.Queue[Int] = mutable.Queue[Int]()
 
   override def relativeRuntimeWeight = 10
diff --git a/e2e-tests/src/test/scala/com/google/gerrit/scenarios/SubmitChange.scala b/e2e-tests/src/test/scala/com/google/gerrit/scenarios/SubmitChange.scala
index 20be28a..49f0c4b 100644
--- a/e2e-tests/src/test/scala/com/google/gerrit/scenarios/SubmitChange.scala
+++ b/e2e-tests/src/test/scala/com/google/gerrit/scenarios/SubmitChange.scala
@@ -23,7 +23,6 @@
 
 class SubmitChange extends GerritSimulation {
   private val data: FeederBuilder = jsonFile(resource).convert(keys).queue
-  private val projectName = className
   private var createChange = new CreateChange(projectName)
 
   override def relativeRuntimeWeight = 10
diff --git a/e2e-tests/src/test/scala/com/google/gerrit/scenarios/SubmitChangeInBranch.scala b/e2e-tests/src/test/scala/com/google/gerrit/scenarios/SubmitChangeInBranch.scala
index 9e1431b..ca618c3 100644
--- a/e2e-tests/src/test/scala/com/google/gerrit/scenarios/SubmitChangeInBranch.scala
+++ b/e2e-tests/src/test/scala/com/google/gerrit/scenarios/SubmitChangeInBranch.scala
@@ -25,7 +25,6 @@
 class SubmitChangeInBranch extends GerritSimulation {
   private val data: FeederBuilder = jsonFile(resource).convert(keys).circular
   private var changesCopy: mutable.Queue[Int] = mutable.Queue[Int]()
-  private val projectName = className
 
   override def relativeRuntimeWeight = 10
 
diff --git a/java/Main.java b/java/Main.java
index 11d8234..09c8c76 100644
--- a/java/Main.java
+++ b/java/Main.java
@@ -12,6 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+@SuppressWarnings("DefaultPackage")
 public final class Main {
   private static final String FLOGGER_BACKEND_PROPERTY = "flogger.backend_factory";
   private static final String FLOGGER_LOGGING_CONTEXT = "flogger.logging_context";
diff --git a/java/com/google/gerrit/acceptance/AbstractDaemonTest.java b/java/com/google/gerrit/acceptance/AbstractDaemonTest.java
index 3934a6a..903b709 100644
--- a/java/com/google/gerrit/acceptance/AbstractDaemonTest.java
+++ b/java/com/google/gerrit/acceptance/AbstractDaemonTest.java
@@ -26,6 +26,7 @@
 import static com.google.gerrit.entities.Patch.COMMIT_MSG;
 import static com.google.gerrit.entities.Patch.MERGE_LIST;
 import static com.google.gerrit.extensions.api.changes.SubmittedTogetherOption.NON_VISIBLE_CHANGES;
+import static com.google.gerrit.extensions.api.changes.SubmittedTogetherOption.TOPIC_CLOSURE;
 import static com.google.gerrit.server.group.SystemGroupBackend.ANONYMOUS_USERS;
 import static com.google.gerrit.server.group.SystemGroupBackend.REGISTERED_USERS;
 import static com.google.gerrit.server.project.ProjectCache.illegalState;
@@ -38,12 +39,15 @@
 
 import com.github.rholder.retry.BlockStrategy;
 import com.google.common.base.Strings;
+import com.google.common.base.Ticker;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
+import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Iterables;
 import com.google.common.collect.Lists;
 import com.google.common.jimfs.Jimfs;
 import com.google.common.primitives.Chars;
+import com.google.common.testing.FakeTicker;
 import com.google.gerrit.acceptance.AcceptanceTestRequestScope.Context;
 import com.google.gerrit.acceptance.PushOneCommit.Result;
 import com.google.gerrit.acceptance.testsuite.account.TestSshKeys;
@@ -78,6 +82,7 @@
 import com.google.gerrit.extensions.api.changes.ReviewInput;
 import com.google.gerrit.extensions.api.changes.RevisionApi;
 import com.google.gerrit.extensions.api.changes.SubmittedTogetherInfo;
+import com.google.gerrit.extensions.api.changes.SubmittedTogetherOption;
 import com.google.gerrit.extensions.api.projects.BranchApi;
 import com.google.gerrit.extensions.api.projects.BranchInfo;
 import com.google.gerrit.extensions.api.projects.BranchInput;
@@ -95,8 +100,6 @@
 import com.google.gerrit.extensions.restapi.BinaryResult;
 import com.google.gerrit.extensions.restapi.IdString;
 import com.google.gerrit.extensions.restapi.RestApiException;
-import com.google.gerrit.index.project.ProjectIndex;
-import com.google.gerrit.index.project.ProjectIndexCollection;
 import com.google.gerrit.json.OutputFormat;
 import com.google.gerrit.server.GerritPersonIdent;
 import com.google.gerrit.server.IdentifiedUser;
@@ -123,11 +126,7 @@
 import com.google.gerrit.server.git.GitRepositoryManager;
 import com.google.gerrit.server.git.meta.MetaDataUpdate;
 import com.google.gerrit.server.group.SystemGroupBackend;
-import com.google.gerrit.server.index.account.AccountIndex;
-import com.google.gerrit.server.index.account.AccountIndexCollection;
 import com.google.gerrit.server.index.account.AccountIndexer;
-import com.google.gerrit.server.index.change.ChangeIndex;
-import com.google.gerrit.server.index.change.ChangeIndexCollection;
 import com.google.gerrit.server.index.change.ChangeIndexer;
 import com.google.gerrit.server.notedb.AbstractChangeNotes;
 import com.google.gerrit.server.notedb.ChangeNoteUtil;
@@ -163,7 +162,6 @@
 import java.nio.file.FileSystems;
 import java.nio.file.Files;
 import java.nio.file.Path;
-import java.security.KeyPair;
 import java.sql.Timestamp;
 import java.time.Instant;
 import java.util.ArrayList;
@@ -290,6 +288,7 @@
   @Inject protected ChangeNotes.Factory notesFactory;
   @Inject protected BatchAbandon batchAbandon;
   @Inject protected TestSshKeys sshKeys;
+  @Inject protected TestTicker testTicker;
 
   protected EventRecorder eventRecorder;
   protected GerritServer server;
@@ -310,14 +309,11 @@
   protected BlockStrategy noSleepBlockStrategy = t -> {}; // Don't sleep in tests.
 
   @Inject private AbstractChangeNotes.Args changeNotesArgs;
-  @Inject private AccountIndexCollection accountIndexes;
   @Inject private AccountIndexer accountIndexer;
-  @Inject private ChangeIndexCollection changeIndexes;
   @Inject private EventRecorder.Factory eventRecorderFactory;
   @Inject private InProcessProtocol inProcessProtocol;
   @Inject private PluginGuiceEnvironment pluginGuiceEnvironment;
   @Inject private PluginUser.Factory pluginUserFactory;
-  @Inject private ProjectIndexCollection projectIndexes;
   @Inject private RequestScopeOperations requestScopeOperations;
   @Inject private SitePaths sitePaths;
   @Inject private ProjectOperations projectOperations;
@@ -579,8 +575,7 @@
         && SshMode.useSsh()
         && (adminSshSession == null || userSshSession == null)) {
       // Create Ssh sessions
-      KeyPair adminKeyPair = sshKeys.getKeyPair(admin);
-      SshSessionFactory.initSsh(adminKeyPair);
+      SshSessionFactory.initSsh();
       Context ctx = newRequestContext(user);
       atrScope.set(ctx);
       userSshSession = ctx.getSession();
@@ -655,7 +650,10 @@
   }
 
   protected Project.NameKey createProjectOverAPI(
-      String nameSuffix, Project.NameKey parent, boolean createEmptyCommit, SubmitType submitType)
+      String nameSuffix,
+      @Nullable Project.NameKey parent,
+      boolean createEmptyCommit,
+      @Nullable SubmitType submitType)
       throws RestApiException {
     ProjectInput in = new ProjectInput();
     in.name = name(nameSuffix);
@@ -702,6 +700,8 @@
     }
     SystemReader.setInstance(oldSystemReader);
     oldSystemReader = null;
+    // Set useDefaultTicker in afterTest, so the next beforeTest will use the default ticker
+    testTicker.useDefaultTicker();
   }
 
   protected void closeSsh() {
@@ -1063,87 +1063,6 @@
     };
   }
 
-  protected void disableChangeIndexWrites() {
-    for (ChangeIndex i : changeIndexes.getWriteIndexes()) {
-      if (!(i instanceof ReadOnlyChangeIndex)) {
-        changeIndexes.addWriteIndex(new ReadOnlyChangeIndex(i));
-      }
-    }
-  }
-
-  protected void enableChangeIndexWrites() {
-    for (ChangeIndex i : changeIndexes.getWriteIndexes()) {
-      if (i instanceof ReadOnlyChangeIndex) {
-        changeIndexes.addWriteIndex(((ReadOnlyChangeIndex) i).unwrap());
-      }
-    }
-  }
-
-  protected AutoCloseable disableChangeIndex() {
-    disableChangeIndexWrites();
-    ChangeIndex maybeDisabledSearchIndex = changeIndexes.getSearchIndex();
-    if (!(maybeDisabledSearchIndex instanceof DisabledChangeIndex)) {
-      changeIndexes.setSearchIndex(new DisabledChangeIndex(maybeDisabledSearchIndex), false);
-    }
-
-    return () -> {
-      enableChangeIndexWrites();
-      ChangeIndex maybeEnabledSearchIndex = changeIndexes.getSearchIndex();
-      if (maybeEnabledSearchIndex instanceof DisabledChangeIndex) {
-        changeIndexes.setSearchIndex(
-            ((DisabledChangeIndex) maybeEnabledSearchIndex).unwrap(), false);
-      }
-    };
-  }
-
-  protected AutoCloseable disableAccountIndex() {
-    AccountIndex maybeDisabledSearchIndex = accountIndexes.getSearchIndex();
-    if (!(maybeDisabledSearchIndex instanceof DisabledAccountIndex)) {
-      accountIndexes.setSearchIndex(new DisabledAccountIndex(maybeDisabledSearchIndex), false);
-    }
-
-    return () -> {
-      AccountIndex maybeEnabledSearchIndex = accountIndexes.getSearchIndex();
-      if (maybeEnabledSearchIndex instanceof DisabledAccountIndex) {
-        accountIndexes.setSearchIndex(
-            ((DisabledAccountIndex) maybeEnabledSearchIndex).unwrap(), false);
-      }
-    };
-  }
-
-  protected AutoCloseable disableProjectIndex() {
-    disableProjectIndexWrites();
-    ProjectIndex maybeDisabledSearchIndex = projectIndexes.getSearchIndex();
-    if (!(maybeDisabledSearchIndex instanceof DisabledProjectIndex)) {
-      projectIndexes.setSearchIndex(new DisabledProjectIndex(maybeDisabledSearchIndex), false);
-    }
-
-    return () -> {
-      enableProjectIndexWrites();
-      ProjectIndex maybeEnabledSearchIndex = projectIndexes.getSearchIndex();
-      if (maybeEnabledSearchIndex instanceof DisabledProjectIndex) {
-        projectIndexes.setSearchIndex(
-            ((DisabledProjectIndex) maybeEnabledSearchIndex).unwrap(), false);
-      }
-    };
-  }
-
-  protected void disableProjectIndexWrites() {
-    for (ProjectIndex i : projectIndexes.getWriteIndexes()) {
-      if (!(i instanceof DisabledProjectIndex)) {
-        projectIndexes.addWriteIndex(new DisabledProjectIndex(i));
-      }
-    }
-  }
-
-  protected void enableProjectIndexWrites() {
-    for (ProjectIndex i : projectIndexes.getWriteIndexes()) {
-      if (i instanceof DisabledProjectIndex) {
-        projectIndexes.addWriteIndex(((DisabledProjectIndex) i).unwrap());
-      }
-    }
-  }
-
   protected static Gson newGson() {
     return OutputFormat.JSON_COMPACT.newGson();
   }
@@ -1194,9 +1113,37 @@
   }
 
   protected void assertSubmittedTogether(String chId, String... expected) throws Exception {
-    List<ChangeInfo> actual = gApi.changes().id(chId).submittedTogether();
+    assertSubmittedTogether(chId, ImmutableSet.of(), expected);
+  }
+
+  protected void assertSubmittedTogetherWithTopicClosure(String chId, String... expected)
+      throws Exception {
+    assertSubmittedTogether(chId, ImmutableSet.of(TOPIC_CLOSURE), expected);
+  }
+
+  protected void assertSubmittedTogether(
+      String chId,
+      ImmutableSet<SubmittedTogetherOption> submittedTogetherOptions,
+      String... expected)
+      throws Exception {
+    // This does not include NON_VISIBILE_CHANGES
+    List<ChangeInfo> actual =
+        submittedTogetherOptions.isEmpty()
+            ? gApi.changes().id(chId).submittedTogether()
+            : gApi.changes()
+                .id(chId)
+                .submittedTogether(EnumSet.copyOf(submittedTogetherOptions))
+                .changes;
+
+    EnumSet<SubmittedTogetherOption> enumSetIncludingNonVisibleChanges =
+        submittedTogetherOptions.isEmpty()
+            ? EnumSet.of(NON_VISIBLE_CHANGES)
+            : EnumSet.copyOf(submittedTogetherOptions);
+    enumSetIncludingNonVisibleChanges.add(NON_VISIBLE_CHANGES);
+
+    // This includes NON_VISIBLE_CHANGES for comparison.
     SubmittedTogetherInfo info =
-        gApi.changes().id(chId).submittedTogether(EnumSet.of(NON_VISIBLE_CHANGES));
+        gApi.changes().id(chId).submittedTogether(enumSetIncludingNonVisibleChanges);
 
     assertThat(info.nonVisibleChanges).isEqualTo(0);
     assertThat(Iterables.transform(actual, i1 -> i1.changeId))
@@ -1250,10 +1197,10 @@
     assertThat(replyTo.getString()).contains(email);
   }
 
-  protected Map<BranchNameKey, ObjectId> fetchFromSubmitPreview(String changeId) throws Exception {
-    try (BinaryResult result = gApi.changes().id(changeId).current().submitPreview()) {
-      return fetchFromBundles(result);
-    }
+  protected void assertMailNotReplyTo(Message message, String email) throws Exception {
+    assertThat(message.headers()).containsKey("Reply-To");
+    StringEmailHeader replyTo = (StringEmailHeader) message.headers().get("Reply-To");
+    assertThat(replyTo.getString()).doesNotContain(email);
   }
 
   /**
@@ -1608,6 +1555,13 @@
     }
   }
 
+  protected void clearSubmitRequirements(Project.NameKey project) throws Exception {
+    try (ProjectConfigUpdate u = updateProject(project)) {
+      u.getConfig().clearSubmitRequirements();
+      u.save();
+    }
+  }
+
   protected void configLabel(String label, LabelFunction func) throws Exception {
     configLabel(label, func, ImmutableList.of());
   }
@@ -1763,4 +1717,32 @@
           moduleClass.getName());
     }
   }
+
+  /** {@link Ticker} implementation for mocking without restarting GerritServer */
+  public static class TestTicker extends Ticker {
+    Ticker actualTicker;
+
+    public TestTicker() {
+      useDefaultTicker();
+    }
+
+    /** Switches to system ticker */
+    public Ticker useDefaultTicker() {
+      this.actualTicker = Ticker.systemTicker();
+      return actualTicker;
+    }
+
+    /** Switches to {@link FakeTicker} */
+    public FakeTicker useFakeTicker() {
+      if (!(this.actualTicker instanceof FakeTicker)) {
+        this.actualTicker = new FakeTicker();
+      }
+      return (FakeTicker) actualTicker;
+    }
+
+    @Override
+    public long read() {
+      return actualTicker.read();
+    }
+  }
 }
diff --git a/java/com/google/gerrit/acceptance/AbstractNotificationTest.java b/java/com/google/gerrit/acceptance/AbstractNotificationTest.java
index 6c9a2b1..da033c1 100644
--- a/java/com/google/gerrit/acceptance/AbstractNotificationTest.java
+++ b/java/com/google/gerrit/acceptance/AbstractNotificationTest.java
@@ -98,6 +98,7 @@
 
   protected static class FakeEmailSenderSubject extends Subject {
     private final FakeEmailSender fakeEmailSender;
+    private String emailTitle;
     private Message message;
     private StagedUsers users;
     private Map<RecipientType, List<String>> recipients = new HashMap<>();
@@ -145,6 +146,10 @@
                     ? ((StringEmailHeader) header).getString()
                     : header));
       }
+      EmailHeader titleHeader = message.headers().get("Subject");
+      if (titleHeader instanceof StringEmailHeader) {
+        emailTitle = ((StringEmailHeader) titleHeader).getString();
+      }
 
       return this;
     }
@@ -190,6 +195,15 @@
       return rcpt(users.supportReviewersByEmail ? BCC : null, emails);
     }
 
+    public FakeEmailSenderSubject title(String expectedEmailTitle) {
+      if (!emailTitle.equals(expectedEmailTitle)) {
+        failWithoutActual(
+            fact("Expected email title", expectedEmailTitle),
+            fact("but actual title is", emailTitle));
+      }
+      return this;
+    }
+
     private FakeEmailSenderSubject rcpt(@Nullable RecipientType type, String[] emails) {
       for (String email : emails) {
         rcpt(type, email);
diff --git a/java/com/google/gerrit/acceptance/AcceptanceTestRequestScope.java b/java/com/google/gerrit/acceptance/AcceptanceTestRequestScope.java
index 50536d8..c4bf20c 100644
--- a/java/com/google/gerrit/acceptance/AcceptanceTestRequestScope.java
+++ b/java/com/google/gerrit/acceptance/AcceptanceTestRequestScope.java
@@ -162,7 +162,7 @@
       new Scope() {
         @Override
         public <T> Provider<T> scope(Key<T> key, Provider<T> creator) {
-          return new Provider<T>() {
+          return new Provider<>() {
             @Override
             public T get() {
               return requireContext().get(key, creator);
diff --git a/java/com/google/gerrit/acceptance/BUILD b/java/com/google/gerrit/acceptance/BUILD
index d03d0310c..633081e 100644
--- a/java/com/google/gerrit/acceptance/BUILD
+++ b/java/com/google/gerrit/acceptance/BUILD
@@ -39,11 +39,9 @@
     "//lib:gson",
     "//lib:guava-retrying",
     "//lib:jgit",
-    "//lib:jgit-ssh-jsch",
     "//lib:jgit-ssh-apache",
-    "//lib:jsch",
     "//lib/commons:compress",
-    "//lib/commons:lang",
+    "//lib/commons:lang3",
     "//lib/flogger:api",
     "//lib/guice",
     "//lib/guice:guice-assistedinject",
@@ -124,6 +122,7 @@
     "//lib/truth",
     "//lib/truth:truth-java8-extension",
     "//lib/greenmail",
+    "//lib:guava-testlib",
 ] + TEST_DEPS
 
 java_library(
diff --git a/java/com/google/gerrit/acceptance/ExtensionRegistry.java b/java/com/google/gerrit/acceptance/ExtensionRegistry.java
index 3844788..0acf3bc 100644
--- a/java/com/google/gerrit/acceptance/ExtensionRegistry.java
+++ b/java/com/google/gerrit/acceptance/ExtensionRegistry.java
@@ -14,6 +14,7 @@
 
 package com.google.gerrit.acceptance;
 
+import com.google.gerrit.entities.SubmitRequirement;
 import com.google.gerrit.extensions.api.changes.ActionVisitor;
 import com.google.gerrit.extensions.config.CapabilityDefinition;
 import com.google.gerrit.extensions.config.DownloadScheme;
@@ -22,6 +23,7 @@
 import com.google.gerrit.extensions.events.AccountIndexedListener;
 import com.google.gerrit.extensions.events.ChangeIndexedListener;
 import com.google.gerrit.extensions.events.CommentAddedListener;
+import com.google.gerrit.extensions.events.GitBatchRefUpdateListener;
 import com.google.gerrit.extensions.events.GitReferenceUpdatedListener;
 import com.google.gerrit.extensions.events.GroupIndexedListener;
 import com.google.gerrit.extensions.events.ProjectIndexedListener;
@@ -49,6 +51,8 @@
 import com.google.gerrit.server.git.validators.OnSubmitValidationListener;
 import com.google.gerrit.server.git.validators.RefOperationValidationListener;
 import com.google.gerrit.server.logging.PerformanceLogger;
+import com.google.gerrit.server.query.change.ChangeQueryBuilder.ChangeHasOperandFactory;
+import com.google.gerrit.server.query.change.ChangeQueryBuilder.ChangeIsOperandFactory;
 import com.google.gerrit.server.restapi.change.OnPostReview;
 import com.google.gerrit.server.rules.SubmitRule;
 import com.google.gerrit.server.validators.AccountActivationValidationListener;
@@ -71,6 +75,7 @@
   private final DynamicSet<PerformanceLogger> performanceLoggers;
   private final DynamicSet<ProjectCreationValidationListener> projectCreationValidationListeners;
   private final DynamicSet<SubmitRule> submitRules;
+  private final DynamicSet<SubmitRequirement> submitRequirements;
   private final DynamicSet<ChangeMessageModifier> changeMessageModifiers;
   private final DynamicSet<ChangeETagComputation> changeETagComputations;
   private final DynamicSet<ActionVisitor> actionVisitors;
@@ -78,6 +83,7 @@
   private final DynamicSet<RefOperationValidationListener> refOperationValidationListeners;
   private final DynamicSet<CommentAddedListener> commentAddedListeners;
   private final DynamicSet<GitReferenceUpdatedListener> refUpdatedListeners;
+  private final DynamicSet<GitBatchRefUpdateListener> batchRefUpdateListeners;
   private final DynamicSet<FileHistoryWebLink> fileHistoryWebLinks;
   private final DynamicSet<PatchSetWebLink> patchSetWebLinks;
   private final DynamicSet<ResolveConflictsWebLink> resolveConflictsWebLinks;
@@ -98,6 +104,9 @@
   private final DynamicSet<ReviewerAddedListener> reviewerAddedListeners;
   private final DynamicSet<ReviewerDeletedListener> reviewerDeletedListeners;
 
+  private final DynamicMap<ChangeHasOperandFactory> hasOperands;
+  private final DynamicMap<ChangeIsOperandFactory> isOperands;
+
   @Inject
   ExtensionRegistry(
       DynamicSet<AccountIndexedListener> accountIndexedListeners,
@@ -110,6 +119,7 @@
       DynamicSet<PerformanceLogger> performanceLoggers,
       DynamicSet<ProjectCreationValidationListener> projectCreationValidationListeners,
       DynamicSet<SubmitRule> submitRules,
+      DynamicSet<SubmitRequirement> submitRequirements,
       DynamicSet<ChangeMessageModifier> changeMessageModifiers,
       DynamicSet<ChangeETagComputation> changeETagComputations,
       DynamicSet<ActionVisitor> actionVisitors,
@@ -117,6 +127,7 @@
       DynamicSet<RefOperationValidationListener> refOperationValidationListeners,
       DynamicSet<CommentAddedListener> commentAddedListeners,
       DynamicSet<GitReferenceUpdatedListener> refUpdatedListeners,
+      DynamicSet<GitBatchRefUpdateListener> batchRefUpdateListeners,
       DynamicSet<FileHistoryWebLink> fileHistoryWebLinks,
       DynamicSet<PatchSetWebLink> patchSetWebLinks,
       DynamicSet<ResolveConflictsWebLink> resolveConflictsWebLinks,
@@ -134,7 +145,9 @@
       DynamicSet<PluginPushOption> pluginPushOption,
       DynamicSet<OnPostReview> onPostReviews,
       DynamicSet<ReviewerAddedListener> reviewerAddedListeners,
-      DynamicSet<ReviewerDeletedListener> reviewerDeletedListeners) {
+      DynamicSet<ReviewerDeletedListener> reviewerDeletedListeners,
+      DynamicMap<ChangeHasOperandFactory> hasOperands,
+      DynamicMap<ChangeIsOperandFactory> isOperands) {
     this.accountIndexedListeners = accountIndexedListeners;
     this.changeIndexedListeners = changeIndexedListeners;
     this.groupIndexedListeners = groupIndexedListeners;
@@ -145,6 +158,7 @@
     this.performanceLoggers = performanceLoggers;
     this.projectCreationValidationListeners = projectCreationValidationListeners;
     this.submitRules = submitRules;
+    this.submitRequirements = submitRequirements;
     this.changeMessageModifiers = changeMessageModifiers;
     this.changeETagComputations = changeETagComputations;
     this.actionVisitors = actionVisitors;
@@ -152,6 +166,7 @@
     this.refOperationValidationListeners = refOperationValidationListeners;
     this.commentAddedListeners = commentAddedListeners;
     this.refUpdatedListeners = refUpdatedListeners;
+    this.batchRefUpdateListeners = batchRefUpdateListeners;
     this.fileHistoryWebLinks = fileHistoryWebLinks;
     this.patchSetWebLinks = patchSetWebLinks;
     this.editWebLinks = editWebLinks;
@@ -170,6 +185,8 @@
     this.onPostReviews = onPostReviews;
     this.reviewerAddedListeners = reviewerAddedListeners;
     this.reviewerDeletedListeners = reviewerDeletedListeners;
+    this.hasOperands = hasOperands;
+    this.isOperands = isOperands;
   }
 
   public Registration newRegistration() {
@@ -220,6 +237,18 @@
       return add(submitRules, submitRule);
     }
 
+    public Registration add(SubmitRequirement submitRequirement) {
+      return add(submitRequirements, submitRequirement);
+    }
+
+    public Registration add(ChangeHasOperandFactory hasOperand, String exportName) {
+      return add(hasOperands, hasOperand, exportName);
+    }
+
+    public Registration add(ChangeIsOperandFactory isOperand, String exportName) {
+      return add(isOperands, isOperand, exportName);
+    }
+
     public Registration add(ChangeMessageModifier changeMessageModifier) {
       return add(changeMessageModifiers, changeMessageModifier);
     }
@@ -252,6 +281,10 @@
       return add(refUpdatedListeners, refUpdatedListener);
     }
 
+    public Registration add(GitBatchRefUpdateListener batchRefUpdateListener) {
+      return add(batchRefUpdateListeners, batchRefUpdateListener);
+    }
+
     public Registration add(FileHistoryWebLink fileHistoryWebLink) {
       return add(fileHistoryWebLinks, fileHistoryWebLink);
     }
diff --git a/java/com/google/gerrit/acceptance/GerritServer.java b/java/com/google/gerrit/acceptance/GerritServer.java
index f13f02e..a149f29 100644
--- a/java/com/google/gerrit/acceptance/GerritServer.java
+++ b/java/com/google/gerrit/acceptance/GerritServer.java
@@ -22,7 +22,9 @@
 import com.google.auto.value.AutoValue;
 import com.google.common.base.MoreObjects;
 import com.google.common.base.Strings;
+import com.google.common.base.Ticker;
 import com.google.common.collect.ImmutableList;
+import com.google.gerrit.acceptance.AbstractDaemonTest.TestTicker;
 import com.google.gerrit.acceptance.FakeGroupAuditService.FakeGroupAuditServiceModule;
 import com.google.gerrit.acceptance.ReindexGroupsAtStartup.ReindexGroupsAtStartupModule;
 import com.google.gerrit.acceptance.ReindexProjectsAtStartup.ReindexProjectsAtStartupModule;
@@ -76,6 +78,7 @@
 import com.google.inject.Module;
 import com.google.inject.Provides;
 import com.google.inject.Singleton;
+import com.google.inject.multibindings.OptionalBinder;
 import java.lang.annotation.Annotation;
 import java.lang.annotation.Retention;
 import java.lang.reflect.Field;
@@ -430,6 +433,23 @@
                 .to(GitObjectVisibilityChecker.class);
           }
         });
+    daemon.addAdditionalSysModuleForTesting(
+        new AbstractModule() {
+          @Override
+          protected void configure() {
+            super.configure();
+            // GerritServer isn't restarted between tests. TestTicker allows to replace actual
+            // Ticker in tests without restarting server and transparently for other code.
+            // Alternative option with Provider<Ticker> is less convinient, because it affects how
+            // gerrit code should be written - i.e. Ticker must not be stored in fields and must
+            // always be obtained from the provider.
+            TestTicker testTicker = new TestTicker();
+            OptionalBinder.newOptionalBinder(binder(), Ticker.class)
+                .setBinding()
+                .toInstance(testTicker);
+            bind(TestTicker.class).toInstance(testTicker);
+          }
+        });
 
     if (desc.memory()) {
       checkArgument(additionalArgs.length == 0, "cannot pass args to in-memory server");
diff --git a/java/com/google/gerrit/acceptance/GitClientVersion.java b/java/com/google/gerrit/acceptance/GitClientVersion.java
index 4c9a32d..2415781 100644
--- a/java/com/google/gerrit/acceptance/GitClientVersion.java
+++ b/java/com/google/gerrit/acceptance/GitClientVersion.java
@@ -16,6 +16,8 @@
 
 import static java.util.stream.Collectors.joining;
 
+import com.google.common.base.Splitter;
+import java.util.List;
 import java.util.stream.IntStream;
 
 /** Class to parse and represent version of git-core client */
@@ -38,11 +40,11 @@
    */
   public GitClientVersion(String version) {
     // "git version x.y.z", at Google "git version x.y.z.gXXXXXXXXXX-goog"
-    String parts[] = version.split(" ")[2].split("\\.");
-    int numParts = Math.min(parts.length, 3); // ignore Google-specific part of the version
+    List<String> parts = Splitter.on(".").splitToList(Splitter.on(" ").splitToList(version).get(2));
+    int numParts = Math.min(parts.size(), 3); // ignore Google-specific part of the version
     v = new int[numParts];
     for (int i = 0; i < numParts; i++) {
-      v[i] = Integer.valueOf(parts[i]);
+      v[i] = Integer.valueOf(parts.get(i));
     }
   }
 
diff --git a/java/com/google/gerrit/acceptance/InProcessProtocol.java b/java/com/google/gerrit/acceptance/InProcessProtocol.java
index 83c63f9..17ce595 100644
--- a/java/com/google/gerrit/acceptance/InProcessProtocol.java
+++ b/java/com/google/gerrit/acceptance/InProcessProtocol.java
@@ -100,7 +100,7 @@
       new Scope() {
         @Override
         public <T> Provider<T> scope(Key<T> key, Provider<T> creator) {
-          return new Provider<T>() {
+          return new Provider<>() {
             @Override
             public T get() {
               Context ctx = current.get();
@@ -235,9 +235,9 @@
 
       PermissionBackend.ForProject perm = permissionBackend.currentUser().project(req.project);
       try {
-        perm.check(ProjectPermission.RUN_UPLOAD_PACK);
-      } catch (AuthException e) {
-        throw new ServiceNotAuthorizedException(e.getMessage(), e);
+        if (!perm.test(ProjectPermission.RUN_UPLOAD_PACK)) {
+          throw new ServiceNotAuthorizedException("upload pack not permitted");
+        }
       } catch (PermissionBackendException e) {
         throw new RuntimeException(e);
       }
diff --git a/java/com/google/gerrit/acceptance/ReadOnlyChangeIndex.java b/java/com/google/gerrit/acceptance/ReadOnlyChangeIndex.java
deleted file mode 100644
index f7a0669..0000000
--- a/java/com/google/gerrit/acceptance/ReadOnlyChangeIndex.java
+++ /dev/null
@@ -1,77 +0,0 @@
-// Copyright (C) 2016 The Android Open Source Project
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package com.google.gerrit.acceptance;
-
-import com.google.gerrit.entities.Change;
-import com.google.gerrit.index.QueryOptions;
-import com.google.gerrit.index.Schema;
-import com.google.gerrit.index.query.DataSource;
-import com.google.gerrit.index.query.Predicate;
-import com.google.gerrit.index.query.QueryParseException;
-import com.google.gerrit.server.index.change.ChangeIndex;
-import com.google.gerrit.server.query.change.ChangeData;
-
-class ReadOnlyChangeIndex implements ChangeIndex {
-  private final ChangeIndex index;
-
-  ReadOnlyChangeIndex(ChangeIndex index) {
-    this.index = index;
-  }
-
-  ChangeIndex unwrap() {
-    return index;
-  }
-
-  @Override
-  public Schema<ChangeData> getSchema() {
-    return index.getSchema();
-  }
-
-  @Override
-  public void close() {
-    index.close();
-  }
-
-  @Override
-  public void insert(ChangeData obj) {
-    // do nothing
-  }
-
-  @Override
-  public void replace(ChangeData obj) {
-    // do nothing
-  }
-
-  @Override
-  public void delete(Change.Id key) {
-    // do nothing
-  }
-
-  @Override
-  public void deleteAll() {
-    // do nothing
-  }
-
-  @Override
-  public DataSource<ChangeData> getSource(Predicate<ChangeData> p, QueryOptions opts)
-      throws QueryParseException {
-    return index.getSource(p, opts);
-  }
-
-  @Override
-  public void markReady(boolean ready) {
-    // do nothing
-  }
-}
diff --git a/java/com/google/gerrit/acceptance/SshSessionJsch.java b/java/com/google/gerrit/acceptance/SshSessionJsch.java
deleted file mode 100644
index fa4d1d1..0000000
--- a/java/com/google/gerrit/acceptance/SshSessionJsch.java
+++ /dev/null
@@ -1,174 +0,0 @@
-// Copyright (C) 2021 The Android Open Source Project
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package com.google.gerrit.acceptance;
-
-import static java.nio.charset.StandardCharsets.US_ASCII;
-import static java.nio.charset.StandardCharsets.UTF_8;
-
-import com.google.gerrit.acceptance.testsuite.account.TestAccount;
-import com.google.gerrit.acceptance.testsuite.account.TestSshKeys;
-import com.jcraft.jsch.ChannelExec;
-import com.jcraft.jsch.JSch;
-import com.jcraft.jsch.JSchException;
-import com.jcraft.jsch.Session;
-import java.io.IOException;
-import java.io.InputStream;
-import java.io.InputStreamReader;
-import java.io.Reader;
-import java.io.StringWriter;
-import java.net.InetSocketAddress;
-import java.nio.charset.StandardCharsets;
-import java.security.GeneralSecurityException;
-import java.security.KeyPair;
-import java.security.KeyPairGenerator;
-import java.security.NoSuchAlgorithmException;
-import java.security.SecureRandom;
-import java.util.Properties;
-import java.util.Scanner;
-import org.bouncycastle.openssl.jcajce.JcaPEMWriter;
-import org.bouncycastle.openssl.jcajce.JcaPKCS8Generator;
-import org.bouncycastle.util.io.pem.PemObject;
-import org.eclipse.jgit.transport.SshSessionFactory;
-import org.eclipse.jgit.transport.ssh.jsch.JschConfigSessionFactory;
-import org.eclipse.jgit.transport.ssh.jsch.OpenSshConfig.Host;
-import org.eclipse.jgit.util.FS;
-
-public class SshSessionJsch extends SshSession {
-
-  private Session session;
-
-  public static void initClient(KeyPair keyPair) {
-    Properties config = new Properties();
-    config.put("StrictHostKeyChecking", "no");
-    JSch.setConfig(config);
-
-    // register a JschConfigSessionFactory that adds the private key as identity
-    // to the JSch instance of JGit so that SSH communication via JGit can
-    // succeed
-    SshSessionFactory.setInstance(
-        new JschConfigSessionFactory() {
-          @Override
-          protected void configure(Host hc, Session session) {
-            try {
-              JSch jsch = getJSch(hc, FS.DETECTED);
-              jsch.addIdentity(
-                  "KeyPair", privateKey(keyPair), TestSshKeys.publicKeyBlob(keyPair), null);
-            } catch (JSchException | GeneralSecurityException | IOException e) {
-              throw new RuntimeException(e);
-            }
-          }
-        });
-  }
-
-  public static KeyPairGenerator initKeyPairGenerator() throws NoSuchAlgorithmException {
-    KeyPairGenerator gen;
-    gen = KeyPairGenerator.getInstance("RSA");
-    gen.initialize(512, new SecureRandom());
-    return gen;
-  }
-
-  public SshSessionJsch(TestSshKeys sshKeys, InetSocketAddress addr, TestAccount account) {
-    super(sshKeys, addr, account);
-  }
-
-  @Override
-  public void open() throws Exception {
-    getJschSession();
-  }
-
-  @Override
-  public void close() {
-    if (session != null) {
-      session.disconnect();
-      session = null;
-    }
-  }
-
-  @SuppressWarnings("resource")
-  @Override
-  public String exec(String command) throws Exception {
-    ChannelExec channel = (ChannelExec) getJschSession().openChannel("exec");
-    try {
-      channel.setCommand(command);
-      InputStream in = channel.getInputStream();
-      InputStream err = channel.getErrStream();
-      channel.connect();
-
-      Scanner s = new Scanner(err, UTF_8.name()).useDelimiter("\\A");
-      error = s.hasNext() ? s.next() : null;
-
-      s = new Scanner(in, UTF_8.name()).useDelimiter("\\A");
-      return s.hasNext() ? s.next() : "";
-    } finally {
-      channel.disconnect();
-    }
-  }
-
-  @SuppressWarnings("resource")
-  @Override
-  public int execAndReturnStatus(String command) throws Exception {
-    ChannelExec channel = (ChannelExec) getJschSession().openChannel("exec");
-    try {
-      channel.setCommand(command);
-      InputStream err = channel.getErrStream();
-      channel.connect();
-
-      Scanner s = new Scanner(err, UTF_8.name()).useDelimiter("\\A");
-      error = s.hasNext() ? s.next() : null;
-      return channel.getExitStatus();
-    } finally {
-      channel.disconnect();
-    }
-  }
-
-  @Override
-  public Reader execAndReturnReader(String command) throws Exception {
-    ChannelExec channel = (ChannelExec) getJschSession().openChannel("exec");
-    channel.setCommand(command);
-    channel.connect();
-
-    return new InputStreamReader(channel.getInputStream(), StandardCharsets.UTF_8) {
-      @Override
-      public void close() throws IOException {
-        super.close();
-        channel.disconnect();
-      }
-    };
-  }
-
-  private Session getJschSession() throws Exception {
-    if (session == null) {
-      KeyPair keyPair = sshKeys.getKeyPair(account);
-      JSch jsch = new JSch();
-      jsch.addIdentity("KeyPair", privateKey(keyPair), TestSshKeys.publicKeyBlob(keyPair), null);
-      String username = getUsername();
-      session = jsch.getSession(username, addr.getAddress().getHostAddress(), addr.getPort());
-      session.setConfig("StrictHostKeyChecking", "no");
-      session.connect();
-    }
-    return session;
-  }
-
-  private static byte[] privateKey(KeyPair keyPair) throws IOException {
-    // unencrypted form of PKCS#8 file
-    JcaPKCS8Generator gen1 = new JcaPKCS8Generator(keyPair.getPrivate(), null);
-    PemObject obj1 = gen1.generate();
-    StringWriter sw1 = new StringWriter();
-    try (JcaPEMWriter pw = new JcaPEMWriter(sw1)) {
-      pw.writeObject(obj1);
-    }
-    return sw1.toString().getBytes(US_ASCII.name());
-  }
-}
diff --git a/java/com/google/gerrit/acceptance/SshSessionMina.java b/java/com/google/gerrit/acceptance/SshSessionMina.java
index 3b0ba3b..89096e4 100644
--- a/java/com/google/gerrit/acceptance/SshSessionMina.java
+++ b/java/com/google/gerrit/acceptance/SshSessionMina.java
@@ -16,6 +16,7 @@
 
 import static com.google.common.io.RecursiveDeleteOption.ALLOW_INSECURE;
 import static java.nio.charset.StandardCharsets.UTF_8;
+import static java.nio.file.Files.createTempDirectory;
 
 import com.google.common.io.CharSink;
 import com.google.common.io.Files;
@@ -140,7 +141,7 @@
                   + addr.getPort());
 
       // TODO(davido): Switch to memory only key resolving mode.
-      File userhome = Files.createTempDir();
+      File userhome = createTempDirectory("home-").toFile();
 
       FS fs = FS.DETECTED.setUserHome(userhome);
       File sshDir = new File(userhome, ".ssh");
@@ -168,6 +169,7 @@
                 MoreFiles.deleteRecursively(userhome.toPath(), ALLOW_INSECURE);
               } catch (IOException e) {
                 e.printStackTrace();
+                throw new RuntimeException("Failed to cleanup userhome", e);
               }
             });
       }
diff --git a/java/com/google/gerrit/acceptance/TestMetricMaker.java b/java/com/google/gerrit/acceptance/TestMetricMaker.java
index 2620f99..85c5b6d 100644
--- a/java/com/google/gerrit/acceptance/TestMetricMaker.java
+++ b/java/com/google/gerrit/acceptance/TestMetricMaker.java
@@ -18,9 +18,8 @@
 import com.google.gerrit.metrics.Description;
 import com.google.gerrit.metrics.DisabledMetricMaker;
 import com.google.inject.Singleton;
-import java.util.HashMap;
-import java.util.Map;
-import org.apache.commons.lang.mutable.MutableLong;
+import java.util.concurrent.ConcurrentHashMap;
+import org.apache.commons.lang3.mutable.MutableLong;
 
 /**
  * {@link com.google.gerrit.metrics.MetricMaker} to be bound in tests.
@@ -49,7 +48,7 @@
  */
 @Singleton
 public class TestMetricMaker extends DisabledMetricMaker {
-  private final Map<String, MutableLong> counts = new HashMap<>();
+  private final ConcurrentHashMap<String, MutableLong> counts = new ConcurrentHashMap<>();
 
   public long getCount(String counter0Name) {
     return get(counter0Name).longValue();
diff --git a/java/com/google/gerrit/acceptance/TestOnStoreSubmitRequirementResultModifier.java b/java/com/google/gerrit/acceptance/TestOnStoreSubmitRequirementResultModifier.java
new file mode 100644
index 0000000..0138ffa
--- /dev/null
+++ b/java/com/google/gerrit/acceptance/TestOnStoreSubmitRequirementResultModifier.java
@@ -0,0 +1,86 @@
+// Copyright (C) 2022 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.acceptance;
+
+import com.google.common.collect.ImmutableList;
+import com.google.gerrit.entities.SubmitRequirement;
+import com.google.gerrit.entities.SubmitRequirementExpressionResult;
+import com.google.gerrit.entities.SubmitRequirementResult;
+import com.google.gerrit.server.project.OnStoreSubmitRequirementResultModifier;
+import com.google.gerrit.server.query.change.ChangeData;
+import com.google.gerrit.server.update.ChangeContext;
+import java.util.Optional;
+
+/** Implementation of {@link OnStoreSubmitRequirementResultModifier} that is used in tests. */
+public class TestOnStoreSubmitRequirementResultModifier
+    implements OnStoreSubmitRequirementResultModifier {
+
+  private ModificationStrategy modificationStrategy = ModificationStrategy.KEEP;
+
+  private boolean hide = false;
+
+  /**
+   * The strategy, used by this modifier to transform {@link SubmitRequirementResult} on {@link
+   * OnStoreSubmitRequirementResultModifier#modifyResultOnStore} invocations.
+   */
+  public enum ModificationStrategy {
+    KEEP,
+    FAIL,
+    PASS,
+    OVERRIDE
+  }
+
+  public void setModificationStrategy(ModificationStrategy modificationStrategy) {
+    this.modificationStrategy = modificationStrategy;
+  }
+
+  public void hide(boolean hide) {
+    this.hide = hide;
+  }
+
+  @Override
+  public SubmitRequirementResult modifyResultOnStore(
+      SubmitRequirement submitRequirement,
+      SubmitRequirementResult result,
+      ChangeData cd,
+      ChangeContext ctx) {
+    if (modificationStrategy.equals(ModificationStrategy.KEEP)) {
+      return result;
+    }
+    SubmitRequirementResult.Builder srResultBuilder = result.toBuilder().hidden(Optional.of(hide));
+    if (modificationStrategy.equals(ModificationStrategy.OVERRIDE)) {
+      return srResultBuilder
+          .overrideExpressionResult(
+              Optional.of(
+                  SubmitRequirementExpressionResult.create(
+                      submitRequirement.submittabilityExpression(),
+                      SubmitRequirementExpressionResult.Status.PASS,
+                      ImmutableList.of(),
+                      ImmutableList.of(
+                          submitRequirement.submittabilityExpression().expressionString()))))
+          .build();
+    }
+    return srResultBuilder
+        .submittabilityExpressionResult(
+            SubmitRequirementExpressionResult.create(
+                submitRequirement.submittabilityExpression(),
+                modificationStrategy.equals(ModificationStrategy.FAIL)
+                    ? SubmitRequirementExpressionResult.Status.FAIL
+                    : SubmitRequirementExpressionResult.Status.PASS,
+                ImmutableList.of(),
+                ImmutableList.of(submitRequirement.submittabilityExpression().expressionString())))
+        .build();
+  }
+}
diff --git a/java/com/google/gerrit/acceptance/rest/PluginResource.java b/java/com/google/gerrit/acceptance/rest/PluginResource.java
index 745d4fa..56710b9 100644
--- a/java/com/google/gerrit/acceptance/rest/PluginResource.java
+++ b/java/com/google/gerrit/acceptance/rest/PluginResource.java
@@ -20,6 +20,5 @@
 
 public class PluginResource extends ConfigResource {
 
-  static final TypeLiteral<RestView<PluginResource>> PLUGIN_KIND =
-      new TypeLiteral<RestView<PluginResource>>() {};
+  static final TypeLiteral<RestView<PluginResource>> PLUGIN_KIND = new TypeLiteral<>() {};
 }
diff --git a/java/com/google/gerrit/acceptance/testsuite/change/ChangeOperationsImpl.java b/java/com/google/gerrit/acceptance/testsuite/change/ChangeOperationsImpl.java
index 3b15b57..580f10f 100644
--- a/java/com/google/gerrit/acceptance/testsuite/change/ChangeOperationsImpl.java
+++ b/java/com/google/gerrit/acceptance/testsuite/change/ChangeOperationsImpl.java
@@ -48,8 +48,8 @@
 import com.google.inject.Inject;
 import java.io.IOException;
 import java.sql.Timestamp;
+import java.time.Instant;
 import java.util.Arrays;
-import java.util.Date;
 import java.util.Objects;
 import java.util.Optional;
 import org.eclipse.jgit.errors.ConfigInvalidException;
@@ -138,7 +138,7 @@
     try (Repository repository = repositoryManager.openRepository(project);
         ObjectInserter objectInserter = repository.newObjectInserter();
         RevWalk revWalk = new RevWalk(objectInserter.newReader())) {
-      Timestamp now = TimeUtil.nowTs();
+      Instant now = TimeUtil.now();
       IdentifiedUser changeOwner = getChangeOwner(changeCreation);
       PersonIdent authorAndCommitter =
           changeOwner.newCommitterIdent(now, serverIdent.getTimeZone());
@@ -431,7 +431,7 @@
       try (Repository repository = repositoryManager.openRepository(project);
           ObjectInserter objectInserter = repository.newObjectInserter();
           RevWalk revWalk = new RevWalk(objectInserter.newReader())) {
-        Timestamp now = TimeUtil.nowTs();
+        Instant now = TimeUtil.now();
         ObjectId newPatchsetCommit =
             createPatchsetCommit(
                 repository, revWalk, objectInserter, changeNotes, patchsetCreation, now);
@@ -457,7 +457,7 @@
         ObjectInserter objectInserter,
         ChangeNotes changeNotes,
         TestPatchsetCreation patchsetCreation,
-        Timestamp now)
+        Instant now)
         throws IOException, BadRequestException {
       ObjectId oldPatchsetCommitId = changeNotes.getCurrentPatchSet().commitId();
       RevCommit oldPatchsetCommit = repository.parseCommit(oldPatchsetCommitId);
@@ -494,10 +494,13 @@
       return Optional.ofNullable(oldPatchsetCommit.getAuthorIdent()).orElse(serverIdent);
     }
 
-    private PersonIdent getCommitter(RevCommit oldPatchsetCommit, Timestamp now) {
+    // TODO(issue-15517): Fix the JdkObsolete issue with Date once JGit's PersonIdent class supports
+    // Instants
+    @SuppressWarnings("JdkObsolete")
+    private PersonIdent getCommitter(RevCommit oldPatchsetCommit, Instant now) {
       PersonIdent oldPatchsetCommitter =
           Optional.ofNullable(oldPatchsetCommit.getCommitterIdent()).orElse(serverIdent);
-      if (asSeconds(now) == asSeconds(oldPatchsetCommitter.getWhen())) {
+      if (asSeconds(now) == asSeconds(oldPatchsetCommitter.getWhen().toInstant())) {
         /* We need to ensure that the resulting commit SHA-1 is different from the old patchset.
          * In real situations, this automatically happens as two patchsets won't have exactly the
          * same commit timestamp even when the tree and commit message are the same. In tests,
@@ -505,13 +508,13 @@
          * We could of course require that tests must use TestTimeUtil#setClockStep but
          * that would be an unnecessary nuisance for test writers. Hence, go with a simple solution
          * here and simply add a second. */
-        now = Timestamp.from(now.toInstant().plusSeconds(1));
+        now = now.plusSeconds(1);
       }
-      return new PersonIdent(oldPatchsetCommitter, now);
+      return new PersonIdent(oldPatchsetCommitter, Timestamp.from(now));
     }
 
-    private long asSeconds(Date date) {
-      return date.getTime() / 1000;
+    private long asSeconds(Instant date) {
+      return date.getEpochSecond();
     }
 
     private ImmutableList<ObjectId> getParents(
diff --git a/java/com/google/gerrit/acceptance/testsuite/change/IndexOperations.java b/java/com/google/gerrit/acceptance/testsuite/change/IndexOperations.java
new file mode 100644
index 0000000..cba9b15
--- /dev/null
+++ b/java/com/google/gerrit/acceptance/testsuite/change/IndexOperations.java
@@ -0,0 +1,162 @@
+// Copyright (C) 2022 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.acceptance.testsuite.change;
+
+import com.google.gerrit.acceptance.DisabledAccountIndex;
+import com.google.gerrit.acceptance.DisabledChangeIndex;
+import com.google.gerrit.acceptance.DisabledProjectIndex;
+import com.google.gerrit.index.project.ProjectIndex;
+import com.google.gerrit.index.project.ProjectIndexCollection;
+import com.google.gerrit.server.index.account.AccountIndex;
+import com.google.gerrit.server.index.account.AccountIndexCollection;
+import com.google.gerrit.server.index.change.ChangeIndex;
+import com.google.gerrit.server.index.change.ChangeIndexCollection;
+import com.google.inject.Inject;
+
+/** Helpers to enable and disable reads/writes to secondary indices during testing. */
+public interface IndexOperations {
+  /**
+   * Disables reads from the secondary index that this instance is scoped to. Reads fail with {@code
+   * UnsupportedOperationException}.
+   */
+  AutoCloseable disableReads();
+
+  /**
+   * Disables writes to the secondary index that this instance is scoped to. Writes fail with {@code
+   * UnsupportedOperationException}.
+   */
+  AutoCloseable disableWrites();
+
+  /** Disables reads from and writes to the secondary index that this instance is scoped to. */
+  default AutoCloseable disableReadsAndWrites() {
+    AutoCloseable reads = disableReads();
+    AutoCloseable writes = disableWrites();
+    return () -> {
+      reads.close();
+      writes.close();
+    };
+  }
+
+  class Change implements IndexOperations {
+    @Inject private ChangeIndexCollection indices;
+
+    @Override
+    public AutoCloseable disableReads() {
+      ChangeIndex maybeDisabledSearchIndex = indices.getSearchIndex();
+      if (!(maybeDisabledSearchIndex instanceof DisabledChangeIndex)) {
+        indices.setSearchIndex(
+            new DisabledChangeIndex(maybeDisabledSearchIndex), /* closeOld */ false);
+      }
+
+      return () -> {
+        ChangeIndex maybeEnabledSearchIndex = indices.getSearchIndex();
+        if (maybeEnabledSearchIndex instanceof DisabledChangeIndex) {
+          indices.setSearchIndex(
+              ((DisabledChangeIndex) maybeEnabledSearchIndex).unwrap(), /* closeOld */ false);
+        }
+      };
+    }
+
+    @Override
+    public AutoCloseable disableWrites() {
+      for (ChangeIndex i : indices.getWriteIndexes()) {
+        if (!(i instanceof DisabledChangeIndex)) {
+          indices.addWriteIndex(new DisabledChangeIndex(i));
+        }
+      }
+      return () -> {
+        for (ChangeIndex i : indices.getWriteIndexes()) {
+          if (i instanceof DisabledChangeIndex) {
+            indices.addWriteIndex(((DisabledChangeIndex) i).unwrap());
+          }
+        }
+      };
+    }
+  }
+
+  class Account implements IndexOperations {
+    @Inject private AccountIndexCollection indices;
+
+    @Override
+    public AutoCloseable disableReads() {
+      AccountIndex maybeDisabledSearchIndex = indices.getSearchIndex();
+      if (!(maybeDisabledSearchIndex instanceof DisabledAccountIndex)) {
+        indices.setSearchIndex(
+            new DisabledAccountIndex(maybeDisabledSearchIndex), /* closeOld */ false);
+      }
+
+      return () -> {
+        AccountIndex maybeEnabledSearchIndex = indices.getSearchIndex();
+        if (maybeEnabledSearchIndex instanceof DisabledAccountIndex) {
+          indices.setSearchIndex(
+              ((DisabledAccountIndex) maybeEnabledSearchIndex).unwrap(), /* closeOld */ false);
+        }
+      };
+    }
+
+    @Override
+    public AutoCloseable disableWrites() {
+      for (AccountIndex i : indices.getWriteIndexes()) {
+        if (!(i instanceof DisabledAccountIndex)) {
+          indices.addWriteIndex(new DisabledAccountIndex(i));
+        }
+      }
+      return () -> {
+        for (AccountIndex i : indices.getWriteIndexes()) {
+          if (i instanceof DisabledAccountIndex) {
+            indices.addWriteIndex(((DisabledAccountIndex) i).unwrap());
+          }
+        }
+      };
+    }
+  }
+
+  class Project implements IndexOperations {
+    @Inject private ProjectIndexCollection indices;
+
+    @Override
+    public AutoCloseable disableReads() {
+      ProjectIndex maybeDisabledSearchIndex = indices.getSearchIndex();
+      if (!(maybeDisabledSearchIndex instanceof DisabledProjectIndex)) {
+        indices.setSearchIndex(
+            new DisabledProjectIndex(maybeDisabledSearchIndex), /* closeOld */ false);
+      }
+
+      return () -> {
+        ProjectIndex maybeEnabledSearchIndex = indices.getSearchIndex();
+        if (maybeEnabledSearchIndex instanceof DisabledProjectIndex) {
+          indices.setSearchIndex(
+              ((DisabledProjectIndex) maybeEnabledSearchIndex).unwrap(), /* closeOld */ false);
+        }
+      };
+    }
+
+    @Override
+    public AutoCloseable disableWrites() {
+      for (ProjectIndex i : indices.getWriteIndexes()) {
+        if (!(i instanceof DisabledProjectIndex)) {
+          indices.addWriteIndex(new DisabledProjectIndex(i));
+        }
+      }
+      return () -> {
+        for (ProjectIndex i : indices.getWriteIndexes()) {
+          if (i instanceof DisabledProjectIndex) {
+            indices.addWriteIndex(((DisabledProjectIndex) i).unwrap());
+          }
+        }
+      };
+    }
+  }
+}
diff --git a/java/com/google/gerrit/acceptance/testsuite/change/PerPatchsetOperationsImpl.java b/java/com/google/gerrit/acceptance/testsuite/change/PerPatchsetOperationsImpl.java
index eda6c7e..9b393ef 100644
--- a/java/com/google/gerrit/acceptance/testsuite/change/PerPatchsetOperationsImpl.java
+++ b/java/com/google/gerrit/acceptance/testsuite/change/PerPatchsetOperationsImpl.java
@@ -38,7 +38,7 @@
 import com.google.inject.Inject;
 import com.google.inject.assistedinject.Assisted;
 import java.io.IOException;
-import java.sql.Timestamp;
+import java.time.Instant;
 import org.eclipse.jgit.lib.ObjectInserter;
 import org.eclipse.jgit.lib.Repository;
 import org.eclipse.jgit.revwalk.RevWalk;
@@ -106,7 +106,7 @@
     try (Repository repository = repositoryManager.openRepository(project);
         ObjectInserter objectInserter = repository.newObjectInserter();
         RevWalk revWalk = new RevWalk(objectInserter.newReader())) {
-      Timestamp now = TimeUtil.nowTs();
+      Instant now = TimeUtil.now();
 
       IdentifiedUser author = getAuthor(commentCreation);
       CommentAdditionOp commentAdditionOp = new CommentAdditionOp(commentCreation);
@@ -165,8 +165,7 @@
       short side = commentCreation.side().orElse(CommentSide.PATCHSET_COMMIT).getNumericSide();
       Boolean unresolved = commentCreation.unresolved().orElse(null);
       String parentUuid = commentCreation.parentUuid().orElse(null);
-      Timestamp createdOn =
-          commentCreation.createdOn().map(Timestamp::from).orElse(context.getWhen());
+      Instant createdOn = commentCreation.createdOn().orElse(context.getWhen());
       HumanComment newComment =
           commentsUtil.newHumanComment(
               context.getNotes(),
@@ -202,7 +201,7 @@
     try (Repository repository = repositoryManager.openRepository(project);
         ObjectInserter objectInserter = repository.newObjectInserter();
         RevWalk revWalk = new RevWalk(objectInserter.newReader())) {
-      Timestamp now = TimeUtil.nowTs();
+      Instant now = TimeUtil.now();
 
       IdentifiedUser author = getAuthor(robotCommentCreation);
       RobotCommentAdditionOp robotCommentAdditionOp =
diff --git a/java/com/google/gerrit/acceptance/testsuite/group/TestGroup.java b/java/com/google/gerrit/acceptance/testsuite/group/TestGroup.java
index c885353..0b21e2c 100644
--- a/java/com/google/gerrit/acceptance/testsuite/group/TestGroup.java
+++ b/java/com/google/gerrit/acceptance/testsuite/group/TestGroup.java
@@ -18,7 +18,7 @@
 import com.google.common.collect.ImmutableSet;
 import com.google.gerrit.entities.Account;
 import com.google.gerrit.entities.AccountGroup;
-import java.sql.Timestamp;
+import java.time.Instant;
 import java.util.Optional;
 
 @AutoValue
@@ -40,7 +40,7 @@
 
   public abstract boolean visibleToAll();
 
-  public abstract Timestamp createdOn();
+  public abstract Instant createdOn();
 
   public abstract ImmutableSet<Account.Id> members();
 
@@ -67,7 +67,7 @@
 
     public abstract Builder visibleToAll(boolean visibleToAll);
 
-    public abstract Builder createdOn(Timestamp createdOn);
+    public abstract Builder createdOn(Instant createdOn);
 
     public abstract Builder members(ImmutableSet<Account.Id> members);
 
diff --git a/java/com/google/gerrit/acceptance/testsuite/project/BUILD b/java/com/google/gerrit/acceptance/testsuite/project/BUILD
index f9e2fb5..850a133 100644
--- a/java/com/google/gerrit/acceptance/testsuite/project/BUILD
+++ b/java/com/google/gerrit/acceptance/testsuite/project/BUILD
@@ -17,7 +17,7 @@
         "//lib:jgit-junit",
         "//lib/auto:auto-value",
         "//lib/auto:auto-value-annotations",
-        "//lib/commons:lang",
+        "//lib/commons:lang3",
         "//lib/guice",
     ],
 )
diff --git a/java/com/google/gerrit/acceptance/testsuite/project/ProjectOperationsImpl.java b/java/com/google/gerrit/acceptance/testsuite/project/ProjectOperationsImpl.java
index 18da4b3..deeb843 100644
--- a/java/com/google/gerrit/acceptance/testsuite/project/ProjectOperationsImpl.java
+++ b/java/com/google/gerrit/acceptance/testsuite/project/ProjectOperationsImpl.java
@@ -43,7 +43,7 @@
 import com.google.inject.Inject;
 import java.io.IOException;
 import java.util.ArrayList;
-import org.apache.commons.lang.RandomStringUtils;
+import org.apache.commons.lang3.RandomStringUtils;
 import org.eclipse.jgit.errors.ConfigInvalidException;
 import org.eclipse.jgit.junit.TestRepository;
 import org.eclipse.jgit.lib.Config;
diff --git a/java/com/google/gerrit/acceptance/testsuite/request/SshSessionFactory.java b/java/com/google/gerrit/acceptance/testsuite/request/SshSessionFactory.java
index d5dd28a..3442b6e 100644
--- a/java/com/google/gerrit/acceptance/testsuite/request/SshSessionFactory.java
+++ b/java/com/google/gerrit/acceptance/testsuite/request/SshSessionFactory.java
@@ -14,10 +14,7 @@
 
 package com.google.gerrit.acceptance.testsuite.request;
 
-import static com.google.gerrit.server.config.SshClientImplementation.getFromEnvironment;
-
 import com.google.gerrit.acceptance.SshSession;
-import com.google.gerrit.acceptance.SshSessionJsch;
 import com.google.gerrit.acceptance.SshSessionMina;
 import com.google.gerrit.acceptance.testsuite.account.TestAccount;
 import com.google.gerrit.acceptance.testsuite.account.TestSshKeys;
@@ -28,25 +25,16 @@
 public class SshSessionFactory {
   public static SshSession createSession(
       TestSshKeys testSshKeys, InetSocketAddress sshAddress, TestAccount testAccount) {
-    return getFromEnvironment().isMina()
-        ? new SshSessionMina(testSshKeys, sshAddress, testAccount)
-        : new SshSessionJsch(testSshKeys, sshAddress, testAccount);
+    return new SshSessionMina(testSshKeys, sshAddress, testAccount);
   }
 
-  public static void initSsh(KeyPair keyPair) {
-    if (getFromEnvironment().isMina()) {
-      SshSessionMina.initClient();
-    } else {
-      SshSessionJsch.initClient(keyPair);
-    }
+  public static void initSsh() {
+    SshSessionMina.initClient();
   }
 
   private SshSessionFactory() {}
 
   public static KeyPair genSshKey() throws GeneralSecurityException {
-    return (getFromEnvironment().isMina()
-            ? SshSessionMina.initKeyPairGenerator()
-            : SshSessionJsch.initKeyPairGenerator())
-        .generateKeyPair();
+    return SshSessionMina.initKeyPairGenerator().generateKeyPair();
   }
 }
diff --git a/java/com/google/gerrit/auth/ldap/LdapGroupBackend.java b/java/com/google/gerrit/auth/ldap/LdapGroupBackend.java
index 2947efd..c3870f4 100644
--- a/java/com/google/gerrit/auth/ldap/LdapGroupBackend.java
+++ b/java/com/google/gerrit/auth/ldap/LdapGroupBackend.java
@@ -125,7 +125,7 @@
 
     String groupDn = uuid.get().substring(LDAP_UUID.length());
     CurrentUser user = userProvider.get();
-    if (!(user.isIdentifiedUser()) || !membershipsOf(user.asIdentifiedUser()).contains(uuid)) {
+    if (!user.isIdentifiedUser() || !membershipsOf(user.asIdentifiedUser()).contains(uuid)) {
       try {
         if (!existsCache.get(groupDn)) {
           return null;
diff --git a/java/com/google/gerrit/auth/ldap/LdapRealm.java b/java/com/google/gerrit/auth/ldap/LdapRealm.java
index 9a9f309..7699799 100644
--- a/java/com/google/gerrit/auth/ldap/LdapRealm.java
+++ b/java/com/google/gerrit/auth/ldap/LdapRealm.java
@@ -199,7 +199,7 @@
       String configOption, String suppliedValue, boolean disabledByBackend) {
     if (disabledByBackend && !Strings.isNullOrEmpty(suppliedValue)) {
       String msg = String.format("LDAP backend doesn't support: ldap.%s", configOption);
-      logger.atSevere().log(msg);
+      logger.atSevere().log("%s", msg);
       throw new IllegalArgumentException(msg);
     }
   }
diff --git a/java/com/google/gerrit/common/IoUtil.java b/java/com/google/gerrit/common/IoUtil.java
index 37f6c2c..09a8993 100644
--- a/java/com/google/gerrit/common/IoUtil.java
+++ b/java/com/google/gerrit/common/IoUtil.java
@@ -32,16 +32,27 @@
 public final class IoUtil {
   public static void copyWithThread(InputStream src, OutputStream dst) {
     new Thread("IoUtil-Copy") {
+      // We cannot propagate the exception since this code is running in a background thread.
+      // Printing the stacktrace is the best we can do. Hence ignoring the exception after printing
+      // the stacktrace is OK and it's fine to suppress the warning for the CatchAndPrintStackTrace
+      // bug pattern here.
+      @SuppressWarnings("CatchAndPrintStackTrace")
       @Override
       public void run() {
         try {
+          copyIo();
+        } catch (IOException e) {
+          e.printStackTrace();
+        }
+      }
+
+      private void copyIo() throws IOException {
+        try {
           final byte[] buf = new byte[256];
           int n;
           while (0 < (n = src.read(buf))) {
             dst.write(buf, 0, n);
           }
-        } catch (IOException e) {
-          e.printStackTrace();
         } finally {
           try {
             src.close();
diff --git a/java/com/google/gerrit/common/RuntimeVersion.java b/java/com/google/gerrit/common/RuntimeVersion.java
new file mode 100644
index 0000000..9ab1b96
--- /dev/null
+++ b/java/com/google/gerrit/common/RuntimeVersion.java
@@ -0,0 +1,33 @@
+// Copyright (C) 2022 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.common;
+
+/** JDK version string utilities. */
+public final class RuntimeVersion {
+
+  private static final int FEATURE = Runtime.version().feature();
+
+  /** Returns true if the current runtime is JDK 17 or newer. */
+  public static boolean isAtLeast17() {
+    return FEATURE >= 17;
+  }
+
+  /** Returns true if the current runtime is JDK 18 or newer. */
+  public static boolean isAtLeast18() {
+    return FEATURE >= 18;
+  }
+
+  private RuntimeVersion() {}
+}
diff --git a/java/com/google/gerrit/common/Version.java b/java/com/google/gerrit/common/Version.java
index 6197be5..bfca4d0 100644
--- a/java/com/google/gerrit/common/Version.java
+++ b/java/com/google/gerrit/common/Version.java
@@ -54,7 +54,7 @@
         return vs;
       }
     } catch (IOException e) {
-      logger.atSevere().withCause(e).log(e.getMessage());
+      logger.atSevere().withCause(e).log("%s", e.getMessage());
       return "(unknown version)";
     }
   }
diff --git a/java/com/google/gerrit/common/data/FilenameComparator.java b/java/com/google/gerrit/common/data/FilenameComparator.java
index ebf423c..0b188df 100644
--- a/java/com/google/gerrit/common/data/FilenameComparator.java
+++ b/java/com/google/gerrit/common/data/FilenameComparator.java
@@ -24,7 +24,7 @@
   public static final FilenameComparator INSTANCE = new FilenameComparator();
 
   private static final Set<String> cppHeaderSuffixes =
-      new HashSet<>(Arrays.asList(".h", ".hxx", ".hpp"));
+      new HashSet<>(Arrays.asList(".h", ".hh", ".hxx", ".hpp"));
 
   private FilenameComparator() {}
 
diff --git a/java/com/google/gerrit/entities/Account.java b/java/com/google/gerrit/entities/Account.java
index cd3b27a..303e79f 100644
--- a/java/com/google/gerrit/entities/Account.java
+++ b/java/com/google/gerrit/entities/Account.java
@@ -22,7 +22,7 @@
 import com.google.common.primitives.Ints;
 import com.google.gerrit.common.Nullable;
 import com.google.gerrit.extensions.client.DiffPreferencesInfo;
-import java.sql.Timestamp;
+import java.time.Instant;
 import java.util.Optional;
 
 /**
@@ -123,7 +123,7 @@
   public abstract Id id();
 
   /** Date and time the user registered with the review server. */
-  public abstract Timestamp registeredOn();
+  public abstract Instant registeredOn();
 
   /** Full name of the user ("Given-name Surname" style). */
   @Nullable
@@ -157,7 +157,7 @@
    * @param newId unique id, see {@link com.google.gerrit.server.notedb.Sequences#nextAccountId()}.
    * @param registeredOn when the account was registered.
    */
-  public static Account.Builder builder(Account.Id newId, Timestamp registeredOn) {
+  public static Account.Builder builder(Account.Id newId, Instant registeredOn) {
     return new AutoValue_Account.Builder()
         .setInactive(false)
         .setId(newId)
@@ -196,9 +196,9 @@
    * <p>Example output:
    *
    * <ul>
-   *   <li>{@code A U. Thor &lt;author@example.com&gt;}: full populated
+   *   <li>{@code A U. Thor <author@example.com>}: full populated
    *   <li>{@code A U. Thor (12)}: missing email address
-   *   <li>{@code Anonymous Coward &lt;author@example.com&gt;}: missing name
+   *   <li>{@code Anonymous Coward <author@example.com>}: missing name
    *   <li>{@code Anonymous Coward (12)}: missing name and email address
    * </ul>
    */
@@ -230,9 +230,9 @@
 
     abstract Builder setId(Id id);
 
-    public abstract Timestamp registeredOn();
+    public abstract Instant registeredOn();
 
-    abstract Builder setRegisteredOn(Timestamp registeredOn);
+    abstract Builder setRegisteredOn(Instant registeredOn);
 
     @Nullable
     public abstract String fullName();
diff --git a/java/com/google/gerrit/entities/AccountGroupByIdAudit.java b/java/com/google/gerrit/entities/AccountGroupByIdAudit.java
index 17ddf51..0ef51e5 100644
--- a/java/com/google/gerrit/entities/AccountGroupByIdAudit.java
+++ b/java/com/google/gerrit/entities/AccountGroupByIdAudit.java
@@ -15,7 +15,7 @@
 package com.google.gerrit.entities;
 
 import com.google.auto.value.AutoValue;
-import java.sql.Timestamp;
+import java.time.Instant;
 import java.util.Optional;
 
 /** Inclusion of an {@link AccountGroup} in another {@link AccountGroup}. */
@@ -33,13 +33,13 @@
 
     public abstract Builder addedBy(Account.Id addedBy);
 
-    public abstract Builder addedOn(Timestamp addedOn);
+    public abstract Builder addedOn(Instant addedOn);
 
     abstract Builder removedBy(Account.Id removedBy);
 
-    abstract Builder removedOn(Timestamp removedOn);
+    abstract Builder removedOn(Instant removedOn);
 
-    public Builder removed(Account.Id removedBy, Timestamp removedOn) {
+    public Builder removed(Account.Id removedBy, Instant removedOn) {
       return removedBy(removedBy).removedOn(removedOn);
     }
 
@@ -52,11 +52,11 @@
 
   public abstract Account.Id addedBy();
 
-  public abstract Timestamp addedOn();
+  public abstract Instant addedOn();
 
   public abstract Optional<Account.Id> removedBy();
 
-  public abstract Optional<Timestamp> removedOn();
+  public abstract Optional<Instant> removedOn();
 
   public abstract Builder toBuilder();
 
diff --git a/java/com/google/gerrit/entities/AccountGroupMemberAudit.java b/java/com/google/gerrit/entities/AccountGroupMemberAudit.java
index 4d191b8..913956e 100644
--- a/java/com/google/gerrit/entities/AccountGroupMemberAudit.java
+++ b/java/com/google/gerrit/entities/AccountGroupMemberAudit.java
@@ -15,7 +15,7 @@
 package com.google.gerrit.entities;
 
 import com.google.auto.value.AutoValue;
-import java.sql.Timestamp;
+import java.time.Instant;
 import java.util.Optional;
 
 /** Membership of an {@link Account} in an {@link AccountGroup}. */
@@ -35,15 +35,15 @@
 
     abstract Account.Id addedBy();
 
-    public abstract Builder addedOn(Timestamp addedOn);
+    public abstract Builder addedOn(Instant addedOn);
 
-    abstract Timestamp addedOn();
+    abstract Instant addedOn();
 
     abstract Builder removedBy(Account.Id removedBy);
 
-    abstract Builder removedOn(Timestamp removedOn);
+    abstract Builder removedOn(Instant removedOn);
 
-    public Builder removed(Account.Id removedBy, Timestamp removedOn) {
+    public Builder removed(Account.Id removedBy, Instant removedOn) {
       return removedBy(removedBy).removedOn(removedOn);
     }
 
@@ -60,11 +60,11 @@
 
   public abstract Account.Id addedBy();
 
-  public abstract Timestamp addedOn();
+  public abstract Instant addedOn();
 
   public abstract Optional<Account.Id> removedBy();
 
-  public abstract Optional<Timestamp> removedOn();
+  public abstract Optional<Instant> removedOn();
 
   public abstract Builder toBuilder();
 
diff --git a/java/com/google/gerrit/entities/CachedProjectConfig.java b/java/com/google/gerrit/entities/CachedProjectConfig.java
index 76e35db..be4a1cf 100644
--- a/java/com/google/gerrit/entities/CachedProjectConfig.java
+++ b/java/com/google/gerrit/entities/CachedProjectConfig.java
@@ -227,7 +227,7 @@
       try {
         parsedProjectLevelConfigsBuilder().put(configFileName, ImmutableConfig.parse(config));
       } catch (ConfigInvalidException e) {
-        logger.atInfo().withCause(e).log("Config for " + configFileName + " not parsable");
+        logger.atInfo().withCause(e).log("Config for %s not parsable", configFileName);
       }
       return this;
     }
diff --git a/java/com/google/gerrit/entities/Change.java b/java/com/google/gerrit/entities/Change.java
index d1826bc..66e1a96 100644
--- a/java/com/google/gerrit/entities/Change.java
+++ b/java/com/google/gerrit/entities/Change.java
@@ -14,7 +14,6 @@
 
 package com.google.gerrit.entities;
 
-import static com.google.common.base.Preconditions.checkArgument;
 import static com.google.gerrit.entities.RefNames.REFS_CHANGES;
 
 import com.google.auto.value.AutoValue;
@@ -24,7 +23,7 @@
 import com.google.gson.Gson;
 import com.google.gson.TypeAdapter;
 import com.google.gson.annotations.SerializedName;
-import java.sql.Timestamp;
+import java.time.Instant;
 import java.util.Arrays;
 import java.util.Optional;
 
@@ -109,18 +108,6 @@
     /**
      * Parse a Change.Id out of a string representation.
      *
-     * @deprecated use {@link #tryParse(String)} instead.
-     */
-    @Deprecated
-    public static Id parse(String str) {
-      Integer id = Ints.tryParse(str);
-      checkArgument(id != null, "invalid change ID: %s", str);
-      return Change.id(id);
-    }
-
-    /**
-     * Parse a Change.Id out of a string representation.
-     *
      * @param str the string to parse
      * @return Optional containing the Change.Id, or {@code Optional.empty()} if str does not
      *     represent a valid Change.Id.
@@ -438,37 +425,37 @@
   }
 
   /** Locally assigned unique identifier of the change */
-  protected Id changeId;
+  private Id changeId;
 
   /** Globally assigned unique identifier of the change */
-  protected Key changeKey;
+  private Key changeKey;
 
   /** When this change was first introduced into the database. */
-  protected Timestamp createdOn;
+  private Instant createdOn;
 
   /**
    * When was a meaningful modification last made to this record's data
    *
    * <p>Note, this update timestamp includes its children.
    */
-  protected Timestamp lastUpdatedOn;
+  private Instant lastUpdatedOn;
 
-  protected Account.Id owner;
+  private Account.Id owner;
 
   /** The branch (and project) this change merges into. */
-  protected BranchNameKey dest;
+  private BranchNameKey dest;
 
   /** Current state code; see {@link Status}. */
-  protected char status;
+  private char status;
 
   /** The current patch set. */
-  protected int currentPatchSetId;
+  private int currentPatchSetId;
 
   /** Subject from the current patch set. */
-  protected String subject;
+  private String subject;
 
   /** Topic name assigned by the user, if any. */
-  @Nullable protected String topic;
+  @Nullable private String topic;
 
   /**
    * First line of first patch set's commit message.
@@ -476,40 +463,36 @@
    * <p>Unlike {@link #subject}, this string does not change if future patch sets change the first
    * line.
    */
-  @Nullable protected String originalSubject;
+  @Nullable private String originalSubject;
 
   /**
    * Unique id for the changes submitted together assigned during merging. Only set if the status is
    * MERGED.
    */
-  @Nullable protected String submissionId;
+  @Nullable private String submissionId;
 
   /** Allows assigning a change to a user. */
-  @Nullable protected Account.Id assignee;
+  @Nullable private Account.Id assignee;
 
   /** Whether the change is private. */
-  protected boolean isPrivate;
+  private boolean isPrivate;
 
   /** Whether the change is work in progress. */
-  protected boolean workInProgress;
+  private boolean workInProgress;
 
   /** Whether the change has started review. */
-  protected boolean reviewStarted;
+  private boolean reviewStarted;
 
   /** References a change that this change reverts. */
-  @Nullable protected Id revertOf;
+  @Nullable private Id revertOf;
 
   /** References the source change and patchset that this change was cherry-picked from. */
-  @Nullable protected PatchSet.Id cherryPickOf;
+  @Nullable private PatchSet.Id cherryPickOf;
 
-  protected Change() {}
+  Change() {}
 
   public Change(
-      Change.Key newKey,
-      Change.Id newId,
-      Account.Id ownedBy,
-      BranchNameKey forBranch,
-      Timestamp ts) {
+      Change.Key newKey, Change.Id newId, Account.Id ownedBy, BranchNameKey forBranch, Instant ts) {
     changeKey = newKey;
     changeId = newId;
     createdOn = ts;
@@ -567,19 +550,19 @@
     assignee = a;
   }
 
-  public Timestamp getCreatedOn() {
+  public Instant getCreatedOn() {
     return createdOn;
   }
 
-  public void setCreatedOn(Timestamp ts) {
+  public void setCreatedOn(Instant ts) {
     createdOn = ts;
   }
 
-  public Timestamp getLastUpdatedOn() {
+  public Instant getLastUpdatedOn() {
     return lastUpdatedOn;
   }
 
-  public void setLastUpdatedOn(Timestamp now) {
+  public void setLastUpdatedOn(Instant now) {
     lastUpdatedOn = now;
   }
 
diff --git a/java/com/google/gerrit/entities/ChangeMessage.java b/java/com/google/gerrit/entities/ChangeMessage.java
index cb56c31..609b54c 100644
--- a/java/com/google/gerrit/entities/ChangeMessage.java
+++ b/java/com/google/gerrit/entities/ChangeMessage.java
@@ -16,7 +16,7 @@
 
 import com.google.auto.value.AutoValue;
 import com.google.gerrit.common.Nullable;
-import java.sql.Timestamp;
+import java.time.Instant;
 import java.util.Objects;
 
 /**
@@ -40,40 +40,40 @@
     public abstract String uuid();
   }
 
-  protected Key key;
+  private Key key;
 
   /** Who wrote this comment; null if it was written by the Gerrit system. */
-  @Nullable protected Account.Id author;
+  @Nullable private Account.Id author;
 
   /** When this comment was drafted. */
-  protected Timestamp writtenOn;
+  private Instant writtenOn;
 
   /**
    * The text left by the user or Gerrit system in template form, that is free of Gerrit User
    * Identifiable Information and can be persisted in data storage.
    */
-  @Nullable protected String message;
+  @Nullable private String message;
 
   /** Which patchset (if any) was this message generated from? */
-  @Nullable protected PatchSet.Id patchset;
+  @Nullable private PatchSet.Id patchset;
 
   /** Tag associated with change message */
-  @Nullable protected String tag;
+  @Nullable private String tag;
 
   /** Real user that added this message on behalf of the user recorded in {@link #author}. */
-  @Nullable protected Account.Id realAuthor;
+  @Nullable private Account.Id realAuthor;
 
-  protected ChangeMessage() {}
+  private ChangeMessage() {}
 
   public static ChangeMessage create(
-      final ChangeMessage.Key k, @Nullable Account.Id a, Timestamp wo, @Nullable PatchSet.Id psid) {
+      final ChangeMessage.Key k, @Nullable Account.Id a, Instant wo, @Nullable PatchSet.Id psid) {
     return create(k, a, wo, psid, /*messageTemplate=*/ null, /*realAuthor=*/ null, /*tag=*/ null);
   }
 
   public static ChangeMessage create(
       final ChangeMessage.Key k,
       @Nullable Account.Id a,
-      Timestamp wo,
+      Instant wo,
       @Nullable PatchSet.Id psid,
       @Nullable String messageTemplate,
       @Nullable Account.Id realAuthor,
@@ -103,7 +103,7 @@
     return realAuthor != null ? realAuthor : getAuthor();
   }
 
-  public Timestamp getWrittenOn() {
+  public Instant getWrittenOn() {
     return writtenOn;
   }
 
diff --git a/java/com/google/gerrit/entities/ChangeSizeBucket.java b/java/com/google/gerrit/entities/ChangeSizeBucket.java
new file mode 100644
index 0000000..4d01ebd
--- /dev/null
+++ b/java/com/google/gerrit/entities/ChangeSizeBucket.java
@@ -0,0 +1,64 @@
+// Copyright (C) 2022 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+package com.google.gerrit.entities;
+
+/**
+ * A human-readable change size bucket.
+ *
+ * <p>Should be kept in sync with
+ * polygerrit-ui/app/elements/change-list/gr-change-list-item/gr-change-list-item.ts
+ */
+public class ChangeSizeBucket {
+
+  /**
+   * The upper bounds for the different size buckets.
+   *
+   * <p>Same as gr-change-list-item.ts::ChangeSize.
+   */
+  private enum BucketThresholds {
+    XS(10),
+    SMALL(50),
+    MEDIUM(250),
+    LARGE(1000);
+
+    public final long delta;
+
+    BucketThresholds(long delta) {
+      this.delta = delta;
+    }
+  }
+
+  /**
+   * Gets the correlative size bucket for the given change delta.
+   *
+   * <p>Same as gr-change-list-item.ts::computeChangeSize().
+   *
+   * @param delta the total number of changed lines (additions+deletions) of the change.
+   * @return a short human-readable size bucket.
+   */
+  public static String getChangeSizeBucket(long delta) {
+    if (delta == 0) {
+      return "NoOp";
+    } else if (delta < BucketThresholds.XS.delta) {
+      return "XS";
+    } else if (delta < BucketThresholds.SMALL.delta) {
+      return "S";
+    } else if (delta < BucketThresholds.MEDIUM.delta) {
+      return "M";
+    } else if (delta < BucketThresholds.LARGE.delta) {
+      return "L";
+    }
+    return "XL";
+  }
+}
diff --git a/java/com/google/gerrit/entities/Comment.java b/java/com/google/gerrit/entities/Comment.java
index 37b8620..65a1559 100644
--- a/java/com/google/gerrit/entities/Comment.java
+++ b/java/com/google/gerrit/entities/Comment.java
@@ -18,6 +18,7 @@
 import com.google.common.base.MoreObjects.ToStringHelper;
 import com.google.gerrit.common.Nullable;
 import java.sql.Timestamp;
+import java.time.Instant;
 import java.util.Comparator;
 import java.util.Objects;
 import org.eclipse.jgit.lib.AnyObjectId;
@@ -88,7 +89,7 @@
         Key k = (Key) o;
         return Objects.equals(uuid, k.uuid)
             && Objects.equals(filename, k.filename)
-            && Objects.equals(patchSetId, k.patchSetId);
+            && patchSetId == k.patchSetId;
       }
       return false;
     }
@@ -113,7 +114,7 @@
     @Override
     public boolean equals(Object o) {
       if (o instanceof Identity) {
-        return Objects.equals(id, ((Identity) o).id);
+        return id == ((Identity) o).id;
       }
       return false;
     }
@@ -180,10 +181,10 @@
     public boolean equals(Object o) {
       if (o instanceof Range) {
         Range r = (Range) o;
-        return Objects.equals(startLine, r.startLine)
-            && Objects.equals(startChar, r.startChar)
-            && Objects.equals(endLine, r.endLine)
-            && Objects.equals(endChar, r.endChar);
+        return startLine == r.startLine
+            && startChar == r.startChar
+            && endLine == r.endLine
+            && endChar == r.endChar;
       }
       return false;
     }
@@ -215,7 +216,10 @@
 
   public Identity author;
   protected Identity realAuthor;
+
+  // TODO(issue-15525): Migrate this field from Timestamp to Instant
   public Timestamp writtenOn;
+
   public short side;
   public String message;
   public String parentUuid;
@@ -233,13 +237,7 @@
   public String serverId;
 
   public Comment(Comment c) {
-    this(
-        new Key(c.key),
-        c.author.getId(),
-        new Timestamp(c.writtenOn.getTime()),
-        c.side,
-        c.message,
-        c.serverId);
+    this(new Key(c.key), c.author.getId(), c.writtenOn.toInstant(), c.side, c.message, c.serverId);
     this.lineNbr = c.lineNbr;
     this.realAuthor = c.realAuthor;
     this.parentUuid = c.parentUuid;
@@ -249,21 +247,20 @@
   }
 
   public Comment(
-      Key key,
-      Account.Id author,
-      Timestamp writtenOn,
-      short side,
-      String message,
-      String serverId) {
+      Key key, Account.Id author, Instant writtenOn, short side, String message, String serverId) {
     this.key = key;
     this.author = new Comment.Identity(author);
     this.realAuthor = this.author;
-    this.writtenOn = writtenOn;
+    this.writtenOn = Timestamp.from(writtenOn);
     this.side = side;
     this.message = message;
     this.serverId = serverId;
   }
 
+  public void setWrittenOn(Instant writtenOn) {
+    this.writtenOn = Timestamp.from(writtenOn);
+  }
+
   public void setLineNbrAndRange(
       Integer lineNbr, com.google.gerrit.extensions.client.Comment.Range range) {
     this.lineNbr = lineNbr != null ? lineNbr : range != null ? range.endLine : 0;
diff --git a/java/com/google/gerrit/entities/EmailHeader.java b/java/com/google/gerrit/entities/EmailHeader.java
index bf5a644..e43b6a3 100644
--- a/java/com/google/gerrit/entities/EmailHeader.java
+++ b/java/com/google/gerrit/entities/EmailHeader.java
@@ -19,7 +19,9 @@
 import com.google.common.base.MoreObjects;
 import java.io.IOException;
 import java.io.Writer;
-import java.text.SimpleDateFormat;
+import java.time.Instant;
+import java.time.ZoneId;
+import java.time.format.DateTimeFormatter;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
@@ -127,13 +129,13 @@
   }
 
   public static class Date extends EmailHeader {
-    private final java.util.Date value;
+    private final Instant value;
 
-    public Date(java.util.Date v) {
+    public Date(Instant v) {
       value = v;
     }
 
-    public java.util.Date getDate() {
+    public Instant getDate() {
       return value;
     }
 
@@ -144,10 +146,12 @@
 
     @Override
     public void write(Writer w) throws IOException {
-      final SimpleDateFormat fmt;
-      // Mon, 1 Jun 2009 10:49:44 -0700
-      fmt = new SimpleDateFormat("EEE, d MMM yyyy HH:mm:ss Z", Locale.US);
-      w.write(fmt.format(value));
+      // Mon, 1 Jun 2009 10:49:44 +0000
+      w.write(
+          DateTimeFormatter.ofPattern("EEE, d MMM yyyy HH:mm:ss Z")
+              .withLocale(Locale.US)
+              .withZone(ZoneId.of("UTC"))
+              .format(value));
     }
 
     @Override
diff --git a/java/com/google/gerrit/entities/GroupDescription.java b/java/com/google/gerrit/entities/GroupDescription.java
index 7054bed..666e8f6 100644
--- a/java/com/google/gerrit/entities/GroupDescription.java
+++ b/java/com/google/gerrit/entities/GroupDescription.java
@@ -15,7 +15,7 @@
 package com.google.gerrit.entities;
 
 import com.google.gerrit.common.Nullable;
-import java.sql.Timestamp;
+import java.time.Instant;
 import java.util.Set;
 
 /** Group methods exposed by the GroupBackend. */
@@ -55,7 +55,7 @@
 
     boolean isVisibleToAll();
 
-    Timestamp getCreatedOn();
+    Instant getCreatedOn();
 
     Set<Account.Id> getMembers();
 
diff --git a/java/com/google/gerrit/entities/HumanComment.java b/java/com/google/gerrit/entities/HumanComment.java
index 50bee8d..d287fa0 100644
--- a/java/com/google/gerrit/entities/HumanComment.java
+++ b/java/com/google/gerrit/entities/HumanComment.java
@@ -14,7 +14,7 @@
 
 package com.google.gerrit.entities;
 
-import java.sql.Timestamp;
+import java.time.Instant;
 import java.util.Objects;
 
 /**
@@ -33,7 +33,7 @@
   public HumanComment(
       Key key,
       Account.Id author,
-      Timestamp writtenOn,
+      Instant writtenOn,
       short side,
       String message,
       String serverId,
diff --git a/java/com/google/gerrit/entities/InternalGroup.java b/java/com/google/gerrit/entities/InternalGroup.java
index ebfa36a..43c3af3 100644
--- a/java/com/google/gerrit/entities/InternalGroup.java
+++ b/java/com/google/gerrit/entities/InternalGroup.java
@@ -18,7 +18,7 @@
 import com.google.common.collect.ImmutableSet;
 import com.google.gerrit.common.Nullable;
 import java.io.Serializable;
-import java.sql.Timestamp;
+import java.time.Instant;
 import org.eclipse.jgit.lib.ObjectId;
 
 @AutoValue
@@ -42,7 +42,7 @@
 
   public abstract AccountGroup.UUID getGroupUUID();
 
-  public abstract Timestamp getCreatedOn();
+  public abstract Instant getCreatedOn();
 
   public abstract ImmutableSet<Account.Id> getMembers();
 
@@ -71,7 +71,7 @@
 
     public abstract Builder setGroupUUID(AccountGroup.UUID groupUuid);
 
-    public abstract Builder setCreatedOn(Timestamp createdOn);
+    public abstract Builder setCreatedOn(Instant createdOn);
 
     public abstract Builder setMembers(ImmutableSet<Account.Id> members);
 
diff --git a/java/com/google/gerrit/entities/KeyUtil.java b/java/com/google/gerrit/entities/KeyUtil.java
index 40fb757..be28689 100644
--- a/java/com/google/gerrit/entities/KeyUtil.java
+++ b/java/com/google/gerrit/entities/KeyUtil.java
@@ -48,12 +48,12 @@
     for (char i = 'a'; i <= 'f'; i++) hexb[i] = (byte) ((i - 'a') + 10);
   }
 
-  public static String encode(final String e) {
+  public static String encode(final String key) {
     final byte[] b;
     try {
-      b = e.getBytes("UTF-8");
-    } catch (UnsupportedEncodingException e1) {
-      throw new RuntimeException("No UTF-8 support", e1);
+      b = key.getBytes("UTF-8");
+    } catch (UnsupportedEncodingException e) {
+      throw new IllegalStateException("No UTF-8 support", e);
     }
 
     final StringBuilder r = new StringBuilder(b.length);
@@ -71,20 +71,20 @@
     return r.toString();
   }
 
-  public static String decode(final String e) {
-    if (e.indexOf('%') < 0) {
-      return e.replace('+', ' ');
+  public static String decode(final String key) {
+    if (key.indexOf('%') < 0) {
+      return key.replace('+', ' ');
     }
 
-    final byte[] b = new byte[e.length()];
+    final byte[] b = new byte[key.length()];
     int bPtr = 0;
     try {
-      for (int i = 0; i < e.length(); ) {
-        final char c = e.charAt(i);
-        if (c == '%' && i + 2 < e.length()) {
-          final int v = (hexb[e.charAt(i + 1)] << 4) | hexb[e.charAt(i + 2)];
+      for (int i = 0; i < key.length(); ) {
+        final char c = key.charAt(i);
+        if (c == '%' && i + 2 < key.length()) {
+          final int v = (hexb[key.charAt(i + 1)] << 4) | hexb[key.charAt(i + 2)];
           if (v < 0) {
-            throw new IllegalArgumentException(e.substring(i, i + 3));
+            throw new IllegalArgumentException(key.substring(i, i + 3));
           }
           b[bPtr++] = (byte) v;
           i += 3;
@@ -97,12 +97,12 @@
         }
       }
     } catch (ArrayIndexOutOfBoundsException err) {
-      throw new IllegalArgumentException("Bad encoding" + e, err);
+      throw new IllegalArgumentException("Bad encoding" + key, err);
     }
     try {
       return new String(b, 0, bPtr, "UTF-8");
-    } catch (UnsupportedEncodingException e1) {
-      throw new RuntimeException("No UTF-8 support", e1);
+    } catch (UnsupportedEncodingException e) {
+      throw new IllegalStateException("No UTF-8 support", e);
     }
   }
 }
diff --git a/java/com/google/gerrit/entities/LabelType.java b/java/com/google/gerrit/entities/LabelType.java
index d254752..3541aac 100644
--- a/java/com/google/gerrit/entities/LabelType.java
+++ b/java/com/google/gerrit/entities/LabelType.java
@@ -95,6 +95,8 @@
 
   public abstract String getName();
 
+  public abstract Optional<String> getDescription();
+
   public abstract LabelFunction getFunction();
 
   public abstract boolean isCopyAnyScore();
@@ -141,8 +143,9 @@
   }
 
   public static LabelType.Builder builder(String name, List<LabelValue> valueList) {
-    return (new AutoValue_LabelType.Builder())
+    return new AutoValue_LabelType.Builder()
         .setName(name)
+        .setDescription(Optional.empty())
         .setValues(valueList)
         .setDefaultValue((short) 0)
         .setFunction(LabelFunction.MAX_WITH_BLOCK)
@@ -226,6 +229,8 @@
   public abstract static class Builder {
     public abstract Builder setName(String name);
 
+    public abstract Builder setDescription(Optional<String> description);
+
     public abstract Builder setFunction(LabelFunction function);
 
     public abstract Builder setCanOverride(boolean canOverride);
diff --git a/java/com/google/gerrit/entities/LabelTypes.java b/java/com/google/gerrit/entities/LabelTypes.java
index 55a9976..a2f2e0b 100644
--- a/java/com/google/gerrit/entities/LabelTypes.java
+++ b/java/com/google/gerrit/entities/LabelTypes.java
@@ -69,7 +69,7 @@
 
   public Comparator<String> nameComparator() {
     final Map<String, Integer> positions = positions();
-    return new Comparator<String>() {
+    return new Comparator<>() {
       @Override
       public int compare(String left, String right) {
         int lp = position(left);
diff --git a/java/com/google/gerrit/entities/PatchSet.java b/java/com/google/gerrit/entities/PatchSet.java
index b26e5c3..6c52368 100644
--- a/java/com/google/gerrit/entities/PatchSet.java
+++ b/java/com/google/gerrit/entities/PatchSet.java
@@ -22,7 +22,8 @@
 import com.google.common.base.Splitter;
 import com.google.common.collect.ImmutableList;
 import com.google.common.primitives.Ints;
-import java.sql.Timestamp;
+import com.google.errorprone.annotations.InlineMe;
+import java.time.Instant;
 import java.util.List;
 import java.util.Optional;
 import org.eclipse.jgit.lib.ObjectId;
@@ -41,6 +42,9 @@
    * @deprecated use isChangeRef instead.
    */
   @Deprecated
+  @InlineMe(
+      replacement = "PatchSet.isChangeRef(name)",
+      imports = "com.google.gerrit.entities.PatchSet")
   public static boolean isRef(String name) {
     return isChangeRef(name);
   }
@@ -159,7 +163,7 @@
 
     public abstract Builder uploader(Account.Id uploader);
 
-    public abstract Builder createdOn(Timestamp createdOn);
+    public abstract Builder createdOn(Instant createdOn);
 
     public abstract Builder groups(Iterable<String> groups);
 
@@ -206,7 +210,7 @@
    * Gerrit, and the old data erroneously did not include a {@code createdOn}, then this method will
    * return a timestamp of 0.
    */
-  public abstract Timestamp createdOn();
+  public abstract Instant createdOn();
 
   /**
    * Opaque group identifier, usually assigned during creation.
diff --git a/java/com/google/gerrit/entities/PatchSetApproval.java b/java/com/google/gerrit/entities/PatchSetApproval.java
index f853f77..608cf0d 100644
--- a/java/com/google/gerrit/entities/PatchSetApproval.java
+++ b/java/com/google/gerrit/entities/PatchSetApproval.java
@@ -16,8 +16,7 @@
 
 import com.google.auto.value.AutoValue;
 import com.google.common.primitives.Shorts;
-import java.sql.Timestamp;
-import java.util.Date;
+import java.time.Instant;
 import java.util.Optional;
 
 /** An approval (or negative approval) on a patch set. */
@@ -40,6 +39,36 @@
     }
   }
 
+  /**
+   * Globally unique identifier.
+   *
+   * <p>The identifier is unique to each granted approval, i.e. approvals, re-added within same
+   * {@link Change} or even {@link PatchSet} have different {@link UUID}.
+   */
+  @AutoValue
+  public abstract static class UUID implements Comparable<UUID> {
+
+    abstract String uuid();
+
+    public String get() {
+      return uuid();
+    }
+
+    @Override
+    public final int compareTo(UUID o) {
+      return uuid().compareTo(o.uuid());
+    }
+
+    @Override
+    public final String toString() {
+      return get();
+    }
+  }
+
+  public static UUID uuid(String n) {
+    return new AutoValue_PatchSetApproval_UUID(n);
+  }
+
   public static Builder builder() {
     return new AutoValue_PatchSetApproval.Builder().postSubmit(false).copied(false);
   }
@@ -50,17 +79,24 @@
 
     public abstract Key key();
 
+    /**
+     * {@link UUID} of {@link PatchSetApproval}.
+     *
+     * <p>Optional, since it might be missing for approvals, granted (persisted in NoteDB), before
+     * {@link UUID} was introduced and does not apply to removals ( represented as approval with
+     * {@link #value}, set to '0').
+     */
+    public abstract Builder uuid(Optional<UUID> uuid);
+
+    public abstract Builder uuid(UUID uuid);
+
     public abstract Builder value(short value);
 
     public Builder value(int value) {
       return value(Shorts.checkedCast(value));
     }
 
-    public abstract Builder granted(Timestamp granted);
-
-    public Builder granted(Date granted) {
-      return granted(new Timestamp(granted.getTime()));
-    }
+    public abstract Builder granted(Instant granted);
 
     public abstract Builder tag(String tag);
 
@@ -86,6 +122,8 @@
 
   public abstract Key key();
 
+  public abstract Optional<UUID> uuid();
+
   /**
    * Value assigned by the user.
    *
@@ -104,7 +142,7 @@
    */
   public abstract short value();
 
-  public abstract Timestamp granted();
+  public abstract Instant granted();
 
   public abstract Optional<String> tag();
 
@@ -117,8 +155,24 @@
 
   public abstract Builder toBuilder();
 
+  /**
+   * Makes a copy of {@link PatchSetApproval} that applies to {@code psId}.
+   *
+   * <p>The returned {@link PatchSetApproval} has the same {@link UUID} as the original {@link
+   * PatchSetApproval}, which is generated when it is originally granted.
+   *
+   * <p>This is needed since we want to keep the link between the original {@link PatchSetApproval}
+   * and the {@link #copied} one.
+   *
+   * @param psId {@link PatchSet.Id} of {@link PatchSet} that the copy should be applied to.
+   * @return {@link #copied} {@link PatchSetApproval} that applies to {@code psId}.
+   */
   public PatchSetApproval copyWithPatchSet(PatchSet.Id psId) {
-    return toBuilder().key(key(psId, key().accountId(), key().labelId())).copied(true).build();
+    return toBuilder()
+        .key(key(psId, key().accountId(), key().labelId()))
+        .uuid(uuid())
+        .copied(true)
+        .build();
   }
 
   public PatchSet.Id patchSetId() {
diff --git a/java/com/google/gerrit/entities/PatchSetInfo.java b/java/com/google/gerrit/entities/PatchSetInfo.java
index e3c6613..5770a7e 100644
--- a/java/com/google/gerrit/entities/PatchSetInfo.java
+++ b/java/com/google/gerrit/entities/PatchSetInfo.java
@@ -31,33 +31,33 @@
       this.shortMessage = requireNonNull(shortMessage);
     }
 
-    protected ParentInfo() {}
+    ParentInfo() {}
   }
 
-  protected PatchSet.Id key;
+  private PatchSet.Id key;
 
   /** First line of {@link #message}. */
-  protected String subject;
+  private String subject;
 
   /** The complete description of the change the patch set introduces. */
-  protected String message;
+  private String message;
 
   /** Identity of who wrote the patch set. May differ from {@link #committer}. */
-  protected UserIdentity author;
+  private UserIdentity author;
 
   /** Identity of who committed the patch set to the VCS. */
-  protected UserIdentity committer;
+  private UserIdentity committer;
 
   /** List of parents of the patch set. */
-  protected List<ParentInfo> parents;
+  private List<ParentInfo> parents;
 
   /** ID of commit. */
-  protected ObjectId commitId;
+  private ObjectId commitId;
 
   /** Optional user-supplied description for the patch set. */
-  protected String description;
+  private String description;
 
-  protected PatchSetInfo() {}
+  PatchSetInfo() {}
 
   public PatchSetInfo(PatchSet.Id k) {
     key = k;
diff --git a/java/com/google/gerrit/entities/RefNames.java b/java/com/google/gerrit/entities/RefNames.java
index 2263aba..b9c1b3c 100644
--- a/java/com/google/gerrit/entities/RefNames.java
+++ b/java/com/google/gerrit/entities/RefNames.java
@@ -14,8 +14,10 @@
 
 package com.google.gerrit.entities;
 
+import com.google.common.base.Splitter;
 import com.google.common.collect.ImmutableList;
 import com.google.gerrit.common.UsedAt;
+import java.util.List;
 
 /** Constants and utilities for Gerrit-specific ref names. */
 public class RefNames {
@@ -126,6 +128,8 @@
           REFS_STARRED_CHANGES,
           REFS_REJECT_COMMITS);
 
+  private static final Splitter SPLITTER = Splitter.on("/");
+
   public static String fullName(String ref) {
     return (ref.startsWith(REFS) || ref.equals(HEAD)) ? ref : REFS_HEADS + ref;
   }
@@ -344,16 +348,16 @@
       return null;
     }
 
-    String[] parts = name.split("/");
-    int n = parts.length;
+    List<String> parts = SPLITTER.splitToList(name);
+    int n = parts.size();
     if (n < 2) {
       return null;
     }
 
     // Last 2 digits.
     int le;
-    for (le = 0; le < parts[0].length(); le++) {
-      if (!Character.isDigit(parts[0].charAt(le))) {
+    for (le = 0; le < parts.get(0).length(); le++) {
+      if (!Character.isDigit(parts.get(0).charAt(le))) {
         return null;
       }
     }
@@ -363,8 +367,8 @@
 
     // Full ID.
     int ie;
-    for (ie = 0; ie < parts[1].length(); ie++) {
-      if (!Character.isDigit(parts[1].charAt(ie))) {
+    for (ie = 0; ie < parts.get(1).length(); ie++) {
+      if (!Character.isDigit(parts.get(1).charAt(ie))) {
         if (ie == 0) {
           return null;
         }
@@ -372,8 +376,8 @@
       }
     }
 
-    int shard = Integer.parseInt(parts[0]);
-    int id = Integer.parseInt(parts[1].substring(0, ie));
+    int shard = Integer.parseInt(parts.get(0));
+    int id = Integer.parseInt(parts.get(1).substring(0, ie));
 
     if (id % 100 != shard) {
       return null;
@@ -387,20 +391,20 @@
       return null;
     }
 
-    String[] parts = name.split("/");
-    int n = parts.length;
+    List<String> parts = SPLITTER.splitToList(name);
+    int n = parts.size();
     if (n != 2) {
       return null;
     }
 
     // First 2 chars.
-    if (parts[0].length() != 2) {
+    if (parts.get(0).length() != 2) {
       return null;
     }
 
     // Full UUID.
-    String uuid = parts[1];
-    if (!uuid.startsWith(parts[0])) {
+    String uuid = parts.get(1);
+    if (!uuid.startsWith(parts.get(0))) {
       return null;
     }
 
@@ -421,16 +425,16 @@
       return null;
     }
 
-    String[] parts = name.split("/");
-    int n = parts.length;
+    List<String> parts = SPLITTER.splitToList(name);
+    int n = parts.size();
     if (n < 2) {
       return null;
     }
 
     // Last 2 digits.
     int le;
-    for (le = 0; le < parts[0].length(); le++) {
-      if (!Character.isDigit(parts[0].charAt(le))) {
+    for (le = 0; le < parts.get(0).length(); le++) {
+      if (!Character.isDigit(parts.get(0).charAt(le))) {
         return null;
       }
     }
@@ -440,8 +444,8 @@
 
     // Full ID.
     int ie;
-    for (ie = 0; ie < parts[1].length(); ie++) {
-      if (!Character.isDigit(parts[1].charAt(ie))) {
+    for (ie = 0; ie < parts.get(1).length(); ie++) {
+      if (!Character.isDigit(parts.get(1).charAt(ie))) {
         if (ie == 0) {
           return null;
         }
@@ -449,8 +453,8 @@
       }
     }
 
-    int shard = Integer.parseInt(parts[0]);
-    int id = Integer.parseInt(parts[1].substring(0, ie));
+    int shard = Integer.parseInt(parts.get(0));
+    int id = Integer.parseInt(parts.get(1).substring(0, ie));
 
     if (id % 100 != shard) {
       return null;
@@ -489,7 +493,7 @@
     return Integer.parseInt(rest.substring(0, ie));
   }
 
-  static Integer parseRefSuffix(String name) {
+  public static Integer parseRefSuffix(String name) {
     if (name == null) {
       return null;
     }
diff --git a/java/com/google/gerrit/entities/RobotComment.java b/java/com/google/gerrit/entities/RobotComment.java
index e2e4114..1d46d3b 100644
--- a/java/com/google/gerrit/entities/RobotComment.java
+++ b/java/com/google/gerrit/entities/RobotComment.java
@@ -14,7 +14,7 @@
 
 package com.google.gerrit.entities;
 
-import java.sql.Timestamp;
+import java.time.Instant;
 import java.util.List;
 import java.util.Map;
 import java.util.Objects;
@@ -29,7 +29,7 @@
   public RobotComment(
       Key key,
       Account.Id author,
-      Timestamp writtenOn,
+      Instant writtenOn,
       short side,
       String message,
       String serverId,
diff --git a/java/com/google/gerrit/entities/StoredCommentLinkInfo.java b/java/com/google/gerrit/entities/StoredCommentLinkInfo.java
index f298782..dc5abbc 100644
--- a/java/com/google/gerrit/entities/StoredCommentLinkInfo.java
+++ b/java/com/google/gerrit/entities/StoredCommentLinkInfo.java
@@ -58,7 +58,7 @@
    * on it's own.
    */
   public static StoredCommentLinkInfo disabled(String name) {
-    return builder(name).setOverrideOnly(true).build();
+    return builder(name).setOverrideOnly(true).setEnabled(false).build();
   }
 
   /** Creates and returns a new {@link StoredCommentLinkInfo.Builder} instance. */
diff --git a/java/com/google/gerrit/entities/SubmitRecord.java b/java/com/google/gerrit/entities/SubmitRecord.java
index 95ad9f8..4142b42 100644
--- a/java/com/google/gerrit/entities/SubmitRecord.java
+++ b/java/com/google/gerrit/entities/SubmitRecord.java
@@ -70,7 +70,7 @@
 
   // Name of the rule that created this submit record, formatted as '$pluginName~$ruleName'
   public String ruleName;
-  public Status status;
+  public SubmitRecord.Status status;
   public List<Label> labels;
   public List<LegacySubmitRequirement> requirements;
   public String errorMessage;
@@ -113,7 +113,7 @@
     }
 
     public String label;
-    public Status status;
+    public Label.Status status;
     public Account.Id appliedBy;
 
     /**
diff --git a/java/com/google/gerrit/entities/SubmitRequirement.java b/java/com/google/gerrit/entities/SubmitRequirement.java
index 13e0b53..523b993 100644
--- a/java/com/google/gerrit/entities/SubmitRequirement.java
+++ b/java/com/google/gerrit/entities/SubmitRequirement.java
@@ -1,25 +1,37 @@
-//  Copyright (C) 2021 The Android Open Source Project
+// Copyright (C) 2021 The Android Open Source Project
 //
-//  Licensed under the Apache License, Version 2.0 (the "License");
-//  you may not use this file except in compliance with the License.
-//  You may obtain a copy of the License at
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
 //
-//  http://www.apache.org/licenses/LICENSE-2.0
+// http://www.apache.org/licenses/LICENSE-2.0
 //
-//  Unless required by applicable law or agreed to in writing, software
-//  distributed under the License is distributed on an "AS IS" BASIS,
-//  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-//  See the License for the specific language governing permissions and
-//  limitations under the License.
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
 
 package com.google.gerrit.entities;
 
 import com.google.auto.value.AutoValue;
+import com.google.gerrit.extensions.annotations.ExtensionPoint;
 import com.google.gson.Gson;
 import com.google.gson.TypeAdapter;
 import java.util.Optional;
 
-/** Entity describing a requirement that should be met for a change to become submittable. */
+/**
+ * Entity describing a requirement that should be met for a change to become submittable.
+ *
+ * <p>There are two ways to contribute {@link SubmitRequirement}:
+ *
+ * <ul>
+ *   <li>Set per-project in project.config (see {@link
+ *       com.google.gerrit.server.project.ProjectState#getSubmitRequirements()}
+ *   <li>Bind a global {@link SubmitRequirement} that will be evaluated for all projects.
+ * </ul>
+ */
+@ExtensionPoint
 @AutoValue
 public abstract class SubmitRequirement {
   /** Requirement name. */
@@ -32,7 +44,7 @@
    * Expression of the condition that makes the requirement applicable. The expression should be
    * evaluated for a specific {@link Change} and if it returns false, the requirement becomes
    * irrelevant for the change (i.e. {@link #submittabilityExpression()} and {@link
-   * #overrideExpression()} become irrelevant).
+   * #overrideExpression()} are not evaluated).
    *
    * <p>An empty {@link Optional} indicates that the requirement is applicable for any change.
    */
@@ -56,7 +68,12 @@
 
   /**
    * Boolean value indicating if the {@link SubmitRequirement} definition can be overridden in child
-   * projects. Default is false.
+   * projects.
+   *
+   * <p>For globally bound {@link SubmitRequirement}, indicates if can be overridden by {@link
+   * SubmitRequirement} in project.config.
+   *
+   * <p>Default is false.
    */
   public abstract boolean allowOverrideInChildProjects();
 
diff --git a/java/com/google/gerrit/entities/SubmitRequirementExpression.java b/java/com/google/gerrit/entities/SubmitRequirementExpression.java
index 2af1379..abac3e6 100644
--- a/java/com/google/gerrit/entities/SubmitRequirementExpression.java
+++ b/java/com/google/gerrit/entities/SubmitRequirementExpression.java
@@ -47,4 +47,12 @@
   public static TypeAdapter<SubmitRequirementExpression> typeAdapter(Gson gson) {
     return new AutoValue_SubmitRequirementExpression.GsonTypeAdapter(gson);
   }
+
+  /**
+   * Returns a "submit requirement" expression that requires the maximum vote on the Code-Review
+   * label.
+   */
+  public static SubmitRequirementExpression maxCodeReview() {
+    return SubmitRequirementExpression.create(String.format("label:Code-Review=MAX"));
+  }
 }
diff --git a/java/com/google/gerrit/entities/SubmitRequirementExpressionResult.java b/java/com/google/gerrit/entities/SubmitRequirementExpressionResult.java
index 900b2e2..aff0994 100644
--- a/java/com/google/gerrit/entities/SubmitRequirementExpressionResult.java
+++ b/java/com/google/gerrit/entities/SubmitRequirementExpressionResult.java
@@ -39,17 +39,17 @@
   /**
    * List leaf predicates that are fulfilled, for example the expression
    *
-   * <p><i>label:code-review=+2 and branch:refs/heads/master</i>
+   * <p><i>label:Code-Review=+2 and branch:refs/heads/master</i>
    *
    * <p>has two leaf predicates:
    *
    * <ul>
-   *   <li>label:code-review=+2
+   *   <li>label:Code-Review=+2
    *   <li>branch:refs/heads/master
    * </ul>
    *
    * This method will return the leaf predicates that were fulfilled, for example if only the first
-   * predicate was fulfilled, the returned list will be equal to ["label:code-review=+2"].
+   * predicate was fulfilled, the returned list will be equal to ["label:Code-Review=+2"].
    */
   public abstract ImmutableList<String> passingAtoms();
 
@@ -72,8 +72,17 @@
       Status status,
       ImmutableList<String> passingAtoms,
       ImmutableList<String> failingAtoms) {
+    return create(expression, status, passingAtoms, failingAtoms, Optional.empty());
+  }
+
+  public static SubmitRequirementExpressionResult create(
+      SubmitRequirementExpression expression,
+      Status status,
+      ImmutableList<String> passingAtoms,
+      ImmutableList<String> failingAtoms,
+      Optional<String> errorMessage) {
     return new AutoValue_SubmitRequirementExpressionResult(
-        expression, status, Optional.empty(), passingAtoms, failingAtoms);
+        expression, status, errorMessage, passingAtoms, failingAtoms);
   }
 
   public static SubmitRequirementExpressionResult error(
diff --git a/java/com/google/gerrit/entities/SubmitRequirementResult.java b/java/com/google/gerrit/entities/SubmitRequirementResult.java
index 13625c1..d9bb162 100644
--- a/java/com/google/gerrit/entities/SubmitRequirementResult.java
+++ b/java/com/google/gerrit/entities/SubmitRequirementResult.java
@@ -16,6 +16,7 @@
 
 import com.google.auto.value.AutoValue;
 import com.google.auto.value.extension.memoized.Memoized;
+import com.google.gerrit.common.Nullable;
 import com.google.gson.Gson;
 import com.google.gson.TypeAdapter;
 import java.util.Optional;
@@ -31,11 +32,18 @@
   public abstract Optional<SubmitRequirementExpressionResult> applicabilityExpressionResult();
 
   /**
-   * Result of evaluating a {@link SubmitRequirement#submittabilityExpression()} ()} on a change.
+   * Result of evaluating a {@link SubmitRequirement#submittabilityExpression()} on a change.
+   *
+   * <p>Empty if submit requirement does not apply.
    */
-  public abstract SubmitRequirementExpressionResult submittabilityExpressionResult();
+  public abstract Optional<SubmitRequirementExpressionResult> submittabilityExpressionResult();
 
-  /** Result of evaluating a {@link SubmitRequirement#overrideExpression()} ()} on a change. */
+  /**
+   * Result of evaluating a {@link SubmitRequirement#overrideExpression()} on a change.
+   *
+   * <p>Empty if submit requirement does not apply, or if the submit requirement did not define an
+   * override expression.
+   */
   public abstract Optional<SubmitRequirementExpressionResult> overrideExpressionResult();
 
   /** SHA-1 of the patchset commit ID for which the submit requirement was evaluated. */
@@ -53,9 +61,56 @@
     return legacy().orElse(false);
   }
 
+  /**
+   * Boolean indicating if the "submit requirement" was bypassed during submission, e.g. by
+   * performing a push with the %submit option.
+   */
+  public abstract Optional<Boolean> forced();
+
+  /**
+   * Whether this result should be filtered out when returned from REST API.
+   *
+   * <p>This can be used by {@link
+   * com.google.gerrit.server.project.OnStoreSubmitRequirementResultModifier}. It can override the
+   * {@code SubmitRequirementResult} status and might want to hide the SR from the API as if it was
+   * non-applicable (non-applicable SRs are currently hidden on UI).
+   */
+  public abstract Optional<Boolean> hidden();
+
+  public boolean isHidden() {
+    return hidden().orElse(false);
+  }
+
+  public Optional<String> errorMessage() {
+    if (!status().equals(Status.ERROR)) {
+      return Optional.empty();
+    }
+    if (applicabilityExpressionResult().isPresent()
+        && applicabilityExpressionResult().get().errorMessage().isPresent()) {
+      return Optional.of(
+          "Applicability expression result has an error: "
+              + applicabilityExpressionResult().get().errorMessage().get());
+    }
+    if (submittabilityExpressionResult().isPresent()
+        && submittabilityExpressionResult().get().errorMessage().isPresent()) {
+      return Optional.of(
+          "Submittability expression result has an error: "
+              + submittabilityExpressionResult().get().errorMessage().get());
+    }
+    if (overrideExpressionResult().isPresent()
+        && overrideExpressionResult().get().errorMessage().isPresent()) {
+      return Optional.of(
+          "Override expression result has an error: "
+              + overrideExpressionResult().get().errorMessage().get());
+    }
+    return Optional.of("No error logged.");
+  }
+
   @Memoized
   public Status status() {
-    if (assertError(submittabilityExpressionResult())
+    if (forced().orElse(false)) {
+      return Status.FORCED;
+    } else if (assertError(submittabilityExpressionResult())
         || assertError(applicabilityExpressionResult())
         || assertError(overrideExpressionResult())) {
       return Status.ERROR;
@@ -74,13 +129,18 @@
   @Memoized
   public boolean fulfilled() {
     Status s = status();
-    return s == Status.SATISFIED || s == Status.OVERRIDDEN || s == Status.NOT_APPLICABLE;
+    return s == Status.SATISFIED
+        || s == Status.OVERRIDDEN
+        || s == Status.NOT_APPLICABLE
+        || s == Status.FORCED;
   }
 
   public static Builder builder() {
     return new AutoValue_SubmitRequirementResult.Builder();
   }
 
+  public abstract Builder toBuilder();
+
   public static TypeAdapter<SubmitRequirementResult> typeAdapter(Gson gson) {
     return new AutoValue_SubmitRequirementResult.GsonTypeAdapter(gson);
   }
@@ -108,10 +168,16 @@
     NOT_APPLICABLE,
 
     /**
-     * Any of the applicability, blocking or override expressions contain invalid syntax and are not
-     * parsable.
+     * Any of the applicability, submittability or override expressions contain invalid syntax and
+     * are not parsable.
      */
-    ERROR
+    ERROR,
+
+    /**
+     * The "submit requirement" was bypassed during submission, e.g. by pushing for review with the
+     * %submit option.
+     */
+    FORCED
   }
 
   @AutoValue.Builder
@@ -121,7 +187,11 @@
     public abstract Builder applicabilityExpressionResult(
         Optional<SubmitRequirementExpressionResult> value);
 
-    public abstract Builder submittabilityExpressionResult(SubmitRequirementExpressionResult value);
+    public abstract Builder submittabilityExpressionResult(
+        Optional<SubmitRequirementExpressionResult> value);
+
+    public abstract Builder submittabilityExpressionResult(
+        @Nullable SubmitRequirementExpressionResult value);
 
     public abstract Builder overrideExpressionResult(
         Optional<SubmitRequirementExpressionResult> value);
@@ -130,36 +200,32 @@
 
     public abstract Builder legacy(Optional<Boolean> value);
 
+    public abstract Builder forced(Optional<Boolean> value);
+
+    public abstract Builder hidden(Optional<Boolean> value);
+
     public abstract SubmitRequirementResult build();
   }
 
-  private boolean assertPass(Optional<SubmitRequirementExpressionResult> expressionResult) {
+  public static boolean assertPass(Optional<SubmitRequirementExpressionResult> expressionResult) {
     return assertStatus(expressionResult, SubmitRequirementExpressionResult.Status.PASS);
   }
 
-  private boolean assertPass(SubmitRequirementExpressionResult expressionResult) {
-    return assertStatus(expressionResult, SubmitRequirementExpressionResult.Status.PASS);
-  }
-
-  private boolean assertFail(Optional<SubmitRequirementExpressionResult> expressionResult) {
+  public static boolean assertFail(Optional<SubmitRequirementExpressionResult> expressionResult) {
     return assertStatus(expressionResult, SubmitRequirementExpressionResult.Status.FAIL);
   }
 
-  private boolean assertError(Optional<SubmitRequirementExpressionResult> expressionResult) {
+  public static boolean assertError(Optional<SubmitRequirementExpressionResult> expressionResult) {
     return assertStatus(expressionResult, SubmitRequirementExpressionResult.Status.ERROR);
   }
 
-  private boolean assertError(SubmitRequirementExpressionResult expressionResult) {
-    return assertStatus(expressionResult, SubmitRequirementExpressionResult.Status.ERROR);
-  }
-
-  private boolean assertStatus(
+  private static boolean assertStatus(
       SubmitRequirementExpressionResult expressionResult,
       SubmitRequirementExpressionResult.Status status) {
     return expressionResult.status() == status;
   }
 
-  private boolean assertStatus(
+  private static boolean assertStatus(
       Optional<SubmitRequirementExpressionResult> expressionResult,
       SubmitRequirementExpressionResult.Status status) {
     return expressionResult.isPresent() && assertStatus(expressionResult.get(), status);
diff --git a/java/com/google/gerrit/entities/SubmoduleSubscription.java b/java/com/google/gerrit/entities/SubmoduleSubscription.java
index 5ea1b1e..db26eb3 100644
--- a/java/com/google/gerrit/entities/SubmoduleSubscription.java
+++ b/java/com/google/gerrit/entities/SubmoduleSubscription.java
@@ -25,11 +25,11 @@
  * <p>A subscriber operates a submodule in defined path.
  */
 public final class SubmoduleSubscription {
-  protected BranchNameKey superProject;
+  private BranchNameKey superProject;
 
-  protected String submodulePath;
+  private String submodulePath;
 
-  protected BranchNameKey submodule;
+  private BranchNameKey submodule;
 
   public SubmoduleSubscription(BranchNameKey superProject, BranchNameKey submodule, String path) {
     this.superProject = superProject;
diff --git a/java/com/google/gerrit/entities/UserIdentity.java b/java/com/google/gerrit/entities/UserIdentity.java
index e07d21a..8334157 100644
--- a/java/com/google/gerrit/entities/UserIdentity.java
+++ b/java/com/google/gerrit/entities/UserIdentity.java
@@ -14,26 +14,26 @@
 
 package com.google.gerrit.entities;
 
-import java.sql.Timestamp;
+import java.time.Instant;
 
 public final class UserIdentity {
   /** Full name of the user. */
-  protected String name;
+  private String name;
 
   /** Email address (or user@host style string anyway). */
-  protected String email;
+  private String email;
 
   /** Username of the user. */
-  protected String username;
+  private String username;
 
   /** Time (in UTC) when the identity was constructed. */
-  protected Timestamp when;
+  private Instant when;
 
   /** Offset from UTC */
-  protected int tz;
+  private int tz;
 
   /** If the user has a Gerrit account, their account identity. */
-  protected Account.Id accountId;
+  private Account.Id accountId;
 
   public String getName() {
     return name;
@@ -55,11 +55,11 @@
     return username;
   }
 
-  public Timestamp getDate() {
+  public Instant getDate() {
     return when;
   }
 
-  public void setDate(Timestamp d) {
+  public void setDate(Instant d) {
     when = d;
   }
 
diff --git a/java/com/google/gerrit/entities/converter/ChangeMessageProtoConverter.java b/java/com/google/gerrit/entities/converter/ChangeMessageProtoConverter.java
index eb2a381..edf921e 100644
--- a/java/com/google/gerrit/entities/converter/ChangeMessageProtoConverter.java
+++ b/java/com/google/gerrit/entities/converter/ChangeMessageProtoConverter.java
@@ -20,7 +20,7 @@
 import com.google.gerrit.entities.PatchSet;
 import com.google.gerrit.proto.Entities;
 import com.google.protobuf.Parser;
-import java.sql.Timestamp;
+import java.time.Instant;
 import java.util.Objects;
 
 @Immutable
@@ -44,9 +44,9 @@
     if (author != null) {
       builder.setAuthorId(accountIdConverter.toProto(author));
     }
-    Timestamp writtenOn = changeMessage.getWrittenOn();
+    Instant writtenOn = changeMessage.getWrittenOn();
     if (writtenOn != null) {
-      builder.setWrittenOn(writtenOn.getTime());
+      builder.setWrittenOn(writtenOn.toEpochMilli());
     }
     // Build proto with template representation of the message. Templates are parsed when message is
     // extracted from cache.
@@ -78,7 +78,7 @@
         proto.hasKey() ? changeMessageKeyConverter.fromProto(proto.getKey()) : null;
     Account.Id author =
         proto.hasAuthorId() ? accountIdConverter.fromProto(proto.getAuthorId()) : null;
-    Timestamp writtenOn = proto.hasWrittenOn() ? new Timestamp(proto.getWrittenOn()) : null;
+    Instant writtenOn = proto.hasWrittenOn() ? Instant.ofEpochMilli(proto.getWrittenOn()) : null;
     PatchSet.Id patchSetId =
         proto.hasPatchset() ? patchSetIdConverter.fromProto(proto.getPatchset()) : null;
     // Only template representation of the message is stored in entity. Templates should be replaced
diff --git a/java/com/google/gerrit/entities/converter/ChangeProtoConverter.java b/java/com/google/gerrit/entities/converter/ChangeProtoConverter.java
index 689b4aa..4903364 100644
--- a/java/com/google/gerrit/entities/converter/ChangeProtoConverter.java
+++ b/java/com/google/gerrit/entities/converter/ChangeProtoConverter.java
@@ -21,7 +21,7 @@
 import com.google.gerrit.entities.PatchSet;
 import com.google.gerrit.proto.Entities;
 import com.google.protobuf.Parser;
-import java.sql.Timestamp;
+import java.time.Instant;
 
 @Immutable
 public enum ChangeProtoConverter implements ProtoConverter<Entities.Change, Change> {
@@ -44,8 +44,8 @@
         Entities.Change.newBuilder()
             .setChangeId(changeIdConverter.toProto(change.getId()))
             .setChangeKey(changeKeyConverter.toProto(change.getKey()))
-            .setCreatedOn(change.getCreatedOn().getTime())
-            .setLastUpdatedOn(change.getLastUpdatedOn().getTime())
+            .setCreatedOn(change.getCreatedOn().toEpochMilli())
+            .setLastUpdatedOn(change.getLastUpdatedOn().toEpochMilli())
             .setOwnerAccountId(accountIdConverter.toProto(change.getOwner()))
             .setDest(branchNameConverter.toProto(change.getDest()))
             .setStatus(change.getStatus().getCode())
@@ -96,9 +96,9 @@
     BranchNameKey destination =
         proto.hasDest() ? branchNameConverter.fromProto(proto.getDest()) : null;
     Change change =
-        new Change(key, changeId, owner, destination, new Timestamp(proto.getCreatedOn()));
+        new Change(key, changeId, owner, destination, Instant.ofEpochMilli(proto.getCreatedOn()));
     if (proto.hasLastUpdatedOn()) {
-      change.setLastUpdatedOn(new Timestamp(proto.getLastUpdatedOn()));
+      change.setLastUpdatedOn(Instant.ofEpochMilli(proto.getLastUpdatedOn()));
     }
     Change.Status status = Change.Status.forCode((char) proto.getStatus());
     if (status != null) {
diff --git a/java/com/google/gerrit/entities/converter/PatchSetApprovalProtoConverter.java b/java/com/google/gerrit/entities/converter/PatchSetApprovalProtoConverter.java
index 9e77025..e8ef346 100644
--- a/java/com/google/gerrit/entities/converter/PatchSetApprovalProtoConverter.java
+++ b/java/com/google/gerrit/entities/converter/PatchSetApprovalProtoConverter.java
@@ -19,7 +19,7 @@
 import com.google.gerrit.entities.PatchSetApproval;
 import com.google.gerrit.proto.Entities;
 import com.google.protobuf.Parser;
-import java.sql.Timestamp;
+import java.time.Instant;
 import java.util.Objects;
 
 @Immutable
@@ -38,10 +38,11 @@
         Entities.PatchSetApproval.newBuilder()
             .setKey(patchSetApprovalKeyProtoConverter.toProto(patchSetApproval.key()))
             .setValue(patchSetApproval.value())
-            .setGranted(patchSetApproval.granted().getTime())
+            .setGranted(patchSetApproval.granted().toEpochMilli())
             .setPostSubmit(patchSetApproval.postSubmit())
             .setCopied(patchSetApproval.copied());
 
+    patchSetApproval.uuid().ifPresent(uuid -> builder.setUuid(uuid.get()));
     patchSetApproval.tag().ifPresent(builder::setTag);
     Account.Id realAccountId = patchSetApproval.realAccountId();
     // PatchSetApproval#getRealAccountId automatically delegates to PatchSetApproval#getAccountId if
@@ -61,9 +62,12 @@
         PatchSetApproval.builder()
             .key(patchSetApprovalKeyProtoConverter.fromProto(proto.getKey()))
             .value(proto.getValue())
-            .granted(new Timestamp(proto.getGranted()))
+            .granted(Instant.ofEpochMilli(proto.getGranted()))
             .postSubmit(proto.getPostSubmit())
             .copied(proto.getCopied());
+    if (proto.hasUuid()) {
+      builder.uuid(PatchSetApproval.uuid(proto.getUuid()));
+    }
     if (proto.hasTag()) {
       builder.tag(proto.getTag());
     }
diff --git a/java/com/google/gerrit/entities/converter/PatchSetProtoConverter.java b/java/com/google/gerrit/entities/converter/PatchSetProtoConverter.java
index 13a6e71..210972d 100644
--- a/java/com/google/gerrit/entities/converter/PatchSetProtoConverter.java
+++ b/java/com/google/gerrit/entities/converter/PatchSetProtoConverter.java
@@ -20,7 +20,7 @@
 import com.google.gerrit.entities.PatchSet;
 import com.google.gerrit.proto.Entities;
 import com.google.protobuf.Parser;
-import java.sql.Timestamp;
+import java.time.Instant;
 import java.util.List;
 import org.eclipse.jgit.lib.ObjectId;
 
@@ -42,7 +42,7 @@
             .setId(patchSetIdConverter.toProto(patchSet.id()))
             .setCommitId(objectIdConverter.toProto(patchSet.commitId()))
             .setUploaderAccountId(accountIdConverter.toProto(patchSet.uploader()))
-            .setCreatedOn(patchSet.createdOn().getTime());
+            .setCreatedOn(patchSet.createdOn().toEpochMilli());
     List<String> groups = patchSet.groups();
     if (!groups.isEmpty()) {
       builder.setGroups(PatchSet.joinGroups(groups));
@@ -84,7 +84,8 @@
             proto.hasUploaderAccountId()
                 ? accountIdConverter.fromProto(proto.getUploaderAccountId())
                 : Account.id(0))
-        .createdOn(proto.hasCreatedOn() ? new Timestamp(proto.getCreatedOn()) : new Timestamp(0));
+        .createdOn(
+            proto.hasCreatedOn() ? Instant.ofEpochMilli(proto.getCreatedOn()) : Instant.EPOCH);
 
     return builder.build();
   }
diff --git a/java/com/google/gerrit/exceptions/InternalServerWithUserMessageException.java b/java/com/google/gerrit/exceptions/MergeUpdateException.java
similarity index 64%
rename from java/com/google/gerrit/exceptions/InternalServerWithUserMessageException.java
rename to java/com/google/gerrit/exceptions/MergeUpdateException.java
index 452192c..b60ca57 100644
--- a/java/com/google/gerrit/exceptions/InternalServerWithUserMessageException.java
+++ b/java/com/google/gerrit/exceptions/MergeUpdateException.java
@@ -14,10 +14,15 @@
 
 package com.google.gerrit.exceptions;
 
-public class InternalServerWithUserMessageException extends RuntimeException {
+/**
+ * An exception used for changes that fail to merge. This exception has a user visible message
+ * unlike other {@link RuntimeException}s, because this is our way to improve the UX when
+ * submission/merges fail.
+ */
+public class MergeUpdateException extends RuntimeException {
   private static final long serialVersionUID = 1L;
 
-  public InternalServerWithUserMessageException(String msg, Throwable cause) {
-    super(msg, cause);
+  public MergeUpdateException(String userVisibleMessage, Throwable cause) {
+    super(userVisibleMessage, cause);
   }
 }
diff --git a/java/com/google/gerrit/extensions/api/changes/CherryPickInput.java b/java/com/google/gerrit/extensions/api/changes/CherryPickInput.java
index fb03bc5..232b2b5 100644
--- a/java/com/google/gerrit/extensions/api/changes/CherryPickInput.java
+++ b/java/com/google/gerrit/extensions/api/changes/CherryPickInput.java
@@ -31,4 +31,5 @@
   public boolean allowConflicts;
   public String topic;
   public boolean allowEmpty;
+  public Map<String, String> validationOptions;
 }
diff --git a/java/com/google/gerrit/extensions/api/changes/DeleteVoteInput.java b/java/com/google/gerrit/extensions/api/changes/DeleteVoteInput.java
index ee10a1d..8432c8f 100644
--- a/java/com/google/gerrit/extensions/api/changes/DeleteVoteInput.java
+++ b/java/com/google/gerrit/extensions/api/changes/DeleteVoteInput.java
@@ -25,4 +25,10 @@
   public NotifyHandling notify = NotifyHandling.ALL;
 
   public Map<RecipientType, NotifyInfo> notifyDetails;
+
+  /**
+   * Users in the attention set will not be added/removed from this endpoint call. Normally, users
+   * are added to the attention set upon deletion of their vote by other users.
+   */
+  public boolean ignoreAutomaticAttentionSetRules;
 }
diff --git a/java/com/google/gerrit/extensions/api/changes/RebaseInput.java b/java/com/google/gerrit/extensions/api/changes/RebaseInput.java
index 10559a3..e9b05cc 100644
--- a/java/com/google/gerrit/extensions/api/changes/RebaseInput.java
+++ b/java/com/google/gerrit/extensions/api/changes/RebaseInput.java
@@ -14,6 +14,8 @@
 
 package com.google.gerrit.extensions.api.changes;
 
+import java.util.Map;
+
 public class RebaseInput {
   public String base;
 
@@ -24,4 +26,6 @@
    * to indicate the conflicts.
    */
   public boolean allowConflicts;
+
+  public Map<String, String> validationOptions;
 }
diff --git a/java/com/google/gerrit/extensions/api/changes/RevisionApi.java b/java/com/google/gerrit/extensions/api/changes/RevisionApi.java
index 1307516..b659cca 100644
--- a/java/com/google/gerrit/extensions/api/changes/RevisionApi.java
+++ b/java/com/google/gerrit/extensions/api/changes/RevisionApi.java
@@ -51,12 +51,6 @@
 
   ChangeInfo submit(SubmitInput in) throws RestApiException;
 
-  default BinaryResult submitPreview() throws RestApiException {
-    return submitPreview("zip");
-  }
-
-  BinaryResult submitPreview(String format) throws RestApiException;
-
   ChangeApi cherryPick(CherryPickInput in) throws RestApiException;
 
   ChangeInfo cherryPickAsInfo(CherryPickInput in) throws RestApiException;
@@ -369,11 +363,6 @@
     }
 
     @Override
-    public BinaryResult submitPreview(String format) throws RestApiException {
-      throw new NotImplementedException();
-    }
-
-    @Override
     public SubmitType testSubmitType(TestSubmitRuleInput in) throws RestApiException {
       throw new NotImplementedException();
     }
diff --git a/java/com/google/gerrit/extensions/api/changes/SubmittedTogetherOption.java b/java/com/google/gerrit/extensions/api/changes/SubmittedTogetherOption.java
index e2cab4d..68a4e88 100644
--- a/java/com/google/gerrit/extensions/api/changes/SubmittedTogetherOption.java
+++ b/java/com/google/gerrit/extensions/api/changes/SubmittedTogetherOption.java
@@ -16,5 +16,6 @@
 
 /** Output options available for submitted_together requests. */
 public enum SubmittedTogetherOption {
-  NON_VISIBLE_CHANGES;
+  NON_VISIBLE_CHANGES,
+  TOPIC_CLOSURE;
 }
diff --git a/java/com/google/gerrit/extensions/api/projects/BranchInput.java b/java/com/google/gerrit/extensions/api/projects/BranchInput.java
index aaf69d9..aeefcd1 100644
--- a/java/com/google/gerrit/extensions/api/projects/BranchInput.java
+++ b/java/com/google/gerrit/extensions/api/projects/BranchInput.java
@@ -15,8 +15,10 @@
 package com.google.gerrit.extensions.api.projects;
 
 import com.google.gerrit.extensions.restapi.DefaultInput;
+import java.util.Map;
 
 public class BranchInput {
   @DefaultInput public String revision;
   public String ref;
+  public Map<String, String> validationOptions;
 }
diff --git a/java/com/google/gerrit/extensions/api/projects/TagInfo.java b/java/com/google/gerrit/extensions/api/projects/TagInfo.java
index a6269fe..61ea518 100644
--- a/java/com/google/gerrit/extensions/api/projects/TagInfo.java
+++ b/java/com/google/gerrit/extensions/api/projects/TagInfo.java
@@ -14,16 +14,22 @@
 
 package com.google.gerrit.extensions.api.projects;
 
+import com.google.gerrit.common.Nullable;
 import com.google.gerrit.extensions.common.GitPerson;
 import com.google.gerrit.extensions.common.WebLinkInfo;
 import java.sql.Timestamp;
+import java.time.Instant;
 import java.util.List;
 
 public class TagInfo extends RefInfo {
   public String object;
   public String message;
   public GitPerson tagger;
+
+  // TODO(issue-15508): Migrate timestamp fields in *Info/*Input classes from type Timestamp to
+  // Instant
   public Timestamp created;
+
   public List<WebLinkInfo> webLinks;
 
   public TagInfo(
@@ -39,8 +45,22 @@
     this.created = created;
   }
 
+  @SuppressWarnings("JdkObsolete")
+  public TagInfo(
+      String ref,
+      String revision,
+      Boolean canDelete,
+      List<WebLinkInfo> webLinks,
+      @Nullable Instant created) {
+    this.ref = ref;
+    this.revision = revision;
+    this.canDelete = canDelete;
+    this.webLinks = webLinks;
+    this.created = created != null ? Timestamp.from(created) : null;
+  }
+
   public TagInfo(String ref, String revision, Boolean canDelete, List<WebLinkInfo> webLinks) {
-    this(ref, revision, canDelete, webLinks, null);
+    this(ref, revision, canDelete, webLinks, (Instant) null);
   }
 
   public TagInfo(
@@ -66,8 +86,24 @@
       String message,
       GitPerson tagger,
       Boolean canDelete,
+      List<WebLinkInfo> webLinks,
+      Instant created) {
+    this(ref, revision, canDelete, webLinks, created);
+    this.object = object;
+    this.message = message;
+    this.tagger = tagger;
+    this.webLinks = webLinks;
+  }
+
+  public TagInfo(
+      String ref,
+      String revision,
+      String object,
+      String message,
+      GitPerson tagger,
+      Boolean canDelete,
       List<WebLinkInfo> webLinks) {
-    this(ref, revision, object, message, tagger, canDelete, webLinks, null);
+    this(ref, revision, object, message, tagger, canDelete, webLinks, (Instant) null);
     this.object = object;
     this.message = message;
     this.tagger = tagger;
diff --git a/java/com/google/gerrit/extensions/client/Comment.java b/java/com/google/gerrit/extensions/client/Comment.java
index 634992e..b8843d3 100644
--- a/java/com/google/gerrit/extensions/client/Comment.java
+++ b/java/com/google/gerrit/extensions/client/Comment.java
@@ -15,6 +15,7 @@
 package com.google.gerrit.extensions.client;
 
 import java.sql.Timestamp;
+import java.time.Instant;
 import java.util.Comparator;
 import java.util.Objects;
 
@@ -35,7 +36,11 @@
 
   public Range range;
   public String inReplyTo;
+
+  // TODO(issue-15508): Migrate timestamp fields in *Info/*Input classes from type Timestamp to
+  // Instant
   public Timestamp updated;
+
   public String message;
 
   /**
@@ -44,6 +49,20 @@
    */
   public String commitId;
 
+  // TODO(issue-15508): Migrate timestamp fields in *Info/*Input classes from type Timestamp to
+  // Instant
+  @SuppressWarnings("JdkObsolete")
+  public Instant getUpdated() {
+    return updated.toInstant();
+  }
+
+  // TODO(issue-15508): Migrate timestamp fields in *Info/*Input classes from type Timestamp to
+  // Instant
+  @SuppressWarnings("JdkObsolete")
+  public void setUpdated(Instant when) {
+    updated = Timestamp.from(when);
+  }
+
   public static class Range implements Comparable<Range> {
     private static final Comparator<Range> RANGE_COMPARATOR =
         Comparator.<Range>comparingInt(range -> range.startLine)
@@ -70,10 +89,10 @@
     public boolean equals(Object o) {
       if (o instanceof Range) {
         Range r = (Range) o;
-        return Objects.equals(startLine, r.startLine)
-            && Objects.equals(startCharacter, r.startCharacter)
-            && Objects.equals(endLine, r.endLine)
-            && Objects.equals(endCharacter, r.endCharacter);
+        return startLine == r.startLine
+            && startCharacter == r.startCharacter
+            && endLine == r.endLine
+            && endCharacter == r.endCharacter;
       }
       return false;
     }
@@ -110,6 +129,11 @@
     return 1;
   }
 
+  // This is a value class that allows adding attributes by subclassing.
+  // Doing this is discouraged and using composition rather than inheritance to add fields to value
+  // types is preferred. However this class is part of the extension API, hence we cannot change it
+  // without breaking the API. Hence suppress the EqualsGetClass warning here.
+  @SuppressWarnings("EqualsGetClass")
   @Override
   public boolean equals(Object o) {
     if (this == o) {
diff --git a/java/com/google/gerrit/extensions/client/GeneralPreferencesInfo.java b/java/com/google/gerrit/extensions/client/GeneralPreferencesInfo.java
index b26f435..6acf3f4 100644
--- a/java/com/google/gerrit/extensions/client/GeneralPreferencesInfo.java
+++ b/java/com/google/gerrit/extensions/client/GeneralPreferencesInfo.java
@@ -22,9 +22,6 @@
   /** Default number of items to display per page. */
   public static final int DEFAULT_PAGESIZE = 25;
 
-  /** Valid choices for the page size. */
-  public static final int[] PAGESIZE_CHOICES = {10, 25, 50, 100};
-
   /** Preferred method to download a change. */
   public enum DownloadCommand {
     PULL,
diff --git a/java/com/google/gerrit/extensions/common/AccountDetailInfo.java b/java/com/google/gerrit/extensions/common/AccountDetailInfo.java
index a2aeab2..a76a7f9 100644
--- a/java/com/google/gerrit/extensions/common/AccountDetailInfo.java
+++ b/java/com/google/gerrit/extensions/common/AccountDetailInfo.java
@@ -15,6 +15,7 @@
 package com.google.gerrit.extensions.common;
 
 import java.sql.Timestamp;
+import java.time.Instant;
 
 /**
  * Representation of a (detailed) account in the REST API.
@@ -27,9 +28,18 @@
  */
 public class AccountDetailInfo extends AccountInfo {
   /** The timestamp of when the account was registered. */
+  // TODO(issue-15508): Migrate timestamp fields in *Info/*Input classes from type Timestamp to
+  // Instant
   public Timestamp registeredOn;
 
   public AccountDetailInfo(Integer id) {
     super(id);
   }
+
+  // TODO(issue-15508): Migrate timestamp fields in *Info/*Input classes from type Timestamp to
+  // Instant
+  @SuppressWarnings("JdkObsolete")
+  public void setRegisteredOn(Instant registeredOn) {
+    this.registeredOn = Timestamp.from(registeredOn);
+  }
 }
diff --git a/java/com/google/gerrit/extensions/common/AccountExternalIdInfo.java b/java/com/google/gerrit/extensions/common/AccountExternalIdInfo.java
index e3e0fc8..b51e195 100644
--- a/java/com/google/gerrit/extensions/common/AccountExternalIdInfo.java
+++ b/java/com/google/gerrit/extensions/common/AccountExternalIdInfo.java
@@ -57,10 +57,10 @@
   public boolean equals(Object o) {
     if (o instanceof AccountExternalIdInfo) {
       AccountExternalIdInfo a = (AccountExternalIdInfo) o;
-      return (Objects.equals(a.identity, identity))
-          && (Objects.equals(a.emailAddress, emailAddress))
-          && (Objects.equals(a.trusted, trusted))
-          && (Objects.equals(a.canDelete, canDelete));
+      return Objects.equals(a.identity, identity)
+          && Objects.equals(a.emailAddress, emailAddress)
+          && Objects.equals(a.trusted, trusted)
+          && Objects.equals(a.canDelete, canDelete);
     }
     return false;
   }
diff --git a/java/com/google/gerrit/extensions/common/ApprovalInfo.java b/java/com/google/gerrit/extensions/common/ApprovalInfo.java
index bf72e83..4519add 100644
--- a/java/com/google/gerrit/extensions/common/ApprovalInfo.java
+++ b/java/com/google/gerrit/extensions/common/ApprovalInfo.java
@@ -16,6 +16,7 @@
 
 import com.google.gerrit.common.Nullable;
 import java.sql.Timestamp;
+import java.time.Instant;
 import java.util.Objects;
 
 /**
@@ -43,6 +44,8 @@
   public Integer value;
 
   /** The time and date describing when the approval was made. */
+  // TODO(issue-15508): Migrate timestamp fields in *Info/*Input classes from type Timestamp to
+  // Instant
   public Timestamp date;
 
   /** Whether this vote was made after the change was submitted. */
@@ -62,10 +65,10 @@
 
   public ApprovalInfo(
       Integer id,
-      Integer value,
+      @Nullable Integer value,
       @Nullable VotingRangeInfo permittedVotingRange,
       @Nullable String tag,
-      Timestamp date) {
+      @Nullable Timestamp date) {
     super(id);
     this.value = value;
     this.permittedVotingRange = permittedVotingRange;
@@ -73,6 +76,28 @@
     this.tag = tag;
   }
 
+  public ApprovalInfo(
+      Integer id,
+      @Nullable Integer value,
+      @Nullable VotingRangeInfo permittedVotingRange,
+      @Nullable String tag,
+      @Nullable Instant date) {
+    super(id);
+    this.value = value;
+    this.permittedVotingRange = permittedVotingRange;
+    this.tag = tag;
+    if (date != null) {
+      setDate(date);
+    }
+  }
+
+  // TODO(issue-15508): Migrate timestamp fields in *Info/*Input classes from type Timestamp to
+  // Instant
+  @SuppressWarnings("JdkObsolete")
+  public void setDate(Instant date) {
+    this.date = Timestamp.from(date);
+  }
+
   @Override
   public boolean equals(Object o) {
     if (o instanceof ApprovalInfo) {
@@ -88,6 +113,11 @@
   }
 
   @Override
+  public String toString() {
+    return super.toString() + ", value=" + this.value;
+  }
+
+  @Override
   public int hashCode() {
     return Objects.hash(super.hashCode(), tag, value, date, postSubmit, permittedVotingRange);
   }
diff --git a/java/com/google/gerrit/extensions/common/AttentionSetInfo.java b/java/com/google/gerrit/extensions/common/AttentionSetInfo.java
index d34ba6d..81dbc88 100644
--- a/java/com/google/gerrit/extensions/common/AttentionSetInfo.java
+++ b/java/com/google/gerrit/extensions/common/AttentionSetInfo.java
@@ -16,6 +16,7 @@
 
 import com.google.gerrit.common.Nullable;
 import java.sql.Timestamp;
+import java.time.Instant;
 import java.util.Objects;
 
 /**
@@ -28,8 +29,12 @@
 public class AttentionSetInfo {
   /** The user included in the attention set. */
   public AccountInfo account;
+
   /** The timestamp of the last update. */
+  // TODO(issue-15508): Migrate timestamp fields in *Info/*Input classes from type Timestamp to
+  // Instant
   public Timestamp lastUpdate;
+
   /** The human readable reason why the user was added. */
   public String reason;
 
@@ -51,6 +56,17 @@
     this.reasonAccount = reasonAccount;
   }
 
+  // TODO(issue-15508): Migrate timestamp fields in *Info/*Input classes from type Timestamp to
+  // Instant
+  @SuppressWarnings("JdkObsolete")
+  public AttentionSetInfo(
+      AccountInfo account, Instant lastUpdate, String reason, @Nullable AccountInfo reasonAccount) {
+    this.account = account;
+    this.lastUpdate = Timestamp.from(lastUpdate);
+    this.reason = reason;
+    this.reasonAccount = reasonAccount;
+  }
+
   protected AttentionSetInfo() {}
 
   @Override
diff --git a/java/com/google/gerrit/extensions/common/BlameInfo.java b/java/com/google/gerrit/extensions/common/BlameInfo.java
index df3f373..6ee677e 100644
--- a/java/com/google/gerrit/extensions/common/BlameInfo.java
+++ b/java/com/google/gerrit/extensions/common/BlameInfo.java
@@ -28,7 +28,7 @@
     if (this == o) {
       return true;
     }
-    if (o == null || getClass() != o.getClass()) {
+    if (o == null || !(o instanceof BlameInfo)) {
       return false;
     }
     BlameInfo blameInfo = (BlameInfo) o;
diff --git a/java/com/google/gerrit/extensions/common/ChangeInfo.java b/java/com/google/gerrit/extensions/common/ChangeInfo.java
index 2bb3dd7..40ae2ec 100644
--- a/java/com/google/gerrit/extensions/common/ChangeInfo.java
+++ b/java/com/google/gerrit/extensions/common/ChangeInfo.java
@@ -20,6 +20,7 @@
 import com.google.gerrit.extensions.client.ReviewerState;
 import com.google.gerrit.extensions.client.SubmitType;
 import java.sql.Timestamp;
+import java.time.Instant;
 import java.util.Collection;
 import java.util.List;
 import java.util.Map;
@@ -46,14 +47,20 @@
    */
   public Map<Integer, AttentionSetInfo> attentionSet;
 
+  public Map<Integer, AttentionSetInfo> removedFromAttentionSet;
+
   public AccountInfo assignee;
   public Collection<String> hashtags;
   public String changeId;
   public String subject;
   public ChangeStatus status;
+
+  // TODO(issue-15508): Migrate timestamp fields in *Info/*Input classes from type Timestamp to
+  // Instant
   public Timestamp created;
   public Timestamp updated;
   public Timestamp submitted;
+
   public AccountInfo submitter;
   public Boolean starred;
   public Collection<String> stars;
@@ -124,4 +131,47 @@
   public ChangeInfo(Map<String, RevisionInfo> revisions) {
     this.revisions = ImmutableMap.copyOf(revisions);
   }
+
+  // TODO(issue-15508): Migrate timestamp fields in *Info/*Input classes from type Timestamp to
+  // Instant
+  @SuppressWarnings("JdkObsolete")
+  public Instant getCreated() {
+    return created.toInstant();
+  }
+
+  // TODO(issue-15508): Migrate timestamp fields in *Info/*Input classes from type Timestamp to
+  // Instant
+  @SuppressWarnings("JdkObsolete")
+  public void setCreated(Instant when) {
+    created = Timestamp.from(when);
+  }
+
+  // TODO(issue-15508): Migrate timestamp fields in *Info/*Input classes from type Timestamp to
+  // Instant
+  @SuppressWarnings("JdkObsolete")
+  public Instant getUpdated() {
+    return updated.toInstant();
+  }
+
+  // TODO(issue-15508): Migrate timestamp fields in *Info/*Input classes from type Timestamp to
+  // Instant
+  @SuppressWarnings("JdkObsolete")
+  public void setUpdated(Instant when) {
+    updated = Timestamp.from(when);
+  }
+
+  // TODO(issue-15508): Migrate timestamp fields in *Info/*Input classes from type Timestamp to
+  // Instant
+  @SuppressWarnings("JdkObsolete")
+  public Instant getSubmitted() {
+    return submitted.toInstant();
+  }
+
+  // TODO(issue-15508): Migrate timestamp fields in *Info/*Input classes from type Timestamp to
+  // Instant
+  @SuppressWarnings("JdkObsolete")
+  public void setSubmitted(Instant when, AccountInfo who) {
+    submitted = Timestamp.from(when);
+    submitter = who;
+  }
 }
diff --git a/java/com/google/gerrit/extensions/common/ChangeMessageInfo.java b/java/com/google/gerrit/extensions/common/ChangeMessageInfo.java
index c1cb1627..51fe57c 100644
--- a/java/com/google/gerrit/extensions/common/ChangeMessageInfo.java
+++ b/java/com/google/gerrit/extensions/common/ChangeMessageInfo.java
@@ -14,7 +14,9 @@
 
 package com.google.gerrit.extensions.common;
 
+import com.google.common.collect.Iterables;
 import java.sql.Timestamp;
+import java.time.Instant;
 import java.util.Collection;
 import java.util.Objects;
 
@@ -24,7 +26,11 @@
   public String tag;
   public AccountInfo author;
   public AccountInfo realAuthor;
+
+  // TODO(issue-15508): Migrate timestamp fields in *Info/*Input classes from type Timestamp to
+  // Instant
   public Timestamp date;
+
   public String message;
   public Collection<AccountInfo> accountsInMessage;
   public Integer _revisionNumber;
@@ -35,6 +41,13 @@
     this.message = message;
   }
 
+  // TODO(issue-15508): Migrate timestamp fields in *Info/*Input classes from type Timestamp to
+  // Instant
+  @SuppressWarnings("JdkObsolete")
+  public void setDate(Instant when) {
+    date = Timestamp.from(when);
+  }
+
   @Override
   public boolean equals(Object o) {
     if (o instanceof ChangeMessageInfo) {
@@ -45,7 +58,10 @@
           && Objects.equals(realAuthor, cmi.realAuthor)
           && Objects.equals(date, cmi.date)
           && Objects.equals(message, cmi.message)
-          && Objects.equals(accountsInMessage, cmi.accountsInMessage)
+          && ((accountsInMessage == null && cmi.accountsInMessage == null)
+              || (accountsInMessage != null
+                  && cmi.accountsInMessage != null
+                  && Iterables.elementsEqual(accountsInMessage, cmi.accountsInMessage)))
           && Objects.equals(_revisionNumber, cmi._revisionNumber);
     }
     return false;
diff --git a/java/com/google/gerrit/extensions/common/GitPerson.java b/java/com/google/gerrit/extensions/common/GitPerson.java
index 8ed919e..df3e488 100644
--- a/java/com/google/gerrit/extensions/common/GitPerson.java
+++ b/java/com/google/gerrit/extensions/common/GitPerson.java
@@ -15,14 +15,26 @@
 package com.google.gerrit.extensions.common;
 
 import java.sql.Timestamp;
+import java.time.Instant;
 import java.util.Objects;
 
 public class GitPerson {
   public String name;
   public String email;
+
+  // TODO(issue-15508): Migrate timestamp fields in *Info/*Input classes from type Timestamp to
+  // Instant
   public Timestamp date;
+
   public int tz;
 
+  // TODO(issue-15508): Migrate timestamp fields in *Info/*Input classes from type Timestamp to
+  // Instant
+  @SuppressWarnings("JdkObsolete")
+  public void setDate(Instant when) {
+    date = Timestamp.from(when);
+  }
+
   @Override
   public boolean equals(Object o) {
     if (!(o instanceof GitPerson)) {
diff --git a/java/com/google/gerrit/extensions/common/GroupAuditEventInfo.java b/java/com/google/gerrit/extensions/common/GroupAuditEventInfo.java
index 711337a..9a13713 100644
--- a/java/com/google/gerrit/extensions/common/GroupAuditEventInfo.java
+++ b/java/com/google/gerrit/extensions/common/GroupAuditEventInfo.java
@@ -14,7 +14,9 @@
 
 package com.google.gerrit.extensions.common;
 
+import com.google.gerrit.common.Nullable;
 import java.sql.Timestamp;
+import java.time.Instant;
 import java.util.Optional;
 
 public abstract class GroupAuditEventInfo {
@@ -27,25 +29,62 @@
 
   public Type type;
   public AccountInfo user;
+
+  // TODO(issue-15508): Migrate timestamp fields in *Info/*Input classes from type Timestamp to
+  // Instant
   public Timestamp date;
 
+  // TODO(issue-15508): Migrate timestamp fields in *Info/*Input classes from type Timestamp to
+  // Instant
+  @SuppressWarnings("JdkObsolete")
   public static UserMemberAuditEventInfo createAddUserEvent(
       AccountInfo user, Timestamp date, AccountInfo member) {
-    return new UserMemberAuditEventInfo(Type.ADD_USER, user, Optional.of(date), member);
+    return new UserMemberAuditEventInfo(Type.ADD_USER, user, date.toInstant(), member);
+  }
+
+  public static UserMemberAuditEventInfo createAddUserEvent(
+      AccountInfo user, Instant date, AccountInfo member) {
+    return new UserMemberAuditEventInfo(Type.ADD_USER, user, date, member);
+  }
+
+  // TODO(issue-15508): Migrate timestamp fields in *Info/*Input classes from type Timestamp to
+  // Instant
+  @SuppressWarnings("JdkObsolete")
+  public static UserMemberAuditEventInfo createRemoveUserEvent(
+      AccountInfo user, Optional<Timestamp> date, AccountInfo member) {
+    return new UserMemberAuditEventInfo(
+        Type.REMOVE_USER, user, date.map(Timestamp::toInstant).orElse(null), member);
   }
 
   public static UserMemberAuditEventInfo createRemoveUserEvent(
-      AccountInfo user, Optional<Timestamp> date, AccountInfo member) {
+      AccountInfo user, @Nullable Instant date, AccountInfo member) {
     return new UserMemberAuditEventInfo(Type.REMOVE_USER, user, date, member);
   }
 
+  // TODO(issue-15508): Migrate timestamp fields in *Info/*Input classes from type Timestamp to
+  // Instant
+  @SuppressWarnings("JdkObsolete")
   public static GroupMemberAuditEventInfo createAddGroupEvent(
       AccountInfo user, Timestamp date, GroupInfo member) {
-    return new GroupMemberAuditEventInfo(Type.ADD_GROUP, user, Optional.of(date), member);
+    return new GroupMemberAuditEventInfo(Type.ADD_GROUP, user, date.toInstant(), member);
+  }
+
+  public static GroupMemberAuditEventInfo createAddGroupEvent(
+      AccountInfo user, Instant date, GroupInfo member) {
+    return new GroupMemberAuditEventInfo(Type.ADD_GROUP, user, date, member);
+  }
+
+  // TODO(issue-15508): Migrate timestamp fields in *Info/*Input classes from type Timestamp to
+  // Instant
+  @SuppressWarnings("JdkObsolete")
+  public static GroupMemberAuditEventInfo createRemoveGroupEvent(
+      AccountInfo user, Optional<Timestamp> date, GroupInfo member) {
+    return new GroupMemberAuditEventInfo(
+        Type.REMOVE_GROUP, user, date.map(Timestamp::toInstant).orElse(null), member);
   }
 
   public static GroupMemberAuditEventInfo createRemoveGroupEvent(
-      AccountInfo user, Optional<Timestamp> date, GroupInfo member) {
+      AccountInfo user, @Nullable Instant date, GroupInfo member) {
     return new GroupMemberAuditEventInfo(Type.REMOVE_GROUP, user, date, member);
   }
 
@@ -55,11 +94,20 @@
     this.date = date.orElse(null);
   }
 
+  // TODO(issue-15508): Migrate timestamp fields in *Info/*Input classes from type Timestamp to
+  // Instant
+  @SuppressWarnings("JdkObsolete")
+  protected GroupAuditEventInfo(Type type, AccountInfo user, @Nullable Instant date) {
+    this.type = type;
+    this.user = user;
+    this.date = date != null ? Timestamp.from(date) : null;
+  }
+
   public static class UserMemberAuditEventInfo extends GroupAuditEventInfo {
     public AccountInfo member;
 
     private UserMemberAuditEventInfo(
-        Type type, AccountInfo user, Optional<Timestamp> date, AccountInfo member) {
+        Type type, AccountInfo user, @Nullable Instant date, AccountInfo member) {
       super(type, user, date);
       this.member = member;
     }
@@ -69,7 +117,7 @@
     public GroupInfo member;
 
     private GroupMemberAuditEventInfo(
-        Type type, AccountInfo user, Optional<Timestamp> date, GroupInfo member) {
+        Type type, AccountInfo user, @Nullable Instant date, GroupInfo member) {
       super(type, user, date);
       this.member = member;
     }
diff --git a/java/com/google/gerrit/extensions/common/GroupInfo.java b/java/com/google/gerrit/extensions/common/GroupInfo.java
index b21475c..edbaa01 100644
--- a/java/com/google/gerrit/extensions/common/GroupInfo.java
+++ b/java/com/google/gerrit/extensions/common/GroupInfo.java
@@ -15,6 +15,7 @@
 package com.google.gerrit.extensions.common;
 
 import java.sql.Timestamp;
+import java.time.Instant;
 import java.util.List;
 
 public class GroupInfo extends GroupBaseInfo {
@@ -26,10 +27,28 @@
   public Integer groupId;
   public String owner;
   public String ownerId;
+
+  // TODO(issue-15508): Migrate timestamp fields in *Info/*Input classes from type Timestamp to
+  // Instant
   public Timestamp createdOn;
+
   public Boolean _moreGroups;
 
   // These fields are only supplied for internal groups, and only if requested.
   public List<AccountInfo> members;
   public List<GroupInfo> includes;
+
+  // TODO(issue-15508): Migrate timestamp fields in *Info/*Input classes from type Timestamp to
+  // Instant
+  @SuppressWarnings("JdkObsolete")
+  public Instant getCreatedOn() {
+    return createdOn.toInstant();
+  }
+
+  // TODO(issue-15508): Migrate timestamp fields in *Info/*Input classes from type Timestamp to
+  // Instant
+  @SuppressWarnings("JdkObsolete")
+  public void setCreatedOn(Instant when) {
+    createdOn = Timestamp.from(when);
+  }
 }
diff --git a/java/com/google/gerrit/extensions/common/LabelDefinitionInfo.java b/java/com/google/gerrit/extensions/common/LabelDefinitionInfo.java
index 6f733d6..d3baecd 100644
--- a/java/com/google/gerrit/extensions/common/LabelDefinitionInfo.java
+++ b/java/com/google/gerrit/extensions/common/LabelDefinitionInfo.java
@@ -19,6 +19,7 @@
 
 public class LabelDefinitionInfo {
   public String name;
+  public String description;
   public String projectName;
   public String function;
   public Map<String, String> values;
diff --git a/java/com/google/gerrit/extensions/common/LabelDefinitionInput.java b/java/com/google/gerrit/extensions/common/LabelDefinitionInput.java
index 38b76c1..1d580bb 100644
--- a/java/com/google/gerrit/extensions/common/LabelDefinitionInput.java
+++ b/java/com/google/gerrit/extensions/common/LabelDefinitionInput.java
@@ -19,6 +19,7 @@
 
 public class LabelDefinitionInput extends InputWithCommitMessage {
   public String name;
+  public String description;
   public String function;
   public Map<String, String> values;
   public Short defaultValue;
diff --git a/java/com/google/gerrit/extensions/common/LabelInfo.java b/java/com/google/gerrit/extensions/common/LabelInfo.java
index 44bcdaf..cdd3b18 100644
--- a/java/com/google/gerrit/extensions/common/LabelInfo.java
+++ b/java/com/google/gerrit/extensions/common/LabelInfo.java
@@ -27,6 +27,7 @@
 
   public Map<String, String> values;
 
+  public String description;
   public Short value;
   public Short defaultValue;
   public Boolean optional;
diff --git a/java/com/google/gerrit/extensions/common/ReviewerUpdateInfo.java b/java/com/google/gerrit/extensions/common/ReviewerUpdateInfo.java
index 37e1ceb..36682f6 100644
--- a/java/com/google/gerrit/extensions/common/ReviewerUpdateInfo.java
+++ b/java/com/google/gerrit/extensions/common/ReviewerUpdateInfo.java
@@ -16,14 +16,31 @@
 
 import com.google.gerrit.extensions.client.ReviewerState;
 import java.sql.Timestamp;
+import java.time.Instant;
 import java.util.Objects;
 
 public class ReviewerUpdateInfo {
+  // TODO(issue-15508): Migrate timestamp fields in *Info/*Input classes from type Timestamp to
+  // Instant
   public Timestamp updated;
+
   public AccountInfo updatedBy;
   public AccountInfo reviewer;
   public ReviewerState state;
 
+  public ReviewerUpdateInfo() {}
+
+  // TODO(issue-15508): Migrate timestamp fields in *Info/*Input classes from type Timestamp to
+  // Instant
+  @SuppressWarnings("JdkObsolete")
+  public ReviewerUpdateInfo(
+      Instant updated, AccountInfo updatedBy, AccountInfo reviewer, ReviewerState state) {
+    this.updated = Timestamp.from(updated);
+    this.updatedBy = updatedBy;
+    this.reviewer = reviewer;
+    this.state = state;
+  }
+
   @Override
   public boolean equals(Object o) {
     if (o instanceof ReviewerUpdateInfo) {
diff --git a/java/com/google/gerrit/extensions/common/RevisionInfo.java b/java/com/google/gerrit/extensions/common/RevisionInfo.java
index f710ab7..7c52c8c 100644
--- a/java/com/google/gerrit/extensions/common/RevisionInfo.java
+++ b/java/com/google/gerrit/extensions/common/RevisionInfo.java
@@ -16,6 +16,7 @@
 
 import com.google.gerrit.extensions.client.ChangeKind;
 import java.sql.Timestamp;
+import java.time.Instant;
 import java.util.Map;
 import java.util.Objects;
 
@@ -25,7 +26,11 @@
   public transient boolean isCurrent;
   public ChangeKind kind;
   public int _number;
+
+  // TODO(issue-15508): Migrate timestamp fields in *Info/*Input classes from type Timestamp to
+  // Instant
   public Timestamp created;
+
   public AccountInfo uploader;
   public String ref;
   public Map<String, FetchInfo> fetch;
@@ -51,6 +56,13 @@
     this.uploader = uploader;
   }
 
+  // TODO(issue-15508): Migrate timestamp fields in *Info/*Input classes from type Timestamp to
+  // Instant
+  @SuppressWarnings("JdkObsolete")
+  public void setCreated(Instant date) {
+    this.created = Timestamp.from(date);
+  }
+
   @Override
   public boolean equals(Object o) {
     if (o instanceof RevisionInfo) {
diff --git a/java/com/google/gerrit/extensions/common/ServerInfo.java b/java/com/google/gerrit/extensions/common/ServerInfo.java
index bc7fcfd..ce65240 100644
--- a/java/com/google/gerrit/extensions/common/ServerInfo.java
+++ b/java/com/google/gerrit/extensions/common/ServerInfo.java
@@ -14,6 +14,8 @@
 
 package com.google.gerrit.extensions.common;
 
+import java.util.List;
+
 /** API response containing values from {@code gerrit.config} as nested objects. */
 public class ServerInfo {
   public AccountsInfo accounts;
@@ -28,4 +30,5 @@
   public UserConfigInfo user;
   public ReceiveInfo receive;
   public String defaultTheme;
+  public List<String> submitRequirementDashboardColumns;
 }
diff --git a/java/com/google/gerrit/extensions/common/SubmitRecordInfo.java b/java/com/google/gerrit/extensions/common/SubmitRecordInfo.java
index 09c9841..d957733 100644
--- a/java/com/google/gerrit/extensions/common/SubmitRecordInfo.java
+++ b/java/com/google/gerrit/extensions/common/SubmitRecordInfo.java
@@ -15,6 +15,7 @@
 package com.google.gerrit.extensions.common;
 
 import java.util.List;
+import java.util.Objects;
 
 /** API response containing a {@link com.google.gerrit.entities.SubmitRecord} entity. */
 public class SubmitRecordInfo {
@@ -36,8 +37,27 @@
     }
 
     public String label;
-    public Status status;
+    public Label.Status status;
     public AccountInfo appliedBy;
+
+    @Override
+    public boolean equals(Object o) {
+      if (this == o) {
+        return true;
+      }
+      if (!(o instanceof Label)) {
+        return false;
+      }
+      Label that = (Label) o;
+      return Objects.equals(label, that.label)
+          && status == that.status
+          && Objects.equals(appliedBy, that.appliedBy);
+    }
+
+    @Override
+    public int hashCode() {
+      return Objects.hash(label, status, appliedBy);
+    }
   }
 
   public String ruleName;
@@ -45,4 +65,25 @@
   public List<Label> labels;
   public List<LegacySubmitRequirementInfo> requirements;
   public String errorMessage;
+
+  @Override
+  public boolean equals(Object o) {
+    if (this == o) {
+      return true;
+    }
+    if (!(o instanceof SubmitRecordInfo)) {
+      return false;
+    }
+    SubmitRecordInfo that = (SubmitRecordInfo) o;
+    return Objects.equals(ruleName, that.ruleName)
+        && status == that.status
+        && Objects.equals(labels, that.labels)
+        && Objects.equals(requirements, that.requirements)
+        && Objects.equals(errorMessage, that.errorMessage);
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(ruleName, status, labels, requirements, errorMessage);
+  }
 }
diff --git a/java/com/google/gerrit/extensions/common/SubmitRequirementExpressionInfo.java b/java/com/google/gerrit/extensions/common/SubmitRequirementExpressionInfo.java
index 4d1fce2..b4731f2 100644
--- a/java/com/google/gerrit/extensions/common/SubmitRequirementExpressionInfo.java
+++ b/java/com/google/gerrit/extensions/common/SubmitRequirementExpressionInfo.java
@@ -15,6 +15,7 @@
 package com.google.gerrit.extensions.common;
 
 import java.util.List;
+import java.util.Objects;
 
 /** Result of evaluating a single submit requirement expression. */
 public class SubmitRequirementExpressionInfo {
@@ -36,4 +37,31 @@
    * has two atoms: ["branch:refs/heads/foo", "project:bar"].
    */
   public List<String> failingAtoms;
+
+  /**
+   * Optional error message. Contains an explanation of why the submit requirement expression failed
+   * during its evaluation.
+   */
+  public String errorMessage;
+
+  @Override
+  public boolean equals(Object o) {
+    if (this == o) {
+      return true;
+    }
+    if (!(o instanceof SubmitRequirementExpressionInfo)) {
+      return false;
+    }
+    SubmitRequirementExpressionInfo that = (SubmitRequirementExpressionInfo) o;
+    return fulfilled == that.fulfilled
+        && Objects.equals(expression, that.expression)
+        && Objects.equals(passingAtoms, that.passingAtoms)
+        && Objects.equals(failingAtoms, that.failingAtoms)
+        && Objects.equals(errorMessage, that.errorMessage);
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(expression, fulfilled, passingAtoms, failingAtoms, errorMessage);
+  }
 }
diff --git a/java/com/google/gerrit/extensions/common/SubmitRequirementResultInfo.java b/java/com/google/gerrit/extensions/common/SubmitRequirementResultInfo.java
index 3d50f13..cf0d53c 100644
--- a/java/com/google/gerrit/extensions/common/SubmitRequirementResultInfo.java
+++ b/java/com/google/gerrit/extensions/common/SubmitRequirementResultInfo.java
@@ -14,6 +14,9 @@
 
 package com.google.gerrit.extensions.common;
 
+import com.google.gerrit.common.Nullable;
+import java.util.Objects;
+
 /** Result of evaluating a submit requirement on a change. */
 public class SubmitRequirementResultInfo {
   public enum Status {
@@ -41,7 +44,13 @@
      * Any of the applicability, submittability or override expressions contain invalid syntax and
      * are not parsable.
      */
-    ERROR
+    ERROR,
+
+    /**
+     * The "submit requirement" was bypassed during submission, e.g. by pushing for review with the
+     * %submit option.
+     */
+    FORCED
   }
 
   /** Submit requirement name. */
@@ -57,11 +66,41 @@
   public boolean isLegacy;
 
   /** Result of evaluating the applicability expression. */
-  public SubmitRequirementExpressionInfo applicabilityExpressionResult;
+  @Nullable public SubmitRequirementExpressionInfo applicabilityExpressionResult;
 
   /** Result of evaluating the submittability expression. */
-  public SubmitRequirementExpressionInfo submittabilityExpressionResult;
+  @Nullable public SubmitRequirementExpressionInfo submittabilityExpressionResult;
 
   /** Result of evaluating the override expression. */
-  public SubmitRequirementExpressionInfo overrideExpressionResult;
+  @Nullable public SubmitRequirementExpressionInfo overrideExpressionResult;
+
+  @Override
+  public boolean equals(Object o) {
+    if (this == o) {
+      return true;
+    }
+    if (!(o instanceof SubmitRequirementResultInfo)) {
+      return false;
+    }
+    SubmitRequirementResultInfo that = (SubmitRequirementResultInfo) o;
+    return isLegacy == that.isLegacy
+        && Objects.equals(name, that.name)
+        && Objects.equals(description, that.description)
+        && status == that.status
+        && Objects.equals(applicabilityExpressionResult, that.applicabilityExpressionResult)
+        && Objects.equals(submittabilityExpressionResult, that.submittabilityExpressionResult)
+        && Objects.equals(overrideExpressionResult, that.overrideExpressionResult);
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(
+        name,
+        description,
+        status,
+        isLegacy,
+        applicabilityExpressionResult,
+        submittabilityExpressionResult,
+        overrideExpressionResult);
+  }
 }
diff --git a/java/com/google/gerrit/extensions/common/testing/GitPersonSubject.java b/java/com/google/gerrit/extensions/common/testing/GitPersonSubject.java
index d827d5d..cb9d855 100644
--- a/java/com/google/gerrit/extensions/common/testing/GitPersonSubject.java
+++ b/java/com/google/gerrit/extensions/common/testing/GitPersonSubject.java
@@ -24,7 +24,6 @@
 import com.google.common.truth.Subject;
 import com.google.gerrit.extensions.common.GitPerson;
 import java.sql.Timestamp;
-import java.util.Date;
 import org.eclipse.jgit.lib.PersonIdent;
 
 public class GitPersonSubject extends Subject {
@@ -71,11 +70,16 @@
     tz().isEqualTo(other.tz);
   }
 
+  // TODO(issue-15508): Migrate timestamp fields in *Info/*Input classes from type Timestamp to
+  // Instant
+  // TODO(issue-15517): Fix the JdkObsolete issue with Date once JGit's PersonIdent class supports
+  // Instants
+  @SuppressWarnings("JdkObsolete")
   public void matches(PersonIdent ident) {
     isNotNull();
     name().isEqualTo(ident.getName());
     email().isEqualTo(ident.getEmailAddress());
-    check("roundedDate()").that(new Date(gitPerson.date.getTime())).isEqualTo(ident.getWhen());
+    check("roundedDate()").that(gitPerson.date.getTime()).isEqualTo(ident.getWhen().getTime());
     tz().isEqualTo(ident.getTimeZoneOffset());
   }
 }
diff --git a/java/com/google/gerrit/extensions/events/ChangeEvent.java b/java/com/google/gerrit/extensions/events/ChangeEvent.java
index def75b7..6542d8e 100644
--- a/java/com/google/gerrit/extensions/events/ChangeEvent.java
+++ b/java/com/google/gerrit/extensions/events/ChangeEvent.java
@@ -16,7 +16,7 @@
 
 import com.google.gerrit.extensions.common.AccountInfo;
 import com.google.gerrit.extensions.common.ChangeInfo;
-import java.sql.Timestamp;
+import java.time.Instant;
 
 /** Interface to be extended by Events with a Change. */
 public interface ChangeEvent extends GerritEvent {
@@ -29,5 +29,5 @@
 
   AccountInfo getWho();
 
-  Timestamp getWhen();
+  Instant getWhen();
 }
diff --git a/java/com/google/gerrit/extensions/events/GitBatchRefUpdateListener.java b/java/com/google/gerrit/extensions/events/GitBatchRefUpdateListener.java
new file mode 100644
index 0000000..3d638c8
--- /dev/null
+++ b/java/com/google/gerrit/extensions/events/GitBatchRefUpdateListener.java
@@ -0,0 +1,50 @@
+// Copyright (C) 2022 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.extensions.events;
+
+import com.google.gerrit.common.Nullable;
+import com.google.gerrit.extensions.annotations.ExtensionPoint;
+import com.google.gerrit.extensions.common.AccountInfo;
+import java.util.Set;
+
+/** Notified when one or more references are modified. */
+@ExtensionPoint
+public interface GitBatchRefUpdateListener {
+  interface Event extends ProjectEvent {
+    Set<UpdatedRef> getUpdatedRefs();
+
+    Set<String> getRefNames();
+
+    /** The updater, could be null if it's the server. */
+    @Nullable
+    AccountInfo getUpdater();
+  }
+
+  interface UpdatedRef {
+    public String getRefName();
+
+    public String getOldObjectId();
+
+    public String getNewObjectId();
+
+    public boolean isCreate();
+
+    public boolean isDelete();
+
+    public boolean isNonFastForward();
+  }
+
+  void onGitBatchRefUpdate(Event event);
+}
diff --git a/java/com/google/gerrit/extensions/events/GitReferenceUpdatedListener.java b/java/com/google/gerrit/extensions/events/GitReferenceUpdatedListener.java
index bf922f8..0fec0f0 100644
--- a/java/com/google/gerrit/extensions/events/GitReferenceUpdatedListener.java
+++ b/java/com/google/gerrit/extensions/events/GitReferenceUpdatedListener.java
@@ -21,18 +21,7 @@
 /** Notified when one or more references are modified. */
 @ExtensionPoint
 public interface GitReferenceUpdatedListener {
-  interface Event extends ProjectEvent {
-    String getRefName();
-
-    String getOldObjectId();
-
-    String getNewObjectId();
-
-    boolean isCreate();
-
-    boolean isDelete();
-
-    boolean isNonFastForward();
+  interface Event extends ProjectEvent, GitBatchRefUpdateListener.UpdatedRef {
     /** The updater, could be null if it's the server. */
     @Nullable
     AccountInfo getUpdater();
diff --git a/java/com/google/gerrit/extensions/registration/DynamicMap.java b/java/com/google/gerrit/extensions/registration/DynamicMap.java
index 48b1279..6fd2c03 100644
--- a/java/com/google/gerrit/extensions/registration/DynamicMap.java
+++ b/java/com/google/gerrit/extensions/registration/DynamicMap.java
@@ -24,8 +24,8 @@
 import java.util.Collections;
 import java.util.Iterator;
 import java.util.Map;
-import java.util.SortedMap;
-import java.util.SortedSet;
+import java.util.NavigableMap;
+import java.util.NavigableSet;
 import java.util.TreeMap;
 import java.util.TreeSet;
 import java.util.concurrent.ConcurrentHashMap;
@@ -116,14 +116,14 @@
   /**
    * Get the names of all running plugins supplying this type.
    *
-   * @return sorted set of active plugins that supply at least one item.
+   * @return navigatable set of active plugins that supply at least one item.
    */
-  public SortedSet<String> plugins() {
-    SortedSet<String> r = new TreeSet<>();
+  public NavigableSet<String> plugins() {
+    NavigableSet<String> r = new TreeSet<>();
     for (NamePair p : items.keySet()) {
       r.add(p.pluginName);
     }
-    return Collections.unmodifiableSortedSet(r);
+    return Collections.unmodifiableNavigableSet(r);
   }
 
   /**
@@ -132,21 +132,21 @@
    * @param pluginName name of the plugin.
    * @return items exported by a plugin, keyed by the export name.
    */
-  public SortedMap<String, Provider<T>> byPlugin(String pluginName) {
-    SortedMap<String, Provider<T>> r = new TreeMap<>();
+  public NavigableMap<String, Provider<T>> byPlugin(String pluginName) {
+    NavigableMap<String, Provider<T>> r = new TreeMap<>();
     for (Map.Entry<NamePair, Provider<T>> e : items.entrySet()) {
       if (e.getKey().pluginName.equals(pluginName)) {
         r.put(e.getKey().exportName, e.getValue());
       }
     }
-    return Collections.unmodifiableSortedMap(r);
+    return Collections.unmodifiableNavigableMap(r);
   }
 
   /** Iterate through all entries in an undefined order. */
   @Override
   public Iterator<Extension<T>> iterator() {
     final Iterator<Map.Entry<NamePair, Provider<T>>> i = items.entrySet().iterator();
-    return new Iterator<Extension<T>>() {
+    return new Iterator<>() {
       @Override
       public boolean hasNext() {
         return i.hasNext();
diff --git a/java/com/google/gerrit/extensions/registration/DynamicSet.java b/java/com/google/gerrit/extensions/registration/DynamicSet.java
index b2e871e..a0b2c6a 100644
--- a/java/com/google/gerrit/extensions/registration/DynamicSet.java
+++ b/java/com/google/gerrit/extensions/registration/DynamicSet.java
@@ -153,7 +153,7 @@
   @Override
   public Iterator<T> iterator() {
     Iterator<Extension<T>> entryIterator = entries().iterator();
-    return new Iterator<T>() {
+    return new Iterator<>() {
       @Override
       public boolean hasNext() {
         return entryIterator.hasNext();
@@ -170,7 +170,7 @@
   public Iterable<Extension<T>> entries() {
     final Iterator<AtomicReference<Extension<T>>> itr = items.iterator();
     return () ->
-        new Iterator<Extension<T>>() {
+        new Iterator<>() {
           private Extension<T> next;
 
           @Override
diff --git a/java/com/google/gerrit/extensions/registration/DynamicSetProvider.java b/java/com/google/gerrit/extensions/registration/DynamicSetProvider.java
index 832933b..d8999e3 100644
--- a/java/com/google/gerrit/extensions/registration/DynamicSetProvider.java
+++ b/java/com/google/gerrit/extensions/registration/DynamicSetProvider.java
@@ -14,13 +14,13 @@
 
 package com.google.gerrit.extensions.registration;
 
+import com.google.common.collect.ImmutableList;
 import com.google.inject.Binding;
 import com.google.inject.Inject;
 import com.google.inject.Injector;
 import com.google.inject.Provider;
 import com.google.inject.TypeLiteral;
 import java.util.ArrayList;
-import java.util.Collections;
 import java.util.List;
 import java.util.concurrent.atomic.AtomicReference;
 
@@ -38,11 +38,12 @@
     return new DynamicSet<>(find(injector, type));
   }
 
-  private static <T> List<AtomicReference<Extension<T>>> find(Injector src, TypeLiteral<T> type) {
+  private static <T> ImmutableList<AtomicReference<Extension<T>>> find(
+      Injector src, TypeLiteral<T> type) {
     List<Binding<T>> bindings = src.findBindingsByType(type);
     int cnt = bindings != null ? bindings.size() : 0;
     if (cnt == 0) {
-      return Collections.emptyList();
+      return ImmutableList.of();
     }
     List<AtomicReference<Extension<T>>> r = new ArrayList<>(cnt);
     for (Binding<T> b : bindings) {
@@ -50,6 +51,6 @@
         r.add(new AtomicReference<>(new Extension<>(PluginName.GERRIT, b.getProvider())));
       }
     }
-    return r;
+    return ImmutableList.copyOf(r);
   }
 }
diff --git a/java/com/google/gerrit/extensions/registration/PrivateInternals_DynamicTypes.java b/java/com/google/gerrit/extensions/registration/PrivateInternals_DynamicTypes.java
index fd31fcd..5b528cb 100644
--- a/java/com/google/gerrit/extensions/registration/PrivateInternals_DynamicTypes.java
+++ b/java/com/google/gerrit/extensions/registration/PrivateInternals_DynamicTypes.java
@@ -14,6 +14,7 @@
 
 package com.google.gerrit.extensions.registration;
 
+import com.google.common.collect.ImmutableList;
 import com.google.gerrit.extensions.events.LifecycleListener;
 import com.google.inject.Binding;
 import com.google.inject.Inject;
@@ -80,10 +81,10 @@
     return Collections.unmodifiableMap(m);
   }
 
-  public static List<RegistrationHandle> attachItems(
+  public static ImmutableList<RegistrationHandle> attachItems(
       Injector src, String pluginName, Map<TypeLiteral<?>, DynamicItem<?>> items) {
     if (src == null || items == null || items.isEmpty()) {
-      return Collections.emptyList();
+      return ImmutableList.of();
     }
 
     List<RegistrationHandle> handles = new ArrayList<>(4);
@@ -103,13 +104,13 @@
       remove(handles);
       throw e;
     }
-    return handles;
+    return ImmutableList.copyOf(handles);
   }
 
-  public static List<RegistrationHandle> attachSets(
+  public static ImmutableList<RegistrationHandle> attachSets(
       Injector src, String pluginName, Map<TypeLiteral<?>, DynamicSet<?>> sets) {
     if (src == null || sets == null || sets.isEmpty()) {
-      return Collections.emptyList();
+      return ImmutableList.of();
     }
 
     List<RegistrationHandle> handles = new ArrayList<>(4);
@@ -131,13 +132,13 @@
       remove(handles);
       throw e;
     }
-    return handles;
+    return ImmutableList.copyOf(handles);
   }
 
-  public static List<RegistrationHandle> attachMaps(
+  public static ImmutableList<RegistrationHandle> attachMaps(
       Injector src, String pluginName, Map<TypeLiteral<?>, DynamicMap<?>> maps) {
     if (src == null || maps == null || maps.isEmpty()) {
-      return Collections.emptyList();
+      return ImmutableList.of();
     }
 
     List<RegistrationHandle> handles = new ArrayList<>(4);
@@ -160,7 +161,7 @@
       remove(handles);
       throw e;
     }
-    return handles;
+    return ImmutableList.copyOf(handles);
   }
 
   public static LifecycleListener registerInParentInjectors() {
diff --git a/java/com/google/gerrit/extensions/validators/CommentValidationContext.java b/java/com/google/gerrit/extensions/validators/CommentValidationContext.java
index db08058..2c9d8f2 100644
--- a/java/com/google/gerrit/extensions/validators/CommentValidationContext.java
+++ b/java/com/google/gerrit/extensions/validators/CommentValidationContext.java
@@ -34,7 +34,10 @@
   /** Returns the project the comment is being added to. */
   public abstract String getProject();
 
-  public static CommentValidationContext create(int changeId, String project) {
-    return new AutoValue_CommentValidationContext(changeId, project);
+  /** Returns the ref name the comment is being added to. */
+  public abstract String getRefName();
+
+  public static CommentValidationContext create(int changeId, String project, String refName) {
+    return new AutoValue_CommentValidationContext(changeId, project, refName);
   }
 }
diff --git a/java/com/google/gerrit/extensions/webui/PatchSetWebLink.java b/java/com/google/gerrit/extensions/webui/PatchSetWebLink.java
index 0e8e28e..74bccbd 100644
--- a/java/com/google/gerrit/extensions/webui/PatchSetWebLink.java
+++ b/java/com/google/gerrit/extensions/webui/PatchSetWebLink.java
@@ -37,6 +37,34 @@
    * @return WebLinkInfo that links to patch set in external service, null if there should be no
    *     link.
    */
+  @Deprecated
   WebLinkInfo getPatchSetWebLink(
       String projectName, String commit, String commitMessage, String branchName);
+
+  /**
+   * {@link com.google.gerrit.extensions.common.WebLinkInfo} describing a link from a patch set to
+   * an external service.
+   *
+   * <p>In order for the web link to be visible {@link
+   * com.google.gerrit.extensions.common.WebLinkInfo#url} and {@link
+   * com.google.gerrit.extensions.common.WebLinkInfo#name} must be set.
+   *
+   * <p>
+   *
+   * @param projectName name of the project
+   * @param commit commit of the patch set
+   * @param commitMessage the commit message of the change
+   * @param branchName target branch of the change
+   * @param changeKey the changeID for this change
+   * @return WebLinkInfo that links to patch set in external service, null if there should be no
+   *     link.
+   */
+  default WebLinkInfo getPatchSetWebLink(
+      String projectName,
+      String commit,
+      String commitMessage,
+      String branchName,
+      String changeKey) {
+    return getPatchSetWebLink(projectName, commit, commitMessage, branchName);
+  }
 }
diff --git a/java/com/google/gerrit/gpg/PublicKeyChecker.java b/java/com/google/gerrit/gpg/PublicKeyChecker.java
index 27530e7..0a96212 100644
--- a/java/com/google/gerrit/gpg/PublicKeyChecker.java
+++ b/java/com/google/gerrit/gpg/PublicKeyChecker.java
@@ -32,9 +32,9 @@
 import com.google.common.flogger.FluentLogger;
 import com.google.gerrit.extensions.common.GpgKeyInfo.Status;
 import java.io.IOException;
+import java.time.Instant;
 import java.util.ArrayList;
 import java.util.Arrays;
-import java.util.Date;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.Iterator;
@@ -62,7 +62,7 @@
   private PublicKeyStore store;
   private Map<Long, Fingerprint> trusted;
   private int maxTrustDepth;
-  private Date effectiveTime = new Date();
+  private Instant effectiveTime = Instant.now();
 
   /**
    * Enable web-of-trust checks.
@@ -111,12 +111,12 @@
    * @param effectiveTime effective time.
    * @return a reference to this object.
    */
-  public PublicKeyChecker setEffectiveTime(Date effectiveTime) {
+  public PublicKeyChecker setEffectiveTime(Instant effectiveTime) {
     this.effectiveTime = effectiveTime;
     return this;
   }
 
-  protected Date getEffectiveTime() {
+  protected Instant getEffectiveTime() {
     return effectiveTime;
   }
 
@@ -183,13 +183,13 @@
     return CheckResult.create(status, problems);
   }
 
-  private CheckResult checkBasic(PGPPublicKey key, Date now) {
+  private CheckResult checkBasic(PGPPublicKey key, Instant now) {
     List<String> problems = new ArrayList<>(2);
     gatherRevocationProblems(key, now, problems);
 
     long validMs = key.getValidSeconds() * 1000;
     if (validMs != 0) {
-      long msSinceCreation = now.getTime() - key.getCreationTime().getTime();
+      long msSinceCreation = now.toEpochMilli() - getCreationTime(key).toEpochMilli();
       if (msSinceCreation > validMs) {
         problems.add("Key is expired");
       }
@@ -197,7 +197,7 @@
     return CheckResult.create(problems);
   }
 
-  private void gatherRevocationProblems(PGPPublicKey key, Date now, List<String> problems) {
+  private void gatherRevocationProblems(PGPPublicKey key, Instant now, List<String> problems) {
     try {
       List<PGPSignature> revocations = new ArrayList<>();
       Map<Long, RevocationKey> revokers = new HashMap<>();
@@ -216,7 +216,7 @@
   }
 
   private static boolean isRevocationValid(
-      PGPSignature revocation, RevocationReason reason, Date now) {
+      PGPSignature revocation, RevocationReason reason, Instant now) {
     // RFC4880 states:
     // "If a key has been revoked because of a compromise, all signatures
     // created by that key are suspect. However, if it was merely superseded or
@@ -226,11 +226,14 @@
     // consider the revocation reason and timestamp when checking whether a
     // signature (data or certification) is valid.
     return reason.getRevocationReason() == KEY_COMPROMISED
-        || revocation.getCreationTime().before(now);
+        || PushCertificateChecker.getCreationTime(revocation).isBefore(now);
   }
 
   private PGPSignature scanRevocations(
-      PGPPublicKey key, Date now, List<PGPSignature> revocations, Map<Long, RevocationKey> revokers)
+      PGPPublicKey key,
+      Instant now,
+      List<PGPSignature> revocations,
+      Map<Long, RevocationKey> revokers)
       throws PGPException {
     @SuppressWarnings("unchecked")
     Iterator<PGPSignature> allSigs = key.getSignatures();
@@ -305,7 +308,7 @@
       if (rk.getAlgorithm() != revoker.getAlgorithm()) {
         continue;
       }
-      if (!checkBasic(rk, revocation.getCreationTime()).isOk()) {
+      if (!checkBasic(rk, PushCertificateChecker.getCreationTime(revocation)).isOk()) {
         // Revoker's key was expired or revoked at time of revocation, so the
         // revocation is invalid.
         continue;
@@ -469,4 +472,9 @@
     }
     return null;
   }
+
+  @SuppressWarnings("JdkObsolete")
+  private static Instant getCreationTime(PGPPublicKey key) {
+    return key.getCreationTime().toInstant();
+  }
 }
diff --git a/java/com/google/gerrit/gpg/PushCertificateChecker.java b/java/com/google/gerrit/gpg/PushCertificateChecker.java
index 36a4af7..17ca5a4 100644
--- a/java/com/google/gerrit/gpg/PushCertificateChecker.java
+++ b/java/com/google/gerrit/gpg/PushCertificateChecker.java
@@ -25,6 +25,7 @@
 import com.google.gerrit.extensions.common.GpgKeyInfo.Status;
 import java.io.ByteArrayInputStream;
 import java.io.IOException;
+import java.time.Instant;
 import java.util.ArrayList;
 import java.util.List;
 import org.bouncycastle.bcpg.ArmoredInputStream;
@@ -106,7 +107,7 @@
       }
     } catch (PGPException | IOException e) {
       String msg = "Internal error checking push certificate";
-      logger.atSevere().withCause(e).log(msg);
+      logger.atSevere().withCause(e).log("%s", msg);
       results.add(CheckResult.bad(msg));
     }
 
@@ -205,7 +206,7 @@
           null, CheckResult.bad("Signature by " + keyIdToString(sig.getKeyID()) + " is not valid"));
     }
     CheckResult result =
-        publicKeyChecker.setStore(store).setEffectiveTime(sig.getCreationTime()).check(signer);
+        publicKeyChecker.setStore(store).setEffectiveTime(getCreationTime(sig)).check(signer);
     if (!result.getProblems().isEmpty()) {
       StringBuilder err =
           new StringBuilder("Invalid public key ")
@@ -216,4 +217,9 @@
     }
     return new Result(signer, result);
   }
+
+  @SuppressWarnings("JdkObsolete")
+  public static Instant getCreationTime(PGPSignature signature) {
+    return signature.getCreationTime().toInstant();
+  }
 }
diff --git a/java/com/google/gerrit/gpg/server/DeleteGpgKey.java b/java/com/google/gerrit/gpg/server/DeleteGpgKey.java
index e0c921d..bcc8631 100644
--- a/java/com/google/gerrit/gpg/server/DeleteGpgKey.java
+++ b/java/com/google/gerrit/gpg/server/DeleteGpgKey.java
@@ -95,7 +95,7 @@
 
       CommitBuilder cb = new CommitBuilder();
       PersonIdent committer = serverIdent.get();
-      cb.setAuthor(rsrc.getUser().newCommitterIdent(committer.getWhen(), committer.getTimeZone()));
+      cb.setAuthor(rsrc.getUser().newCommitterIdent(committer));
       cb.setCommitter(committer);
       cb.setMessage("Delete public key " + keyIdToString(key.getKeyID()));
 
diff --git a/java/com/google/gerrit/gpg/server/GpgKey.java b/java/com/google/gerrit/gpg/server/GpgKey.java
index aa6b6f4..fbe97ad 100644
--- a/java/com/google/gerrit/gpg/server/GpgKey.java
+++ b/java/com/google/gerrit/gpg/server/GpgKey.java
@@ -21,8 +21,7 @@
 import org.bouncycastle.openpgp.PGPPublicKeyRing;
 
 public class GpgKey extends AccountResource {
-  public static final TypeLiteral<RestView<GpgKey>> GPG_KEY_KIND =
-      new TypeLiteral<RestView<GpgKey>>() {};
+  public static final TypeLiteral<RestView<GpgKey>> GPG_KEY_KIND = new TypeLiteral<>() {};
 
   private final PGPPublicKeyRing keyRing;
 
diff --git a/java/com/google/gerrit/gpg/server/PostGpgKeys.java b/java/com/google/gerrit/gpg/server/PostGpgKeys.java
index d46b344..3341806 100644
--- a/java/com/google/gerrit/gpg/server/PostGpgKeys.java
+++ b/java/com/google/gerrit/gpg/server/PostGpgKeys.java
@@ -164,7 +164,7 @@
     }
   }
 
-  private Map<ExternalId, Fingerprint> readKeysToRemove(
+  private ImmutableMap<ExternalId, Fingerprint> readKeysToRemove(
       GpgKeysInput input, Collection<ExternalId> existingExtIds) {
     if (input.delete == null || input.delete.isEmpty()) {
       return ImmutableMap.of();
@@ -179,10 +179,11 @@
         // Skip removal.
       }
     }
-    return fingerprints;
+    return ImmutableMap.copyOf(fingerprints);
   }
 
-  private List<PGPPublicKeyRing> readKeysToAdd(GpgKeysInput input, Collection<Fingerprint> toRemove)
+  private ImmutableList<PGPPublicKeyRing> readKeysToAdd(
+      GpgKeysInput input, Collection<Fingerprint> toRemove)
       throws BadRequestException, IOException {
     if (input.add == null || input.add.isEmpty()) {
       return ImmutableList.of();
@@ -206,7 +207,7 @@
         throw new BadRequestException("Failed to parse GPG keys", e);
       }
     }
-    return keyRings;
+    return ImmutableList.copyOf(keyRings);
   }
 
   private void storeKeys(
@@ -249,7 +250,7 @@
       }
       CommitBuilder cb = new CommitBuilder();
       PersonIdent committer = serverIdent.get();
-      cb.setAuthor(user.newCommitterIdent(committer.getWhen(), committer.getTimeZone()));
+      cb.setAuthor(user.newCommitterIdent(committer));
       cb.setCommitter(committer);
 
       RefUpdate.Result saveResult = store.save(cb);
diff --git a/java/com/google/gerrit/httpd/BUILD b/java/com/google/gerrit/httpd/BUILD
index ea7c609..1284829 100644
--- a/java/com/google/gerrit/httpd/BUILD
+++ b/java/com/google/gerrit/httpd/BUILD
@@ -37,7 +37,7 @@
         "//lib:soy",
         "//lib/auto:auto-value",
         "//lib/auto:auto-value-annotations",
-        "//lib/commons:lang",
+        "//lib/commons:lang3",
         "//lib/flogger:api",
         "//lib/guice",
         "//lib/guice:guice-assistedinject",
diff --git a/java/com/google/gerrit/httpd/CanonicalWebUrl.java b/java/com/google/gerrit/httpd/CanonicalWebUrl.java
index 437ddf3..3b04884 100644
--- a/java/com/google/gerrit/httpd/CanonicalWebUrl.java
+++ b/java/com/google/gerrit/httpd/CanonicalWebUrl.java
@@ -37,6 +37,7 @@
     return url != null ? url : computeFromRequest(req);
   }
 
+  @SuppressWarnings("JdkObsolete")
   static String computeFromRequest(HttpServletRequest req) {
     StringBuffer url = req.getRequestURL();
     try {
diff --git a/java/com/google/gerrit/httpd/CookieBase64.java b/java/com/google/gerrit/httpd/CookieBase64.java
index 52cfde7..376ae1d 100644
--- a/java/com/google/gerrit/httpd/CookieBase64.java
+++ b/java/com/google/gerrit/httpd/CookieBase64.java
@@ -75,7 +75,7 @@
         out.append(enc[(inBuff >>> 18)]);
         out.append(enc[(inBuff >>> 12) & 0x3f]);
         out.append(enc[(inBuff >>> 6) & 0x3f]);
-        out.append(enc[(inBuff) & 0x3f]);
+        out.append(enc[inBuff & 0x3f]);
         break;
 
       case 2:
diff --git a/java/com/google/gerrit/httpd/GitOverHttpServlet.java b/java/com/google/gerrit/httpd/GitOverHttpServlet.java
index 5ed0629..189d081 100644
--- a/java/com/google/gerrit/httpd/GitOverHttpServlet.java
+++ b/java/com/google/gerrit/httpd/GitOverHttpServlet.java
@@ -499,6 +499,7 @@
         }
       } catch (Throwable e) {
         logger.atSevere().withCause(e).log(
+            "%s",
             MessageFormat.format(
                 HttpServerText.get().internalErrorDuringUploadPack,
                 ServletUtils.getRepository(req)));
@@ -526,7 +527,7 @@
         throws ServiceNotAuthorizedException {
       final ProjectState state = (ProjectState) req.getAttribute(ATT_STATE);
 
-      if (!(userProvider.get().isIdentifiedUser())) {
+      if (!userProvider.get().isIdentifiedUser()) {
         // Anonymous users are not permitted to push.
         throw new ServiceNotAuthorizedException();
       }
@@ -633,7 +634,7 @@
         return;
       }
 
-      if (!(userProvider.get().isIdentifiedUser())) {
+      if (!userProvider.get().isIdentifiedUser()) {
         chain.doFilter(request, responseWrapper);
         return;
       }
diff --git a/java/com/google/gerrit/httpd/HttpdModule.java b/java/com/google/gerrit/httpd/HttpdModule.java
index 1f1ec2f..41cef7a 100644
--- a/java/com/google/gerrit/httpd/HttpdModule.java
+++ b/java/com/google/gerrit/httpd/HttpdModule.java
@@ -1,3 +1,17 @@
+// Copyright (C) 2021 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package com.google.gerrit.httpd;
 
 import com.google.gerrit.extensions.annotations.Exports;
diff --git a/java/com/google/gerrit/httpd/ProjectBasicAuthFilter.java b/java/com/google/gerrit/httpd/ProjectBasicAuthFilter.java
index a421139..b0c7615 100644
--- a/java/com/google/gerrit/httpd/ProjectBasicAuthFilter.java
+++ b/java/com/google/gerrit/httpd/ProjectBasicAuthFilter.java
@@ -186,7 +186,7 @@
       if (passwordVerifier.checkPassword(who.externalIds(), username, password)) {
         return succeedAuthentication(who, null);
       }
-      logger.atWarning().withCause(e).log(authenticationFailedMsg(username, req));
+      logger.atWarning().withCause(e).log("%s", authenticationFailedMsg(username, req));
       rsp.sendError(SC_UNAUTHORIZED);
       return false;
     } catch (AuthenticationFailedException e) {
@@ -200,7 +200,7 @@
       rsp.sendError(SC_SERVICE_UNAVAILABLE);
       return false;
     } catch (AccountException e) {
-      logger.atWarning().withCause(e).log(authenticationFailedMsg(username, req));
+      logger.atWarning().withCause(e).log("%s", authenticationFailedMsg(username, req));
       rsp.sendError(SC_UNAUTHORIZED);
       return false;
     }
@@ -214,8 +214,8 @@
   private boolean failAuthentication(Response rsp, String username, HttpServletRequest req)
       throws IOException {
     logger.atWarning().log(
-        authenticationFailedMsg(username, req)
-            + ": password does not match the one stored in Gerrit");
+        "%s: password does not match the one stored in Gerrit",
+        authenticationFailedMsg(username, req));
     rsp.sendError(SC_UNAUTHORIZED);
     return false;
   }
diff --git a/java/com/google/gerrit/httpd/ProjectOAuthFilter.java b/java/com/google/gerrit/httpd/ProjectOAuthFilter.java
index fa53053..de6ae50 100644
--- a/java/com/google/gerrit/httpd/ProjectOAuthFilter.java
+++ b/java/com/google/gerrit/httpd/ProjectOAuthFilter.java
@@ -158,8 +158,8 @@
         accountCache.getByUsername(authInfo.username).filter(a -> a.account().isActive());
     if (!who.isPresent()) {
       logger.atWarning().log(
-          authenticationFailedMsg(authInfo.username, req)
-              + ": account inactive or not provisioned in Gerrit");
+          "%s: account inactive or not provisioned in Gerrit",
+          authenticationFailedMsg(authInfo.username, req));
       rsp.sendError(SC_UNAUTHORIZED);
       return false;
     }
@@ -180,7 +180,7 @@
       ws.setAccessPathOk(AccessPath.REST_API, true);
       return true;
     } catch (AccountException e) {
-      logger.atWarning().withCause(e).log(authenticationFailedMsg(authInfo.username, req));
+      logger.atWarning().withCause(e).log("%s", authenticationFailedMsg(authInfo.username, req));
       rsp.sendError(SC_UNAUTHORIZED);
       return false;
     }
diff --git a/java/com/google/gerrit/httpd/RequireSslFilter.java b/java/com/google/gerrit/httpd/RequireSslFilter.java
index a4a87e2..ca3c3d8 100644
--- a/java/com/google/gerrit/httpd/RequireSslFilter.java
+++ b/java/com/google/gerrit/httpd/RequireSslFilter.java
@@ -78,10 +78,7 @@
       //
       final String url;
       if (isLocalHost(req)) {
-        final StringBuffer b = req.getRequestURL();
-        b.replace(0, b.indexOf(":"), "https");
-        url = b.toString();
-
+        url = getLocalHostUrl(req);
       } else {
         url = urlProvider.get() + req.getServletPath();
       }
@@ -90,6 +87,13 @@
     }
   }
 
+  @SuppressWarnings("JdkObsolete")
+  private static String getLocalHostUrl(HttpServletRequest req) {
+    StringBuffer b = req.getRequestURL();
+    b.replace(0, b.indexOf(":"), "https");
+    return b.toString();
+  }
+
   private static boolean isSecure(HttpServletRequest req) {
     return "https".equals(req.getScheme()) || req.isSecure();
   }
diff --git a/java/com/google/gerrit/httpd/auth/container/HttpsClientSslCertAuthFilter.java b/java/com/google/gerrit/httpd/auth/container/HttpsClientSslCertAuthFilter.java
index 820c7a2..59a7379 100644
--- a/java/com/google/gerrit/httpd/auth/container/HttpsClientSslCertAuthFilter.java
+++ b/java/com/google/gerrit/httpd/auth/container/HttpsClientSslCertAuthFilter.java
@@ -14,7 +14,6 @@
 
 package com.google.gerrit.httpd.auth.container;
 
-import com.google.common.flogger.FluentLogger;
 import com.google.gerrit.extensions.registration.DynamicItem;
 import com.google.gerrit.httpd.WebSession;
 import com.google.gerrit.server.account.AccountException;
@@ -36,8 +35,6 @@
 
 @Singleton
 class HttpsClientSslCertAuthFilter implements Filter {
-  private static final FluentLogger logger = FluentLogger.forEnclosingClass();
-
   private static final Pattern REGEX_USERID = Pattern.compile("CN=([^,]*)");
 
   private final DynamicItem<WebSession> webSession;
@@ -79,9 +76,7 @@
     try {
       arsp = accountManager.authenticate(areq);
     } catch (AccountException e) {
-      String err = "Unable to authenticate user \"" + userName + "\"";
-      logger.atSevere().withCause(e).log(err);
-      throw new ServletException(err, e);
+      throw new ServletException("Unable to authenticate user \"" + userName + "\"", e);
     }
     webSession.get().login(arsp, true);
     chain.doFilter(req, rsp);
diff --git a/java/com/google/gerrit/httpd/auth/oauth/OAuthSession.java b/java/com/google/gerrit/httpd/auth/oauth/OAuthSession.java
index a3f8fbda..297505a 100644
--- a/java/com/google/gerrit/httpd/auth/oauth/OAuthSession.java
+++ b/java/com/google/gerrit/httpd/auth/oauth/OAuthSession.java
@@ -190,7 +190,7 @@
     } else if (claimedId.isPresent() && !actualId.isPresent()) {
       // Claimed account already exists: link to it.
       //
-      logger.atInfo().log("OAuth2: linking claimed identity to %s", claimedId.get().toString());
+      logger.atInfo().log("OAuth2: linking claimed identity to %s", claimedId.get());
       try {
         accountManager.link(claimedId.get(), req);
       } catch (ConfigInvalidException e) {
diff --git a/java/com/google/gerrit/httpd/auth/oauth/OAuthWebFilter.java b/java/com/google/gerrit/httpd/auth/oauth/OAuthWebFilter.java
index 2642a543..935762f 100644
--- a/java/com/google/gerrit/httpd/auth/oauth/OAuthWebFilter.java
+++ b/java/com/google/gerrit/httpd/auth/oauth/OAuthWebFilter.java
@@ -31,9 +31,9 @@
 import com.google.inject.Singleton;
 import java.io.IOException;
 import java.util.Map;
+import java.util.NavigableMap;
+import java.util.NavigableSet;
 import java.util.Set;
-import java.util.SortedMap;
-import java.util.SortedSet;
 import javax.servlet.Filter;
 import javax.servlet.FilterChain;
 import javax.servlet.FilterConfig;
@@ -175,12 +175,12 @@
   }
 
   private void pickSSOServiceProvider() throws ServletException {
-    SortedSet<String> plugins = oauthServiceProviders.plugins();
+    NavigableSet<String> plugins = oauthServiceProviders.plugins();
     if (plugins.isEmpty()) {
       throw new ServletException("OAuth service provider wasn't installed");
     }
     if (plugins.size() == 1) {
-      SortedMap<String, Provider<OAuthServiceProvider>> services =
+      NavigableMap<String, Provider<OAuthServiceProvider>> services =
           oauthServiceProviders.byPlugin(Iterables.getOnlyElement(plugins));
       if (services.size() == 1) {
         ssoProvider = Iterables.getOnlyElement(services.values()).get();
diff --git a/java/com/google/gerrit/httpd/auth/openid/OAuthWebFilterOverOpenID.java b/java/com/google/gerrit/httpd/auth/openid/OAuthWebFilterOverOpenID.java
index 2e8585d..3d9c819 100644
--- a/java/com/google/gerrit/httpd/auth/openid/OAuthWebFilterOverOpenID.java
+++ b/java/com/google/gerrit/httpd/auth/openid/OAuthWebFilterOverOpenID.java
@@ -21,8 +21,8 @@
 import com.google.inject.Provider;
 import com.google.inject.Singleton;
 import java.io.IOException;
-import java.util.SortedMap;
-import java.util.SortedSet;
+import java.util.NavigableMap;
+import java.util.NavigableSet;
 import javax.servlet.Filter;
 import javax.servlet.FilterChain;
 import javax.servlet.FilterConfig;
@@ -79,9 +79,9 @@
   }
 
   private void pickSSOServiceProvider() {
-    SortedSet<String> plugins = oauthServiceProviders.plugins();
+    NavigableSet<String> plugins = oauthServiceProviders.plugins();
     if (plugins.size() == 1) {
-      SortedMap<String, Provider<OAuthServiceProvider>> services =
+      NavigableMap<String, Provider<OAuthServiceProvider>> services =
           oauthServiceProviders.byPlugin(Iterables.getOnlyElement(plugins));
       if (services.size() == 1) {
         ssoProvider = Iterables.getOnlyElement(services.values()).get();
diff --git a/java/com/google/gerrit/httpd/gitweb/GitwebServlet.java b/java/com/google/gerrit/httpd/gitweb/GitwebServlet.java
index 4c18afd..4c31253 100644
--- a/java/com/google/gerrit/httpd/gitweb/GitwebServlet.java
+++ b/java/com/google/gerrit/httpd/gitweb/GitwebServlet.java
@@ -75,7 +75,7 @@
 import java.net.URISyntaxException;
 import java.nio.file.Files;
 import java.nio.file.Path;
-import java.util.Enumeration;
+import java.util.Collections;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.List;
@@ -137,7 +137,7 @@
     getProjectRoot(allProjects);
 
     final String url = gitwebConfig.getUrl();
-    if ((url != null) && (!url.equals("gitweb"))) {
+    if (url != null && !url.equals("gitweb")) {
       URI uri = null;
       try {
         uri = new URI(url);
@@ -573,9 +573,7 @@
     env.set("SERVER_PROTOCOL", req.getProtocol());
     env.set("SERVER_SOFTWARE", getServletContext().getServerInfo());
 
-    final Enumeration<String> hdrs = enumerateHeaderNames(req);
-    while (hdrs.hasMoreElements()) {
-      final String name = hdrs.nextElement();
+    for (String name : getHeaderNames(req)) {
       final String value = req.getHeader(name);
       env.set("HTTP_" + name.toUpperCase().replace('-', '_'), value);
     }
@@ -720,7 +718,7 @@
                         .collect(Collectors.joining("\n"))
                         .trim();
                 if (!err.isEmpty()) {
-                  logger.atSevere().log(err);
+                  logger.atSevere().log("%s", err);
                 }
               } catch (IOException e) {
                 logger.atSevere().withCause(e).log("Unexpected error copying stderr from CGI");
@@ -730,10 +728,6 @@
         .start();
   }
 
-  private static Enumeration<String> enumerateHeaderNames(HttpServletRequest req) {
-    return req.getHeaderNames();
-  }
-
   private void readCgiHeaders(HttpServletResponse res, InputStream in) throws IOException {
     String line;
     while (!(line = readLine(in)).isEmpty()) {
@@ -774,6 +768,11 @@
     return buf.toString().trim();
   }
 
+  @SuppressWarnings("JdkObsolete")
+  private static Iterable<String> getHeaderNames(HttpServletRequest req) {
+    return Collections.list(req.getHeaderNames());
+  }
+
   /** private utility class that manages the Environment passed to exec. */
   private static class EnvList {
     private Map<String, String> envMap;
diff --git a/java/com/google/gerrit/httpd/init/WebAppInitializer.java b/java/com/google/gerrit/httpd/init/WebAppInitializer.java
index 68cf1b2..0073ec2 100644
--- a/java/com/google/gerrit/httpd/init/WebAppInitializer.java
+++ b/java/com/google/gerrit/httpd/init/WebAppInitializer.java
@@ -210,7 +210,7 @@
           buf.append("\nResolve above errors before continuing.");
           buf.append("\nComplete stack trace follows:");
         }
-        logger.atSevere().withCause(first.getCause()).log(buf.toString());
+        logger.atSevere().withCause(first.getCause()).log("%s", buf);
         throw new CreationException(Collections.singleton(first));
       }
 
@@ -345,7 +345,7 @@
         });
     modules.add(new DefaultUrlFormatterModule());
 
-    SshSessionFactoryInitializer.init(config);
+    SshSessionFactoryInitializer.init();
     modules.add(SshKeyCacheImpl.module());
     modules.add(
         new AbstractModule() {
diff --git a/java/com/google/gerrit/httpd/plugins/HttpPluginServlet.java b/java/com/google/gerrit/httpd/plugins/HttpPluginServlet.java
index 97752a0..a03aa36 100644
--- a/java/com/google/gerrit/httpd/plugins/HttpPluginServlet.java
+++ b/java/com/google/gerrit/httpd/plugins/HttpPluginServlet.java
@@ -68,7 +68,6 @@
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.util.ArrayList;
-import java.util.Collections;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Locale;
@@ -86,7 +85,7 @@
 import javax.servlet.http.HttpServlet;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
-import org.apache.commons.lang.StringUtils;
+import org.apache.commons.lang3.StringUtils;
 import org.eclipse.jgit.lib.Config;
 import org.eclipse.jgit.util.IO;
 import org.eclipse.jgit.util.RawParseUtils;
@@ -447,8 +446,7 @@
           return false;
         };
 
-    List<PluginEntry> entries =
-        Collections.list(scanner.entries()).stream().filter(filter).collect(toList());
+    List<PluginEntry> entries = scanner.entries().filter(filter).collect(toList());
     for (PluginEntry entry : entries) {
       String name = entry.getName().substring(prefix.length());
       if (name.startsWith("cmd-")) {
@@ -520,7 +518,7 @@
     macros.put("URL", url);
 
     Matcher m = Pattern.compile("(\\\\)?@([A-Z_]+)@").matcher(md);
-    StringBuffer sb = new StringBuffer();
+    StringBuilder sb = new StringBuilder();
     while (m.find()) {
       String key = m.group(2);
       String val = macros.get(key);
diff --git a/java/com/google/gerrit/httpd/plugins/PluginServletContext.java b/java/com/google/gerrit/httpd/plugins/PluginServletContext.java
index 5a8fa31..5e875d7 100644
--- a/java/com/google/gerrit/httpd/plugins/PluginServletContext.java
+++ b/java/com/google/gerrit/httpd/plugins/PluginServletContext.java
@@ -61,11 +61,11 @@
       try {
         handler = API.class.getDeclaredMethod(method.getName(), method.getParameterTypes());
       } catch (NoSuchMethodException e) {
-        String msg =
-            String.format(
-                "%s does not implement %s", PluginServletContext.class, method.toGenericString());
-        logger.atSevere().withCause(e).log(msg);
-        throw new NoSuchMethodError(msg);
+        throw new NoSuchMethodError(
+                String.format(
+                    "%s does not implement %s",
+                    PluginServletContext.class, method.toGenericString()))
+            .initCause(e);
       }
       return handler.invoke(this, args);
     }
diff --git a/java/com/google/gerrit/httpd/raw/IndexHtmlUtil.java b/java/com/google/gerrit/httpd/raw/IndexHtmlUtil.java
index 445a73a..ce22ae8 100644
--- a/java/com/google/gerrit/httpd/raw/IndexHtmlUtil.java
+++ b/java/com/google/gerrit/httpd/raw/IndexHtmlUtil.java
@@ -97,7 +97,8 @@
             IndexPreloadingUtil.computeChangeRequestsPath(requestedPath, page).get());
         break;
       case DIFF:
-        data.put("defaultDiffDetailHex", ListOption.toHex(IndexPreloadingUtil.DIFF_OPTIONS));
+        data.put(
+            "defaultChangeDetailHex", ListOption.toHex(IndexPreloadingUtil.CHANGE_DETAIL_OPTIONS));
         data.put(
             "changeRequestsPath",
             IndexPreloadingUtil.computeChangeRequestsPath(requestedPath, page).get());
diff --git a/java/com/google/gerrit/httpd/raw/IndexPreloadingUtil.java b/java/com/google/gerrit/httpd/raw/IndexPreloadingUtil.java
index 3bdcb1a..fa9a820 100644
--- a/java/com/google/gerrit/httpd/raw/IndexPreloadingUtil.java
+++ b/java/com/google/gerrit/httpd/raw/IndexPreloadingUtil.java
@@ -89,7 +89,10 @@
           .map(query -> query.replaceAll("\\$\\{user}", "self"))
           .collect(toImmutableList());
   public static final ImmutableSet<ListChangesOption> DASHBOARD_OPTIONS =
-      ImmutableSet.of(ListChangesOption.LABELS, ListChangesOption.DETAILED_ACCOUNTS);
+      ImmutableSet.of(
+          ListChangesOption.LABELS,
+          ListChangesOption.DETAILED_ACCOUNTS,
+          ListChangesOption.SUBMIT_REQUIREMENTS);
 
   public static final ImmutableSet<ListChangesOption> CHANGE_DETAIL_OPTIONS =
       ImmutableSet.of(
@@ -101,13 +104,8 @@
           ListChangesOption.MESSAGES,
           ListChangesOption.SUBMITTABLE,
           ListChangesOption.WEB_LINKS,
-          ListChangesOption.SKIP_DIFFSTAT);
-
-  public static final ImmutableSet<ListChangesOption> DIFF_OPTIONS =
-      ImmutableSet.of(
-          ListChangesOption.ALL_COMMITS,
-          ListChangesOption.ALL_REVISIONS,
-          ListChangesOption.SKIP_DIFFSTAT);
+          ListChangesOption.SKIP_DIFFSTAT,
+          ListChangesOption.SUBMIT_REQUIREMENTS);
 
   public static String getPath(@Nullable String requestedURL) throws URISyntaxException {
     if (requestedURL == null) {
diff --git a/java/com/google/gerrit/httpd/raw/IndexServlet.java b/java/com/google/gerrit/httpd/raw/IndexServlet.java
index 3f2c202..fcb821e 100644
--- a/java/com/google/gerrit/httpd/raw/IndexServlet.java
+++ b/java/com/google/gerrit/httpd/raw/IndexServlet.java
@@ -38,6 +38,8 @@
 
 public class IndexServlet extends HttpServlet {
   private static final long serialVersionUID = 1L;
+  private static final String POLY_GERRIT_INDEX_HTML_SOY =
+      "com/google/gerrit/httpd/raw/PolyGerritIndexHtml.soy";
 
   @Nullable private final String canonicalUrl;
   @Nullable private final String cdnPath;
@@ -60,7 +62,7 @@
     this.experimentFeatures = experimentFeatures;
     this.soySauce =
         SoyFileSet.builder()
-            .add(Resources.getResource("com/google/gerrit/httpd/raw/PolyGerritIndexHtml.soy"))
+            .add(Resources.getResource(POLY_GERRIT_INDEX_HTML_SOY), POLY_GERRIT_INDEX_HTML_SOY)
             .build()
             .compileTemplates();
     this.urlOrdainer =
@@ -74,7 +76,6 @@
     SoySauce.Renderer renderer;
     try {
       Map<String, String[]> parameterMap = req.getParameterMap();
-      String requestUrl = req.getRequestURL() == null ? null : req.getRequestURL().toString();
       // TODO(hiesel): Remove URL ordainer as parameter once Soy is consistent
       ImmutableMap<String, Object> templateData =
           IndexHtmlUtil.templateData(
@@ -85,7 +86,7 @@
               faviconPath,
               parameterMap,
               urlOrdainer,
-              requestUrl);
+              getRequestUrl(req));
       renderer = soySauce.renderTemplate("com.google.gerrit.httpd.raw.Index").setData(templateData);
     } catch (URISyntaxException | RestApiException e) {
       throw new IOException(e);
@@ -98,4 +99,13 @@
       w.write(renderer.renderHtml().get().toString().getBytes(UTF_8));
     }
   }
+
+  @SuppressWarnings("JdkObsolete")
+  @Nullable
+  private static String getRequestUrl(HttpServletRequest req) {
+    if (req.getRequestURL() == null) {
+      return null;
+    }
+    return req.getRequestURL().toString();
+  }
 }
diff --git a/java/com/google/gerrit/httpd/raw/StaticModule.java b/java/com/google/gerrit/httpd/raw/StaticModule.java
index aa32169..8e8a9d2 100644
--- a/java/com/google/gerrit/httpd/raw/StaticModule.java
+++ b/java/com/google/gerrit/httpd/raw/StaticModule.java
@@ -79,6 +79,7 @@
           "/dashboard/*",
           "/groups/self",
           "/settings/*",
+          "/topic/*",
           "/Documentation/q/*");
 
   /**
@@ -93,7 +94,8 @@
           "/elements/*",
           "/fonts/*",
           "/scripts/*",
-          "/styles/*");
+          "/styles/*",
+          "/workers/*");
 
   private static final String DOC_SERVLET = "DocServlet";
   private static final String FAVICON_SERVLET = "FaviconServlet";
diff --git a/java/com/google/gerrit/httpd/restapi/RestApiServlet.java b/java/com/google/gerrit/httpd/restapi/RestApiServlet.java
index d981a45..543e794 100644
--- a/java/com/google/gerrit/httpd/restapi/RestApiServlet.java
+++ b/java/com/google/gerrit/httpd/restapi/RestApiServlet.java
@@ -825,7 +825,7 @@
       if (isRead(request)) {
         logger.atWarning().log(
             "request %s performed a ref update %s although the request is a READ request",
-            request.getRequestURL().toString(), refUpdateFormat);
+            request.getRequestURL(), refUpdateFormat);
       }
       response.addHeader(X_GERRIT_UPDATED_REF, refUpdateFormat);
     }
@@ -1714,7 +1714,7 @@
   private static List<IdString> splitPath(HttpServletRequest req) {
     String path = RequestUtil.getEncodedPathInfo(req);
     if (Strings.isNullOrEmpty(path)) {
-      return Collections.emptyList();
+      return new ArrayList<>();
     }
     List<IdString> out = new ArrayList<>();
     for (String p : Splitter.on('/').split(path)) {
diff --git a/java/com/google/gerrit/index/query/AndPredicate.java b/java/com/google/gerrit/index/query/AndPredicate.java
index 098bccb..23ae312 100644
--- a/java/com/google/gerrit/index/query/AndPredicate.java
+++ b/java/com/google/gerrit/index/query/AndPredicate.java
@@ -109,6 +109,8 @@
     return getChild(0).hashCode() * 31 + getChild(1).hashCode();
   }
 
+  // Suppress the EqualsGetClass warning as this is legacy code.
+  @SuppressWarnings("EqualsGetClass")
   @Override
   public boolean equals(Object other) {
     if (other == null) {
diff --git a/java/com/google/gerrit/index/query/DataSource.java b/java/com/google/gerrit/index/query/DataSource.java
index eb04099..3b83478 100644
--- a/java/com/google/gerrit/index/query/DataSource.java
+++ b/java/com/google/gerrit/index/query/DataSource.java
@@ -15,9 +15,9 @@
 package com.google.gerrit.index.query;
 
 public interface DataSource<T> extends HasCardinality {
-  /** Returns read from the database and return the results. */
+  /** Returns read from the index and return the results. */
   ResultSet<T> read();
 
-  /** Returns read from the database and return the raw results. */
+  /** Returns read from the index and return the raw results. */
   ResultSet<FieldBundle> readRaw();
 }
diff --git a/java/com/google/gerrit/index/query/IndexPredicate.java b/java/com/google/gerrit/index/query/IndexPredicate.java
index 18d7fbc..b65fb96 100644
--- a/java/com/google/gerrit/index/query/IndexPredicate.java
+++ b/java/com/google/gerrit/index/query/IndexPredicate.java
@@ -35,7 +35,7 @@
    * complexity was reduced to the bare minimum at the cost of small discrepancies to the Unicode
    * spec.
    */
-  private static final Splitter FULL_TEXT_SPLITTER = Splitter.on(CharMatcher.anyOf(" ,.-:\\/_\n"));
+  private static final Splitter FULL_TEXT_SPLITTER = Splitter.on(CharMatcher.anyOf(" ,.-:\\/_=\n"));
 
   private final FieldDef<I, ?> def;
 
diff --git a/java/com/google/gerrit/index/query/IndexedQuery.java b/java/com/google/gerrit/index/query/IndexedQuery.java
index df14e29..ee25ef9 100644
--- a/java/com/google/gerrit/index/query/IndexedQuery.java
+++ b/java/com/google/gerrit/index/query/IndexedQuery.java
@@ -108,6 +108,8 @@
     return pred.hashCode();
   }
 
+  // Suppress the EqualsGetClass warning as this is legacy code.
+  @SuppressWarnings("EqualsGetClass")
   @Override
   public boolean equals(Object other) {
     if (other == null || getClass() != other.getClass()) {
diff --git a/java/com/google/gerrit/index/query/IntPredicate.java b/java/com/google/gerrit/index/query/IntPredicate.java
index 16e59e7..a98e0b1 100644
--- a/java/com/google/gerrit/index/query/IntPredicate.java
+++ b/java/com/google/gerrit/index/query/IntPredicate.java
@@ -37,6 +37,8 @@
     return getOperator().hashCode() * 31 + intValue;
   }
 
+  // Suppress the EqualsGetClass warning as this is legacy code.
+  @SuppressWarnings("EqualsGetClass")
   @Override
   public boolean equals(Object other) {
     if (other == null) {
diff --git a/java/com/google/gerrit/index/query/NotPredicate.java b/java/com/google/gerrit/index/query/NotPredicate.java
index 14cb740..fa8e01b 100644
--- a/java/com/google/gerrit/index/query/NotPredicate.java
+++ b/java/com/google/gerrit/index/query/NotPredicate.java
@@ -21,10 +21,10 @@
 import java.util.List;
 
 /** Negates the result of another predicate. */
-public class NotPredicate<T> extends Predicate<T> implements Matchable<T> {
+public final class NotPredicate<T> extends Predicate<T> implements Matchable<T> {
   private final Predicate<T> that;
 
-  protected NotPredicate(Predicate<T> that) {
+  NotPredicate(Predicate<T> that) {
     if (that instanceof NotPredicate) {
       throw new IllegalArgumentException("Double negation unsupported");
     }
@@ -87,7 +87,7 @@
     if (other == null) {
       return false;
     }
-    return getClass() == other.getClass()
+    return other instanceof NotPredicate
         && getChildren().equals(((Predicate<?>) other).getChildren());
   }
 
diff --git a/java/com/google/gerrit/index/query/OperatorPredicate.java b/java/com/google/gerrit/index/query/OperatorPredicate.java
index 368ee24..ea7717f 100644
--- a/java/com/google/gerrit/index/query/OperatorPredicate.java
+++ b/java/com/google/gerrit/index/query/OperatorPredicate.java
@@ -47,6 +47,8 @@
     return getOperator().hashCode() * 31 + getValue().hashCode();
   }
 
+  // Suppress the EqualsGetClass warning as this is legacy code.
+  @SuppressWarnings("EqualsGetClass")
   @Override
   public boolean equals(Object other) {
     if (other == null) {
diff --git a/java/com/google/gerrit/index/query/OrPredicate.java b/java/com/google/gerrit/index/query/OrPredicate.java
index 9bc3769..1c31af3 100644
--- a/java/com/google/gerrit/index/query/OrPredicate.java
+++ b/java/com/google/gerrit/index/query/OrPredicate.java
@@ -105,6 +105,8 @@
     return getChild(0).hashCode() * 31 + getChild(1).hashCode();
   }
 
+  // Suppress the EqualsGetClass warning as this is legacy code.
+  @SuppressWarnings("EqualsGetClass")
   @Override
   public boolean equals(Object other) {
     if (other == null) {
diff --git a/java/com/google/gerrit/index/query/Predicate.java b/java/com/google/gerrit/index/query/Predicate.java
index 9dc7689..e251b00 100644
--- a/java/com/google/gerrit/index/query/Predicate.java
+++ b/java/com/google/gerrit/index/query/Predicate.java
@@ -18,10 +18,10 @@
 import static com.google.common.base.Preconditions.checkState;
 
 import com.google.common.collect.Iterables;
+import java.util.ArrayDeque;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
-import java.util.LinkedList;
 import java.util.List;
 import java.util.Queue;
 
@@ -152,7 +152,7 @@
   /** Returns a list of this predicate and all its descendants. */
   public List<Predicate<T>> getFlattenedPredicateList() {
     List<Predicate<T>> result = new ArrayList<>();
-    Queue<Predicate<T>> queue = new LinkedList<>();
+    Queue<Predicate<T>> queue = new ArrayDeque<>();
     queue.add(this);
     while (!queue.isEmpty()) {
       Predicate<T> current = queue.poll();
diff --git a/java/com/google/gerrit/index/query/QueryBuilder.java b/java/com/google/gerrit/index/query/QueryBuilder.java
index ffa7ce4..987c7d3 100644
--- a/java/com/google/gerrit/index/query/QueryBuilder.java
+++ b/java/com/google/gerrit/index/query/QueryBuilder.java
@@ -31,6 +31,7 @@
 import com.google.common.base.CharMatcher;
 import com.google.common.base.MoreObjects;
 import com.google.common.base.Strings;
+import com.google.common.base.Throwables;
 import com.google.common.collect.ImmutableMap;
 import com.google.gerrit.common.Nullable;
 import com.google.gerrit.extensions.registration.DynamicMap;
@@ -46,6 +47,7 @@
 import java.util.Collections;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 import org.antlr.runtime.CharStream;
 import org.antlr.runtime.CommonToken;
 import org.antlr.runtime.tree.CommonTree;
@@ -364,7 +366,7 @@
    * @throws QueryParseException the parser does not recognize this value.
    */
   protected Predicate<T> defaultField(String value) throws QueryParseException {
-    throw error("Unsupported query:" + value);
+    throw error("Unsupported query: " + value);
   }
 
   private List<Predicate<T>> children(Tree r) throws QueryParseException, IllegalArgumentException {
@@ -416,8 +418,13 @@
       } catch (RuntimeException | IllegalAccessException e) {
         throw error("Error in operator " + name + ":" + value, e);
       } catch (InvocationTargetException e) {
-        if (e.getCause() instanceof QueryParseException) {
-          throw (QueryParseException) e.getCause();
+        Optional<QueryParseException> queryParseException =
+            Throwables.getCausalChain(e).stream()
+                .filter(QueryParseException.class::isInstance)
+                .map(QueryParseException.class::cast)
+                .findAny();
+        if (queryParseException.isPresent()) {
+          throw queryParseException.get();
         }
         throw error("Error in operator " + name + ":" + value, e.getCause());
       }
diff --git a/java/com/google/gerrit/index/query/QueryProcessor.java b/java/com/google/gerrit/index/query/QueryProcessor.java
index ec90d21..21d4c2e 100644
--- a/java/com/google/gerrit/index/query/QueryProcessor.java
+++ b/java/com/google/gerrit/index/query/QueryProcessor.java
@@ -267,7 +267,7 @@
                 pageSizeMultiplier,
                 limit,
                 getRequestedFields());
-        logger.atFine().log("Query options: " + opts);
+        logger.atFine().log("Query options: %s", opts);
         Predicate<T> pred = rewriter.rewrite(q, opts);
         if (enforceVisibility) {
           pred = enforceVisibility(pred);
diff --git a/java/com/google/gerrit/index/query/TimestampRangePredicate.java b/java/com/google/gerrit/index/query/TimestampRangePredicate.java
index 42f8aa8..29d6f22 100644
--- a/java/com/google/gerrit/index/query/TimestampRangePredicate.java
+++ b/java/com/google/gerrit/index/query/TimestampRangePredicate.java
@@ -17,13 +17,13 @@
 import com.google.gerrit.index.FieldDef;
 import com.google.gerrit.json.JavaSqlTimestampHelper;
 import java.sql.Timestamp;
-import java.util.Date;
+import java.time.Instant;
 
 // TODO: Migrate this to IntegerRangePredicate
 public abstract class TimestampRangePredicate<I> extends IndexPredicate<I> {
-  protected static Timestamp parse(String value) throws QueryParseException {
+  protected static Instant parse(String value) throws QueryParseException {
     try {
-      return JavaSqlTimestampHelper.parseTimestamp(value);
+      return JavaSqlTimestampHelper.parseTimestamp(value).toInstant();
     } catch (IllegalArgumentException e) {
       // parseTimestamp's errors are specific and helpful, so preserve them.
       throw new QueryParseException(e.getMessage(), e);
@@ -38,7 +38,7 @@
     return (Timestamp) this.getField().get(object);
   }
 
-  public abstract Date getMinTimestamp();
+  public abstract Instant getMinTimestamp();
 
-  public abstract Date getMaxTimestamp();
+  public abstract Instant getMaxTimestamp();
 }
diff --git a/java/com/google/gerrit/index/testing/AbstractFakeIndex.java b/java/com/google/gerrit/index/testing/AbstractFakeIndex.java
index 4197c64..4241828 100644
--- a/java/com/google/gerrit/index/testing/AbstractFakeIndex.java
+++ b/java/com/google/gerrit/index/testing/AbstractFakeIndex.java
@@ -48,7 +48,7 @@
 import com.google.gerrit.server.query.change.ChangeData;
 import com.google.inject.Inject;
 import com.google.inject.assistedinject.Assisted;
-import java.sql.Timestamp;
+import java.time.Instant;
 import java.util.Comparator;
 import java.util.HashMap;
 import java.util.List;
@@ -142,7 +142,7 @@
       }
       queryCount++;
     }
-    return new DataSource<V>() {
+    return new DataSource<>() {
       @Override
       public int getCardinality() {
         return results.size();
@@ -241,7 +241,7 @@
       Comparator<ChangeData> lastUpdated =
           Comparator.comparing(cd -> cd.change().getLastUpdatedOn());
       Comparator<ChangeData> merged =
-          Comparator.comparing(cd -> cd.getMergedOn().orElse(new Timestamp(0)));
+          Comparator.comparing(cd -> cd.getMergedOn().orElse(Instant.EPOCH));
       Comparator<ChangeData> id = Comparator.comparing(cd -> cd.getId().get());
       return lastUpdated.thenComparing(merged).thenComparing(id).reversed();
     }
diff --git a/java/com/google/gerrit/json/BUILD b/java/com/google/gerrit/json/BUILD
index d9cec45..7b2fe2f 100644
--- a/java/com/google/gerrit/json/BUILD
+++ b/java/com/google/gerrit/json/BUILD
@@ -5,6 +5,10 @@
     srcs = glob(["*.java"]),
     visibility = ["//visibility:public"],
     deps = [
+        "//java/com/google/gerrit/common:annotations",
+        "//java/com/google/gerrit/entities",
         "//lib:gson",
+        "//lib:guava",
+        "//lib/guice",
     ],
 )
diff --git a/java/com/google/gerrit/json/JavaSqlTimestampHelper.java b/java/com/google/gerrit/json/JavaSqlTimestampHelper.java
index b59cbd0d..35429f1 100644
--- a/java/com/google/gerrit/json/JavaSqlTimestampHelper.java
+++ b/java/com/google/gerrit/json/JavaSqlTimestampHelper.java
@@ -14,11 +14,19 @@
 
 package com.google.gerrit.json;
 
+import com.google.common.base.Splitter;
 import java.sql.Timestamp;
-import java.util.Date;
+import java.util.Calendar;
+import java.util.List;
+import java.util.TimeZone;
 
 /** Utility to parse Timestamp from a string. */
 public class JavaSqlTimestampHelper {
+
+  private static final Splitter TIMESTAMP_SPLITTER = Splitter.on(" ");
+  private static final Splitter DATE_SPLITTER = Splitter.on("-");
+  private static final Splitter TIME_SPLITTER = Splitter.on(":");
+
   /**
    * Parse a string into a timestamp.
    *
@@ -31,22 +39,22 @@
    * @return resulting timestamp.
    */
   public static Timestamp parseTimestamp(String s) {
-    String[] components = s.split(" ");
-    if (components.length < 1 || components.length > 3) {
+    List<String> components = TIMESTAMP_SPLITTER.splitToList(s);
+    if (components.size() < 1 || components.size() > 3) {
       throw new IllegalArgumentException("Expected date and optional time: " + s);
     }
-    String date = components[0];
-    String time = components.length >= 2 ? components[1] : null;
-    int off = components.length == 3 ? parseTimeZone(components[2]) : 0;
-    String[] dSplit = date.split("-");
-    if (dSplit.length != 3) {
+    String date = components.get(0);
+    String time = components.size() >= 2 ? components.get(1) : null;
+    int off = components.size() == 3 ? parseTimeZone(components.get(2)) : 0;
+    List<String> dSplit = DATE_SPLITTER.splitToList(date);
+    if (dSplit.size() != 3) {
       throw new IllegalArgumentException("Invalid date format: " + date);
     }
     int yy, mm, dd;
     try {
-      yy = Integer.parseInt(dSplit[0]) - 1900;
-      mm = Integer.parseInt(dSplit[1]) - 1;
-      dd = Integer.parseInt(dSplit[2]);
+      yy = Integer.parseInt(dSplit.get(0));
+      mm = Integer.parseInt(dSplit.get(1)) - 1;
+      dd = Integer.parseInt(dSplit.get(2));
     } catch (NumberFormatException e) {
       throw new IllegalArgumentException("Invalid date format: " + date, e);
     }
@@ -64,13 +72,13 @@
           t = time;
           f = 0;
         }
-        String[] tSplit = t.split(":");
-        if (tSplit.length != 3) {
+        List<String> tSplit = TIME_SPLITTER.splitToList(t);
+        if (tSplit.size() != 3) {
           throw new IllegalArgumentException("Invalid time format: " + time);
         }
-        hh = Integer.parseInt(tSplit[0]);
-        mi = Integer.parseInt(tSplit[1]);
-        ss = Integer.parseInt(tSplit[2]);
+        hh = Integer.parseInt(tSplit.get(0));
+        mi = Integer.parseInt(tSplit.get(1));
+        ss = Integer.parseInt(tSplit.get(2));
         ns = (int) Math.round(f * 1e9);
       } catch (NumberFormatException e) {
         throw new IllegalArgumentException("Invalid time format: " + time, e);
@@ -81,8 +89,9 @@
       ss = 0;
       ns = 0;
     }
-    @SuppressWarnings("deprecation")
-    Timestamp result = new Timestamp(Date.UTC(yy, mm, dd, hh, mi, ss) - off);
+    Calendar calendar = Calendar.getInstance(TimeZone.getTimeZone("UTC"));
+    calendar.set(yy, mm, dd, hh, mi, ss);
+    Timestamp result = new Timestamp(calendar.toInstant().toEpochMilli() - off);
     result.setNanos(ns);
     return result;
   }
diff --git a/java/com/google/gerrit/json/OptionalSubmitRequirementExpressionResultAdapterFactory.java b/java/com/google/gerrit/json/OptionalSubmitRequirementExpressionResultAdapterFactory.java
new file mode 100644
index 0000000..d35b8fb
--- /dev/null
+++ b/java/com/google/gerrit/json/OptionalSubmitRequirementExpressionResultAdapterFactory.java
@@ -0,0 +1,150 @@
+// Copyright (C) 2022 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.json;
+
+import com.google.gerrit.common.Nullable;
+import com.google.gerrit.entities.SubmitRequirementExpressionResult;
+import com.google.gerrit.entities.SubmitRequirementResult;
+import com.google.gson.Gson;
+import com.google.gson.JsonElement;
+import com.google.gson.JsonParser;
+import com.google.gson.TypeAdapter;
+import com.google.gson.TypeAdapterFactory;
+import com.google.gson.reflect.TypeToken;
+import com.google.gson.stream.JsonReader;
+import com.google.gson.stream.JsonWriter;
+import com.google.inject.TypeLiteral;
+import java.io.IOException;
+import java.util.Optional;
+
+/**
+ * A {@code TypeAdapterFactory} for Optional {@code SubmitRequirementExpressionResult}.
+ *
+ * <p>{@link SubmitRequirementResult#submittabilityExpressionResult} was previously serialized as a
+ * mandatory field, but was later on migrated to an optional field. The server needs to handle
+ * deserializing of both formats.
+ */
+public class OptionalSubmitRequirementExpressionResultAdapterFactory implements TypeAdapterFactory {
+
+  private static final TypeToken<?> OPTIONAL_SR_EXPRESSION_RESULT_TOKEN =
+      TypeToken.get(new TypeLiteral<Optional<SubmitRequirementExpressionResult>>() {}.getType());
+
+  private static final TypeToken<?> SR_EXPRESSION_RESULT_TOKEN =
+      TypeToken.get(SubmitRequirementExpressionResult.class);
+
+  @SuppressWarnings({"unchecked"})
+  @Override
+  public <T> TypeAdapter<T> create(Gson gson, TypeToken<T> typeToken) {
+    if (typeToken.equals(OPTIONAL_SR_EXPRESSION_RESULT_TOKEN)) {
+      return (TypeAdapter<T>)
+          new OptionalSubmitRequirementExpressionResultTypeAdapter(
+              SubmitRequirementExpressionResult.typeAdapter(gson));
+    } else if (typeToken.equals(SR_EXPRESSION_RESULT_TOKEN)) {
+      return (TypeAdapter<T>)
+          new SubmitRequirementExpressionResultTypeAdapter(
+              SubmitRequirementExpressionResult.typeAdapter(gson));
+    }
+    return null;
+  }
+
+  /**
+   * Reads json representation of either {@code Optional<SubmitRequirementExpressionResult>} or
+   * {@code SubmitRequirementExpressionResult}, converting it to {@code Nullable} {@code
+   * SubmitRequirementExpressionResult}.
+   */
+  @Nullable
+  private static SubmitRequirementExpressionResult readOptionalOrMandatory(
+      TypeAdapter<SubmitRequirementExpressionResult> submitRequirementExpressionResultAdapter,
+      JsonReader in) {
+    JsonElement parsed = JsonParser.parseReader(in);
+    if (parsed == null) {
+      return null;
+    }
+    // If it does not have 'value' field, then it was serialized as
+    // SubmitRequirementExpressionResult directly
+    if (parsed.getAsJsonObject().has("value")) {
+      parsed = parsed.getAsJsonObject().get("value");
+    }
+    if (parsed == null || parsed.isJsonNull() || parsed.getAsJsonObject().entrySet().isEmpty()) {
+      return null;
+    }
+    return submitRequirementExpressionResultAdapter.fromJsonTree(parsed);
+  }
+
+  /**
+   * A {@code TypeAdapter} that provides backward compatibility for reading previously non-optional
+   * {@code SubmitRequirementExpressionResult} field.
+   */
+  private static class OptionalSubmitRequirementExpressionResultTypeAdapter
+      extends TypeAdapter<Optional<SubmitRequirementExpressionResult>> {
+
+    private final TypeAdapter<SubmitRequirementExpressionResult>
+        submitRequirementExpressionResultAdapter;
+
+    public OptionalSubmitRequirementExpressionResultTypeAdapter(
+        TypeAdapter<SubmitRequirementExpressionResult> submitRequirementResultAdapter) {
+      this.submitRequirementExpressionResultAdapter = submitRequirementResultAdapter;
+    }
+
+    @Override
+    public Optional<SubmitRequirementExpressionResult> read(JsonReader in) throws IOException {
+      return Optional.ofNullable(
+          readOptionalOrMandatory(submitRequirementExpressionResultAdapter, in));
+    }
+
+    @Override
+    public void write(JsonWriter out, Optional<SubmitRequirementExpressionResult> value)
+        throws IOException {
+      // Serialize the field using the same format used by the AutoValue's default Gson serializer.
+      out.beginObject();
+      out.name("value");
+      if (value.isPresent()) {
+        out.jsonValue(submitRequirementExpressionResultAdapter.toJson(value.get()));
+      } else {
+        out.nullValue();
+      }
+      out.endObject();
+    }
+  }
+
+  /**
+   * A {@code TypeAdapter} that provides forward compatibility for reading the optional {@code
+   * SubmitRequirementExpressionResult} field.
+   *
+   * <p>TODO(mariasavtchouk): Remove once updated to read the new format only.
+   */
+  private static class SubmitRequirementExpressionResultTypeAdapter
+      extends TypeAdapter<SubmitRequirementExpressionResult> {
+
+    private final TypeAdapter<SubmitRequirementExpressionResult>
+        submitRequirementExpressionResultAdapter;
+
+    public SubmitRequirementExpressionResultTypeAdapter(
+        TypeAdapter<SubmitRequirementExpressionResult> submitRequirementResultAdapter) {
+      this.submitRequirementExpressionResultAdapter = submitRequirementResultAdapter;
+    }
+
+    @Override
+    public SubmitRequirementExpressionResult read(JsonReader in) throws IOException {
+      return readOptionalOrMandatory(submitRequirementExpressionResultAdapter, in);
+    }
+
+    @Override
+    public void write(JsonWriter out, SubmitRequirementExpressionResult value) throws IOException {
+      // Serialize the field using the same format used by the AutoValue's default Gson serializer.
+      out.jsonValue(submitRequirementExpressionResultAdapter.toJson(value));
+    }
+  }
+}
diff --git a/java/com/google/gerrit/json/OptionalTypeAdapter.java b/java/com/google/gerrit/json/OptionalTypeAdapter.java
new file mode 100644
index 0000000..9bfa72d
--- /dev/null
+++ b/java/com/google/gerrit/json/OptionalTypeAdapter.java
@@ -0,0 +1,69 @@
+// Copyright (C) 2022 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.json;
+
+import com.google.gson.JsonDeserializationContext;
+import com.google.gson.JsonDeserializer;
+import com.google.gson.JsonElement;
+import com.google.gson.JsonNull;
+import com.google.gson.JsonObject;
+import com.google.gson.JsonParseException;
+import com.google.gson.JsonSerializationContext;
+import com.google.gson.JsonSerializer;
+import com.google.inject.TypeLiteral;
+import java.lang.reflect.ParameterizedType;
+import java.lang.reflect.Type;
+import java.util.Optional;
+
+public class OptionalTypeAdapter
+    implements JsonSerializer<Optional<?>>, JsonDeserializer<Optional<?>> {
+
+  private static final String VALUE = "value";
+
+  @Override
+  public JsonElement serialize(Optional<?> src, Type typeOfSrc, JsonSerializationContext context) {
+    Optional<?> optional = src == null ? Optional.empty() : src;
+    JsonObject json = new JsonObject();
+    json.add(VALUE, optional.map(context::serialize).orElse(JsonNull.INSTANCE));
+    return json;
+  }
+
+  @Override
+  public Optional<?> deserialize(JsonElement json, Type typeOfT, JsonDeserializationContext context)
+      throws JsonParseException {
+    if (!json.getAsJsonObject().has(VALUE)) {
+      return Optional.empty();
+    }
+
+    JsonElement value = json.getAsJsonObject().get(VALUE);
+    if (value == null || value.isJsonNull()) {
+      return Optional.empty();
+    }
+
+    // handle the situation when one uses Optional without type parameter which is an equivalent of
+    // <?> type
+    ParameterizedType parameterizedType =
+        (ParameterizedType) new TypeLiteral<Optional<?>>() {}.getType();
+    if (typeOfT instanceof ParameterizedType) {
+      parameterizedType = (ParameterizedType) typeOfT;
+      if (parameterizedType.getActualTypeArguments().length != 1) {
+        throw new JsonParseException("Expected one parameter type in Optional.");
+      }
+    }
+
+    Type optionalOf = parameterizedType.getActualTypeArguments()[0];
+    return Optional.of(context.deserialize(value, optionalOf));
+  }
+}
diff --git a/java/com/google/gerrit/launcher/GerritLauncher.java b/java/com/google/gerrit/launcher/GerritLauncher.java
index 1999270..a190ebf 100644
--- a/java/com/google/gerrit/launcher/GerritLauncher.java
+++ b/java/com/google/gerrit/launcher/GerritLauncher.java
@@ -41,12 +41,12 @@
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
-import java.util.Enumeration;
 import java.util.HashMap;
+import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
+import java.util.NavigableMap;
 import java.util.Properties;
-import java.util.SortedMap;
 import java.util.TreeMap;
 import java.util.jar.Attributes;
 import java.util.jar.JarFile;
@@ -266,11 +266,11 @@
       throw e;
     }
 
-    final SortedMap<String, URL> jars = new TreeMap<>();
+    final NavigableMap<String, URL> jars = new TreeMap<>();
     try (ZipFile zf = new ZipFile(path)) {
-      final Enumeration<? extends ZipEntry> e = zf.entries();
-      while (e.hasMoreElements()) {
-        final ZipEntry ze = e.nextElement();
+      Iterator<? extends ZipEntry> zipEntryIt = zf.stream().iterator();
+      while (zipEntryIt.hasNext()) {
+        final ZipEntry ze = zipEntryIt.next();
         if (ze.isDirectory()) {
           continue;
         }
@@ -310,7 +310,7 @@
     return URLClassLoader.newInstance(jars.values().toArray(new URL[jars.size()]), parent);
   }
 
-  private static void extractJar(ZipFile zf, ZipEntry ze, SortedMap<String, URL> jars)
+  private static void extractJar(ZipFile zf, ZipEntry ze, NavigableMap<String, URL> jars)
       throws IOException {
     File tmp = createTempFile(safeName(ze), ".jar");
     try (OutputStream out = Files.newOutputStream(tmp.toPath());
@@ -326,8 +326,8 @@
     jars.put(name.substring(name.lastIndexOf('/')), tmp.toURI().toURL());
   }
 
-  private static void move(SortedMap<String, URL> jars, String prefix, List<URL> extapi) {
-    SortedMap<String, URL> matches = jars.tailMap(prefix);
+  private static void move(NavigableMap<String, URL> jars, String prefix, List<URL> extapi) {
+    NavigableMap<String, URL> matches = jars.tailMap(prefix, /* inclusive= */ true);
     if (!matches.isEmpty()) {
       String first = matches.firstKey();
       if (first.startsWith(prefix)) {
diff --git a/java/com/google/gerrit/lucene/AbstractLuceneIndex.java b/java/com/google/gerrit/lucene/AbstractLuceneIndex.java
index 6cede89..586887b 100644
--- a/java/com/google/gerrit/lucene/AbstractLuceneIndex.java
+++ b/java/com/google/gerrit/lucene/AbstractLuceneIndex.java
@@ -109,6 +109,7 @@
   private final AutoFlush autoFlush;
   private ScheduledExecutorService autoCommitExecutor;
 
+  @SuppressWarnings("ThreadPriorityCheck")
   AbstractLuceneIndex(
       Schema<V> schema,
       SitePaths sitePaths,
diff --git a/java/com/google/gerrit/lucene/LuceneChangeIndex.java b/java/com/google/gerrit/lucene/LuceneChangeIndex.java
index 512804b..daa921c 100644
--- a/java/com/google/gerrit/lucene/LuceneChangeIndex.java
+++ b/java/com/google/gerrit/lucene/LuceneChangeIndex.java
@@ -399,7 +399,7 @@
       }
       ImmutableList<FieldBundle> fieldBundles =
           documents.stream().map(rawDocumentMapper).collect(toImmutableList());
-      return new ResultSet<FieldBundle>() {
+      return new ResultSet<>() {
         @Override
         public Iterator<FieldBundle> iterator() {
           return fieldBundles.iterator();
diff --git a/java/com/google/gerrit/lucene/QueryBuilder.java b/java/com/google/gerrit/lucene/QueryBuilder.java
index 7d82bf5..e1b56c6 100644
--- a/java/com/google/gerrit/lucene/QueryBuilder.java
+++ b/java/com/google/gerrit/lucene/QueryBuilder.java
@@ -33,7 +33,6 @@
 import com.google.gerrit.index.query.QueryParseException;
 import com.google.gerrit.index.query.RegexPredicate;
 import com.google.gerrit.index.query.TimestampRangePredicate;
-import java.util.Date;
 import java.util.List;
 import org.apache.lucene.analysis.Analyzer;
 import org.apache.lucene.document.IntPoint;
@@ -232,15 +231,17 @@
     if (p instanceof TimestampRangePredicate) {
       TimestampRangePredicate<V> r = (TimestampRangePredicate<V>) p;
       return longRangeQuery.get(
-          r.getField().getName(), r.getMinTimestamp().getTime(), r.getMaxTimestamp().getTime());
+          r.getField().getName(),
+          r.getMinTimestamp().toEpochMilli(),
+          r.getMaxTimestamp().toEpochMilli());
     }
     throw new QueryParseException("not a timestamp: " + p);
   }
 
   private Query notTimestamp(TimestampRangePredicate<V> r) throws QueryParseException {
-    if (r.getMinTimestamp().getTime() == 0) {
+    if (r.getMinTimestamp().toEpochMilli() == 0) {
       return longRangeQuery.get(
-          r.getField().getName(), r.getMaxTimestamp().getTime(), Long.MAX_VALUE);
+          r.getField().getName(), r.getMaxTimestamp().toEpochMilli(), Long.MAX_VALUE);
     }
     throw new QueryParseException("cannot negate: " + r);
   }
@@ -279,10 +280,6 @@
     return query;
   }
 
-  public int toIndexTimeInMinutes(Date ts) {
-    return (int) (ts.getTime() / 60000);
-  }
-
   public Schema<V> getSchema() {
     return schema;
   }
diff --git a/java/com/google/gerrit/mail/BUILD b/java/com/google/gerrit/mail/BUILD
index 59d8227..0fe6c43 100644
--- a/java/com/google/gerrit/mail/BUILD
+++ b/java/com/google/gerrit/mail/BUILD
@@ -12,7 +12,6 @@
         "//lib/auto:auto-value-annotations",
         "//lib/flogger:api",
         "//lib/jsoup",
-        "//lib/log:log4j",
         "//lib/mime4j:core",
         "//lib/mime4j:dom",
     ],
diff --git a/java/com/google/gerrit/mail/RawMailParser.java b/java/com/google/gerrit/mail/RawMailParser.java
index 213cc3f..929e9f9 100644
--- a/java/com/google/gerrit/mail/RawMailParser.java
+++ b/java/com/google/gerrit/mail/RawMailParser.java
@@ -25,6 +25,7 @@
 import java.io.ByteArrayInputStream;
 import java.io.IOException;
 import java.io.InputStreamReader;
+import java.time.Instant;
 import org.apache.james.mime4j.MimeException;
 import org.apache.james.mime4j.dom.Entity;
 import org.apache.james.mime4j.dom.Message;
@@ -66,7 +67,9 @@
       messageBuilder.subject(mimeMessage.getSubject());
     }
     if (mimeMessage.getDate() != null) {
-      messageBuilder.dateReceived(mimeMessage.getDate().toInstant());
+      @SuppressWarnings("JdkObsolete")
+      Instant mimeMessageInstant = mimeMessage.getDate().toInstant();
+      messageBuilder.dateReceived(mimeMessageInstant);
     }
 
     // Add From, To and Cc
diff --git a/java/com/google/gerrit/metrics/DisabledMetricMaker.java b/java/com/google/gerrit/metrics/DisabledMetricMaker.java
index 1fb8c57..234378b 100644
--- a/java/com/google/gerrit/metrics/DisabledMetricMaker.java
+++ b/java/com/google/gerrit/metrics/DisabledMetricMaker.java
@@ -33,7 +33,7 @@
 
   @Override
   public <F1> Counter1<F1> newCounter(String name, Description desc, Field<F1> field1) {
-    return new Counter1<F1>() {
+    return new Counter1<>() {
       @Override
       public void incrementBy(F1 field1, long value) {}
 
@@ -45,7 +45,7 @@
   @Override
   public <F1, F2> Counter2<F1, F2> newCounter(
       String name, Description desc, Field<F1> field1, Field<F2> field2) {
-    return new Counter2<F1, F2>() {
+    return new Counter2<>() {
       @Override
       public void incrementBy(F1 field1, F2 field2, long value) {}
 
@@ -57,7 +57,7 @@
   @Override
   public <F1, F2, F3> Counter3<F1, F2, F3> newCounter(
       String name, Description desc, Field<F1> field1, Field<F2> field2, Field<F3> field3) {
-    return new Counter3<F1, F2, F3>() {
+    return new Counter3<>() {
       @Override
       public void incrementBy(F1 field1, F2 field2, F3 field3, long value) {}
 
@@ -79,7 +79,7 @@
 
   @Override
   public <F1> Timer1<F1> newTimer(String name, Description desc, Field<F1> field1) {
-    return new Timer1<F1>(name, field1) {
+    return new Timer1<>(name, field1) {
       @Override
       protected void doRecord(F1 field1, long value, TimeUnit unit) {}
 
@@ -91,7 +91,7 @@
   @Override
   public <F1, F2> Timer2<F1, F2> newTimer(
       String name, Description desc, Field<F1> field1, Field<F2> field2) {
-    return new Timer2<F1, F2>(name, field1, field2) {
+    return new Timer2<>(name, field1, field2) {
       @Override
       protected void doRecord(F1 field1, F2 field2, long value, TimeUnit unit) {}
 
@@ -103,7 +103,7 @@
   @Override
   public <F1, F2, F3> Timer3<F1, F2, F3> newTimer(
       String name, Description desc, Field<F1> field1, Field<F2> field2, Field<F3> field3) {
-    return new Timer3<F1, F2, F3>(name, field1, field2, field3) {
+    return new Timer3<>(name, field1, field2, field3) {
       @Override
       protected void doRecord(F1 field1, F2 field2, F3 field3, long value, TimeUnit unit) {}
 
@@ -125,7 +125,7 @@
 
   @Override
   public <F1> Histogram1<F1> newHistogram(String name, Description desc, Field<F1> field1) {
-    return new Histogram1<F1>() {
+    return new Histogram1<>() {
       @Override
       public void record(F1 field1, long value) {}
 
@@ -137,7 +137,7 @@
   @Override
   public <F1, F2> Histogram2<F1, F2> newHistogram(
       String name, Description desc, Field<F1> field1, Field<F2> field2) {
-    return new Histogram2<F1, F2>() {
+    return new Histogram2<>() {
       @Override
       public void record(F1 field1, F2 field2, long value) {}
 
@@ -149,7 +149,7 @@
   @Override
   public <F1, F2, F3> Histogram3<F1, F2, F3> newHistogram(
       String name, Description desc, Field<F1> field1, Field<F2> field2, Field<F3> field3) {
-    return new Histogram3<F1, F2, F3>() {
+    return new Histogram3<>() {
       @Override
       public void record(F1 field1, F2 field2, F3 field3, long value) {}
 
@@ -161,7 +161,7 @@
   @Override
   public <V> CallbackMetric0<V> newCallbackMetric(
       String name, Class<V> valueClass, Description desc) {
-    return new CallbackMetric0<V>() {
+    return new CallbackMetric0<>() {
       @Override
       public void set(V value) {}
 
@@ -173,7 +173,7 @@
   @Override
   public <F1, V> CallbackMetric1<F1, V> newCallbackMetric(
       String name, Class<V> valueClass, Description desc, Field<F1> field1) {
-    return new CallbackMetric1<F1, V>() {
+    return new CallbackMetric1<>() {
       @Override
       public void set(F1 field1, V value) {}
 
diff --git a/java/com/google/gerrit/metrics/dropwizard/CounterImpl1.java b/java/com/google/gerrit/metrics/dropwizard/CounterImpl1.java
index 0e554a8..92aeb4c 100644
--- a/java/com/google/gerrit/metrics/dropwizard/CounterImpl1.java
+++ b/java/com/google/gerrit/metrics/dropwizard/CounterImpl1.java
@@ -26,7 +26,7 @@
   }
 
   Counter1<F1> counter() {
-    return new Counter1<F1>() {
+    return new Counter1<>() {
       @Override
       public void incrementBy(F1 field1, long value) {
         total.incrementBy(value);
diff --git a/java/com/google/gerrit/metrics/dropwizard/CounterImplN.java b/java/com/google/gerrit/metrics/dropwizard/CounterImplN.java
index 07afc2a..e9199d9 100644
--- a/java/com/google/gerrit/metrics/dropwizard/CounterImplN.java
+++ b/java/com/google/gerrit/metrics/dropwizard/CounterImplN.java
@@ -29,7 +29,7 @@
   }
 
   <F1, F2> Counter2<F1, F2> counter2() {
-    return new Counter2<F1, F2>() {
+    return new Counter2<>() {
       @Override
       public void incrementBy(F1 field1, F2 field2, long value) {
         total.incrementBy(value);
@@ -44,7 +44,7 @@
   }
 
   <F1, F2, F3> Counter3<F1, F2, F3> counter3() {
-    return new Counter3<F1, F2, F3>() {
+    return new Counter3<>() {
       @Override
       public void incrementBy(F1 field1, F2 field2, F3 field3, long value) {
         total.incrementBy(value);
diff --git a/java/com/google/gerrit/metrics/dropwizard/HistogramImpl1.java b/java/com/google/gerrit/metrics/dropwizard/HistogramImpl1.java
index 4578db1..91e36b9 100644
--- a/java/com/google/gerrit/metrics/dropwizard/HistogramImpl1.java
+++ b/java/com/google/gerrit/metrics/dropwizard/HistogramImpl1.java
@@ -26,7 +26,7 @@
   }
 
   Histogram1<F1> histogram1() {
-    return new Histogram1<F1>() {
+    return new Histogram1<>() {
       @Override
       public void record(F1 field1, long value) {
         total.record(value);
diff --git a/java/com/google/gerrit/metrics/dropwizard/HistogramImplN.java b/java/com/google/gerrit/metrics/dropwizard/HistogramImplN.java
index 446590c..2caa4c5 100644
--- a/java/com/google/gerrit/metrics/dropwizard/HistogramImplN.java
+++ b/java/com/google/gerrit/metrics/dropwizard/HistogramImplN.java
@@ -29,7 +29,7 @@
   }
 
   <F1, F2> Histogram2<F1, F2> histogram2() {
-    return new Histogram2<F1, F2>() {
+    return new Histogram2<>() {
       @Override
       public void record(F1 field1, F2 field2, long value) {
         total.record(value);
@@ -44,7 +44,7 @@
   }
 
   <F1, F2, F3> Histogram3<F1, F2, F3> histogram3() {
-    return new Histogram3<F1, F2, F3>() {
+    return new Histogram3<>() {
       @Override
       public void record(F1 field1, F2 field2, F3 field3, long value) {
         total.record(value);
diff --git a/java/com/google/gerrit/metrics/dropwizard/ListMetrics.java b/java/com/google/gerrit/metrics/dropwizard/ListMetrics.java
index 7e472c9..6b17456 100644
--- a/java/com/google/gerrit/metrics/dropwizard/ListMetrics.java
+++ b/java/com/google/gerrit/metrics/dropwizard/ListMetrics.java
@@ -26,7 +26,7 @@
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;
-import java.util.SortedMap;
+import java.util.NavigableMap;
 import java.util.TreeMap;
 import org.kohsuke.args4j.Option;
 
@@ -55,7 +55,7 @@
       throws AuthException, PermissionBackendException {
     permissionBackend.currentUser().check(GlobalPermission.VIEW_CACHES);
 
-    SortedMap<String, MetricJson> out = new TreeMap<>();
+    NavigableMap<String, MetricJson> out = new TreeMap<>();
     List<String> prefixes = new ArrayList<>(query.size());
     for (String q : query) {
       if (q.endsWith("/")) {
diff --git a/java/com/google/gerrit/metrics/dropwizard/MetricResource.java b/java/com/google/gerrit/metrics/dropwizard/MetricResource.java
index 226edc7..8a6db67 100644
--- a/java/com/google/gerrit/metrics/dropwizard/MetricResource.java
+++ b/java/com/google/gerrit/metrics/dropwizard/MetricResource.java
@@ -20,8 +20,7 @@
 import com.google.inject.TypeLiteral;
 
 class MetricResource extends ConfigResource {
-  static final TypeLiteral<RestView<MetricResource>> METRIC_KIND =
-      new TypeLiteral<RestView<MetricResource>>() {};
+  static final TypeLiteral<RestView<MetricResource>> METRIC_KIND = new TypeLiteral<>() {};
 
   private final String name;
   private final Metric metric;
diff --git a/java/com/google/gerrit/metrics/dropwizard/TimerImpl1.java b/java/com/google/gerrit/metrics/dropwizard/TimerImpl1.java
index b7d535b..36b52e1 100644
--- a/java/com/google/gerrit/metrics/dropwizard/TimerImpl1.java
+++ b/java/com/google/gerrit/metrics/dropwizard/TimerImpl1.java
@@ -28,7 +28,7 @@
 
   @SuppressWarnings("unchecked")
   Timer1<F1> timer() {
-    return new Timer1<F1>(name, (Field<F1>) fields[0]) {
+    return new Timer1<>(name, (Field<F1>) fields[0]) {
       @Override
       protected void doRecord(F1 field1, long value, TimeUnit unit) {
         total.record(value, unit);
diff --git a/java/com/google/gerrit/metrics/dropwizard/TimerImplN.java b/java/com/google/gerrit/metrics/dropwizard/TimerImplN.java
index dee800e..77ce8cd 100644
--- a/java/com/google/gerrit/metrics/dropwizard/TimerImplN.java
+++ b/java/com/google/gerrit/metrics/dropwizard/TimerImplN.java
@@ -31,7 +31,7 @@
 
   @SuppressWarnings("unchecked")
   <F1, F2> Timer2<F1, F2> timer2() {
-    return new Timer2<F1, F2>(name, (Field<F1>) fields[0], (Field<F2>) fields[1]) {
+    return new Timer2<>(name, (Field<F1>) fields[0], (Field<F2>) fields[1]) {
       @Override
       protected void doRecord(F1 field1, F2 field2, long value, TimeUnit unit) {
         total.record(value, unit);
@@ -47,8 +47,7 @@
 
   @SuppressWarnings("unchecked")
   <F1, F2, F3> Timer3<F1, F2, F3> timer3() {
-    return new Timer3<F1, F2, F3>(
-        name, (Field<F1>) fields[0], (Field<F2>) fields[1], (Field<F3>) fields[2]) {
+    return new Timer3<>(name, (Field<F1>) fields[0], (Field<F2>) fields[1], (Field<F3>) fields[2]) {
       @Override
       protected void doRecord(F1 field1, F2 field2, F3 field3, long value, TimeUnit unit) {
         total.record(value, unit);
diff --git a/java/com/google/gerrit/pgm/BUILD b/java/com/google/gerrit/pgm/BUILD
index 3a1de5e..df64bc7 100644
--- a/java/com/google/gerrit/pgm/BUILD
+++ b/java/com/google/gerrit/pgm/BUILD
@@ -48,12 +48,11 @@
         "//lib:servlet-api-without-neverlink",
         "//lib/auto:auto-value",
         "//lib/auto:auto-value-annotations",
-        "//lib/commons:lang",
+        "//lib/commons:lang3",
         "//lib/flogger:api",
         "//lib/guice",
         "//lib/guice:guice-assistedinject",
         "//lib/guice:guice-servlet",
-        "//lib/log:log4j",
         "//lib/prolog:cafeteria",
         "//lib/prolog:compiler",
         "//lib/prolog:runtime",
diff --git a/java/com/google/gerrit/pgm/CopyApprovals.java b/java/com/google/gerrit/pgm/CopyApprovals.java
deleted file mode 100644
index f62d60c..0000000
--- a/java/com/google/gerrit/pgm/CopyApprovals.java
+++ /dev/null
@@ -1,138 +0,0 @@
-// Copyright (C) 2022 The Android Open Source Project
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package com.google.gerrit.pgm;
-
-import com.google.gerrit.extensions.config.FactoryModule;
-import com.google.gerrit.index.IndexType;
-import com.google.gerrit.lifecycle.LifecycleManager;
-import com.google.gerrit.lucene.LuceneIndexModule;
-import com.google.gerrit.pgm.util.BatchProgramModule;
-import com.google.gerrit.pgm.util.SiteProgram;
-import com.google.gerrit.server.LibModuleLoader;
-import com.google.gerrit.server.ModuleOverloader;
-import com.google.gerrit.server.approval.RecursiveApprovalCopier;
-import com.google.gerrit.server.change.ChangeResource;
-import com.google.gerrit.server.config.GerritServerConfig;
-import com.google.gerrit.server.index.IndexModule;
-import com.google.gerrit.server.index.options.AutoFlush;
-import com.google.gerrit.server.index.options.IsFirstInsertForEntry;
-import com.google.gerrit.server.plugins.PluginGuiceEnvironment;
-import com.google.gerrit.server.util.ReplicaUtil;
-import com.google.inject.AbstractModule;
-import com.google.inject.Inject;
-import com.google.inject.Injector;
-import com.google.inject.Key;
-import com.google.inject.Module;
-import com.google.inject.multibindings.OptionalBinder;
-import java.lang.reflect.InvocationTargetException;
-import java.lang.reflect.Method;
-import java.util.ArrayList;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
-import org.eclipse.jgit.lib.Config;
-
-public class CopyApprovals extends SiteProgram {
-
-  private Injector dbInjector;
-  private Injector sysInjector;
-  private Injector cfgInjector;
-  private Config globalConfig;
-
-  @Inject private RecursiveApprovalCopier recursiveApprovalCopier;
-
-  @Override
-  public int run() throws Exception {
-    mustHaveValidSite();
-    dbInjector = createDbInjector();
-    cfgInjector = dbInjector.createChildInjector();
-    globalConfig = dbInjector.getInstance(Key.get(Config.class, GerritServerConfig.class));
-    LifecycleManager dbManager = new LifecycleManager();
-    dbManager.add(dbInjector);
-    dbManager.start();
-
-    sysInjector = createSysInjector();
-    sysInjector.getInstance(PluginGuiceEnvironment.class).setDbCfgInjector(dbInjector, cfgInjector);
-    LifecycleManager sysManager = new LifecycleManager();
-    sysManager.add(sysInjector);
-    sysManager.start();
-
-    sysInjector.injectMembers(this);
-
-    try {
-      recursiveApprovalCopier.persistStandalone();
-      return 0;
-    } catch (Exception e) {
-      throw die(e.getMessage(), e);
-    } finally {
-      sysManager.stop();
-      dbManager.stop();
-    }
-  }
-
-  private Injector createSysInjector() {
-    Map<String, Integer> versions = new HashMap<>();
-    boolean replica = ReplicaUtil.isReplica(globalConfig);
-    List<Module> modules = new ArrayList<>();
-    Module indexModule;
-    IndexType indexType = IndexModule.getIndexType(dbInjector);
-    if (indexType.isLucene()) {
-      indexModule =
-          LuceneIndexModule.singleVersionWithExplicitVersions(
-              versions, 1, replica, AutoFlush.DISABLED);
-    } else if (indexType.isFake()) {
-      // Use Reflection so that we can omit the fake index binary in production code. Test code does
-      // compile the component in.
-      try {
-        Class<?> clazz = Class.forName("com.google.gerrit.index.testing.FakeIndexModule");
-        Method m =
-            clazz.getMethod(
-                "singleVersionWithExplicitVersions", Map.class, int.class, boolean.class);
-        indexModule = (Module) m.invoke(null, versions, 1, replica);
-      } catch (NoSuchMethodException
-          | ClassNotFoundException
-          | IllegalAccessException
-          | InvocationTargetException e) {
-        throw new IllegalStateException("can't create index", e);
-      }
-    } else {
-      throw new IllegalStateException("unsupported index.type = " + indexType);
-    }
-    modules.add(indexModule);
-    modules.add(
-        new AbstractModule() {
-          @Override
-          protected void configure() {
-            super.configure();
-            OptionalBinder.newOptionalBinder(binder(), IsFirstInsertForEntry.class)
-                .setBinding()
-                .toInstance(IsFirstInsertForEntry.YES);
-          }
-        });
-
-    modules.add(
-        new FactoryModule() {
-          @Override
-          protected void configure() {
-            factory(ChangeResource.Factory.class);
-          }
-        });
-    modules.add(new BatchProgramModule(dbInjector));
-
-    return dbInjector.createChildInjector(
-        ModuleOverloader.override(
-            modules, LibModuleLoader.loadReindexModules(cfgInjector, versions, 1, replica)));
-  }
-}
diff --git a/java/com/google/gerrit/pgm/Daemon.java b/java/com/google/gerrit/pgm/Daemon.java
index d77daa1..75891fe 100644
--- a/java/com/google/gerrit/pgm/Daemon.java
+++ b/java/com/google/gerrit/pgm/Daemon.java
@@ -493,7 +493,7 @@
           });
     }
     modules.add(new DefaultUrlFormatterModule());
-    SshSessionFactoryInitializer.init(config);
+    SshSessionFactoryInitializer.init();
     if (sshd) {
       modules.add(SshKeyCacheImpl.module());
     } else {
diff --git a/java/com/google/gerrit/pgm/JythonShell.java b/java/com/google/gerrit/pgm/JythonShell.java
index 88f7b5d..d85bdc0 100644
--- a/java/com/google/gerrit/pgm/JythonShell.java
+++ b/java/com/google/gerrit/pgm/JythonShell.java
@@ -173,7 +173,7 @@
         logger.atSevere().log("Cannot load resource %s", p);
       }
     } catch (IOException e) {
-      logger.atSevere().withCause(e).log(e.getMessage());
+      logger.atSevere().withCause(e).log("%s", e.getMessage());
     }
   }
 
diff --git a/java/com/google/gerrit/pgm/LocalUsernamesToLowerCase.java b/java/com/google/gerrit/pgm/LocalUsernamesToLowerCase.java
index f651994..b7ff1f7 100644
--- a/java/com/google/gerrit/pgm/LocalUsernamesToLowerCase.java
+++ b/java/com/google/gerrit/pgm/LocalUsernamesToLowerCase.java
@@ -38,7 +38,7 @@
 import java.util.Collection;
 import java.util.Locale;
 import java.util.Optional;
-import org.apache.commons.lang.StringUtils;
+import org.apache.commons.lang3.StringUtils;
 import org.eclipse.jgit.errors.ConfigInvalidException;
 import org.eclipse.jgit.lib.ProgressMonitor;
 import org.eclipse.jgit.lib.Repository;
diff --git a/java/com/google/gerrit/pgm/Ls.java b/java/com/google/gerrit/pgm/Ls.java
index 4211c17..4b48148 100644
--- a/java/com/google/gerrit/pgm/Ls.java
+++ b/java/com/google/gerrit/pgm/Ls.java
@@ -14,10 +14,11 @@
 
 package com.google.gerrit.pgm;
 
+import static com.google.common.collect.ImmutableList.toImmutableList;
+
 import com.google.gerrit.launcher.GerritLauncher;
 import com.google.gerrit.pgm.util.AbstractProgram;
 import java.io.IOException;
-import java.util.Enumeration;
 import java.util.zip.ZipEntry;
 import java.util.zip.ZipFile;
 
@@ -26,9 +27,7 @@
   @Override
   public int run() throws IOException {
     try (ZipFile zf = new ZipFile(GerritLauncher.getDistributionArchive())) {
-      final Enumeration<? extends ZipEntry> e = zf.entries();
-      while (e.hasMoreElements()) {
-        final ZipEntry ze = e.nextElement();
+      for (ZipEntry ze : entriesOf(zf)) {
         String name = ze.getName();
         boolean show = false;
         show |= name.startsWith("WEB-INF/");
@@ -49,4 +48,8 @@
     }
     return 0;
   }
+
+  private static Iterable<? extends ZipEntry> entriesOf(ZipFile zipFile) {
+    return zipFile.stream().collect(toImmutableList());
+  }
 }
diff --git a/java/com/google/gerrit/pgm/SwitchSecureStore.java b/java/com/google/gerrit/pgm/SwitchSecureStore.java
index 733c9d1..824a9a7 100644
--- a/java/com/google/gerrit/pgm/SwitchSecureStore.java
+++ b/java/com/google/gerrit/pgm/SwitchSecureStore.java
@@ -196,7 +196,7 @@
           return jar;
         }
       } catch (IOException e) {
-        logger.atSevere().withCause(e).log(e.getMessage());
+        logger.atSevere().withCause(e).log("%s", e.getMessage());
       }
     }
     return null;
diff --git a/java/com/google/gerrit/pgm/WarDistribution.java b/java/com/google/gerrit/pgm/WarDistribution.java
index 257fb4e..013c850 100644
--- a/java/com/google/gerrit/pgm/WarDistribution.java
+++ b/java/com/google/gerrit/pgm/WarDistribution.java
@@ -14,6 +14,7 @@
 
 package com.google.gerrit.pgm;
 
+import static com.google.common.collect.ImmutableList.toImmutableList;
 import static com.google.gerrit.pgm.init.InitPlugins.JAR;
 import static com.google.gerrit.pgm.init.InitPlugins.PLUGIN_DIR;
 
@@ -25,7 +26,6 @@
 import java.io.FileNotFoundException;
 import java.io.IOException;
 import java.io.InputStream;
-import java.util.Enumeration;
 import java.util.List;
 import java.util.zip.ZipEntry;
 import java.util.zip.ZipFile;
@@ -39,9 +39,7 @@
     File myWar = GerritLauncher.getDistributionArchive();
     if (myWar.isFile()) {
       try (ZipFile zf = new ZipFile(myWar)) {
-        Enumeration<? extends ZipEntry> e = zf.entries();
-        while (e.hasMoreElements()) {
-          ZipEntry ze = e.nextElement();
+        for (ZipEntry ze : entriesOf(zf)) {
           if (ze.isDirectory()) {
             continue;
           }
@@ -65,4 +63,8 @@
     // not yet used
     throw new UnsupportedOperationException();
   }
+
+  private static Iterable<? extends ZipEntry> entriesOf(ZipFile zipFile) {
+    return zipFile.stream().collect(toImmutableList());
+  }
 }
diff --git a/java/com/google/gerrit/pgm/init/AccountsOnInit.java b/java/com/google/gerrit/pgm/init/AccountsOnInit.java
index d9e3a6a..c56a8d9 100644
--- a/java/com/google/gerrit/pgm/init/AccountsOnInit.java
+++ b/java/com/google/gerrit/pgm/init/AccountsOnInit.java
@@ -30,6 +30,7 @@
 import java.io.File;
 import java.io.IOException;
 import java.nio.file.Path;
+import java.util.Date;
 import org.eclipse.jgit.dircache.DirCache;
 import org.eclipse.jgit.dircache.DirCacheEditor;
 import org.eclipse.jgit.dircache.DirCacheEditor.PathEdit;
@@ -60,12 +61,16 @@
     this.allUsers = allUsers.get();
   }
 
+  // TODO(issue-15517): Fix the JdkObsolete issue with Date once JGit's PersonIdent class supports
+  // Instants
+  @SuppressWarnings("JdkObsolete")
   public Account insert(Account.Builder account) throws IOException {
     File path = getPath();
     try (Repository repo = new FileRepository(path);
         ObjectInserter oi = repo.newObjectInserter()) {
       PersonIdent ident =
-          new PersonIdent(new GerritPersonIdentProvider(flags.cfg).get(), account.registeredOn());
+          new PersonIdent(
+              new GerritPersonIdentProvider(flags.cfg).get(), Date.from(account.registeredOn()));
 
       Config accountConfig = new Config();
       AccountProperties.writeToAccountConfig(
@@ -110,7 +115,7 @@
       if (result != Result.NEW) {
         throw new IOException(String.format("Failed to update ref %s: %s", refName, result.name()));
       }
-      account.setMetaId(id.name()).build();
+      account.setMetaId(id.name());
     }
     return account.build();
   }
diff --git a/java/com/google/gerrit/pgm/init/BaseInit.java b/java/com/google/gerrit/pgm/init/BaseInit.java
index c1f5753..4592cbb 100644
--- a/java/com/google/gerrit/pgm/init/BaseInit.java
+++ b/java/com/google/gerrit/pgm/init/BaseInit.java
@@ -124,7 +124,7 @@
         } catch (StorageException e) {
           String msg = "Couldn't upgrade schema. Expected if slave and read-only database";
           System.err.println(msg);
-          logger.atSevere().withCause(e).log(msg);
+          logger.atSevere().withCause(e).log("%s", msg);
         }
 
         init.initializer.postRun(sysInjector);
diff --git a/java/com/google/gerrit/pgm/init/ExternalIdsOnInit.java b/java/com/google/gerrit/pgm/init/ExternalIdsOnInit.java
index 9b4d5bb..35892f2 100644
--- a/java/com/google/gerrit/pgm/init/ExternalIdsOnInit.java
+++ b/java/com/google/gerrit/pgm/init/ExternalIdsOnInit.java
@@ -64,7 +64,7 @@
     if (path != null) {
       try (Repository allUsersRepo = new FileRepository(path)) {
         ExternalIdNotes extIdNotes =
-            ExternalIdNotes.loadNoCacheUpdate(
+            ExternalIdNotes.load(
                 allUsers,
                 allUsersRepo,
                 externalIdFactory,
diff --git a/java/com/google/gerrit/pgm/init/GroupsOnInit.java b/java/com/google/gerrit/pgm/init/GroupsOnInit.java
index 2f12abb..020705e 100644
--- a/java/com/google/gerrit/pgm/init/GroupsOnInit.java
+++ b/java/com/google/gerrit/pgm/init/GroupsOnInit.java
@@ -41,6 +41,7 @@
 import java.io.IOException;
 import java.nio.file.Path;
 import java.sql.Timestamp;
+import java.time.Instant;
 import java.util.stream.Stream;
 import org.eclipse.jgit.errors.ConfigInvalidException;
 import org.eclipse.jgit.internal.storage.file.FileRepository;
@@ -165,10 +166,14 @@
     return AuditLogFormatter.createBackedBy(ImmutableSet.of(account), ImmutableSet.of(), serverId);
   }
 
-  private void commit(Repository repository, GroupConfig groupConfig, Timestamp groupCreatedOn)
+  // TODO(issue-15517): Fix the JdkObsolete issue with Date once JGit's PersonIdent class supports
+  // Instants
+  @SuppressWarnings("JdkObsolete")
+  private void commit(Repository repository, GroupConfig groupConfig, Instant groupCreatedOn)
       throws IOException {
     PersonIdent personIdent =
-        new PersonIdent(new GerritPersonIdentProvider(flags.cfg).get(), groupCreatedOn);
+        new PersonIdent(
+            new GerritPersonIdentProvider(flags.cfg).get(), Timestamp.from(groupCreatedOn));
     try (MetaDataUpdate metaDataUpdate = createMetaDataUpdate(repository, personIdent)) {
       groupConfig.commit(metaDataUpdate);
     }
diff --git a/java/com/google/gerrit/pgm/init/InitAdminUser.java b/java/com/google/gerrit/pgm/init/InitAdminUser.java
index d6a0133..4e854b5 100644
--- a/java/com/google/gerrit/pgm/init/InitAdminUser.java
+++ b/java/com/google/gerrit/pgm/init/InitAdminUser.java
@@ -120,7 +120,7 @@
 
         Account persistedAccount =
             accounts.insert(
-                Account.builder(id, TimeUtil.nowTs()).setFullName(name).setPreferredEmail(email));
+                Account.builder(id, TimeUtil.now()).setFullName(name).setPreferredEmail(email));
         // Only two groups should exist at this point in time and hence iterating over all of them
         // is cheap.
         Optional<GroupReference> adminGroupReference =
diff --git a/java/com/google/gerrit/pgm/init/api/GitRepositoryManagerOnInit.java b/java/com/google/gerrit/pgm/init/api/GitRepositoryManagerOnInit.java
index 8e69eb9..fabad49 100644
--- a/java/com/google/gerrit/pgm/init/api/GitRepositoryManagerOnInit.java
+++ b/java/com/google/gerrit/pgm/init/api/GitRepositoryManagerOnInit.java
@@ -23,7 +23,7 @@
 import java.io.File;
 import java.io.IOException;
 import java.nio.file.Path;
-import java.util.SortedSet;
+import java.util.NavigableSet;
 import org.eclipse.jgit.errors.RepositoryNotFoundException;
 import org.eclipse.jgit.internal.storage.file.FileRepository;
 import org.eclipse.jgit.lib.Repository;
@@ -65,7 +65,7 @@
   }
 
   @Override
-  public SortedSet<Project.NameKey> list() {
+  public NavigableSet<Project.NameKey> list() {
     throw new UnsupportedOperationException("not implemented");
   }
 
diff --git a/java/com/google/gerrit/pgm/util/BatchGitModule.java b/java/com/google/gerrit/pgm/util/BatchGitModule.java
index d39c2fd..fa585d3 100644
--- a/java/com/google/gerrit/pgm/util/BatchGitModule.java
+++ b/java/com/google/gerrit/pgm/util/BatchGitModule.java
@@ -15,6 +15,7 @@
 package com.google.gerrit.pgm.util;
 
 import com.google.gerrit.extensions.config.FactoryModule;
+import com.google.gerrit.extensions.events.GitBatchRefUpdateListener;
 import com.google.gerrit.extensions.events.GitReferenceUpdatedListener;
 import com.google.gerrit.extensions.registration.DynamicSet;
 import com.google.gerrit.server.git.GitModule;
@@ -24,6 +25,7 @@
 public class BatchGitModule extends FactoryModule {
   @Override
   protected void configure() {
+    DynamicSet.setOf(binder(), GitBatchRefUpdateListener.class);
     DynamicSet.setOf(binder(), GitReferenceUpdatedListener.class);
     DynamicSet.setOf(binder(), CommitValidationListener.class);
     install(new GitModule());
diff --git a/java/com/google/gerrit/pgm/util/BatchProgramModule.java b/java/com/google/gerrit/pgm/util/BatchProgramModule.java
index c397539..208ed1f 100644
--- a/java/com/google/gerrit/pgm/util/BatchProgramModule.java
+++ b/java/com/google/gerrit/pgm/util/BatchProgramModule.java
@@ -20,6 +20,7 @@
 import com.google.common.collect.ImmutableSet;
 import com.google.gerrit.entities.AccountGroup;
 import com.google.gerrit.entities.GroupReference;
+import com.google.gerrit.entities.SubmitRequirement;
 import com.google.gerrit.extensions.api.projects.CommentLinkInfo;
 import com.google.gerrit.extensions.common.AccountVisibility;
 import com.google.gerrit.extensions.config.FactoryModule;
@@ -41,7 +42,6 @@
 import com.google.gerrit.server.account.Realm;
 import com.google.gerrit.server.account.ServiceUserClassifierImpl;
 import com.google.gerrit.server.account.externalids.ExternalIdCacheModule;
-import com.google.gerrit.server.approval.ApprovalCacheImpl;
 import com.google.gerrit.server.cache.CacheRemovalListener;
 import com.google.gerrit.server.cache.h2.H2CacheModule;
 import com.google.gerrit.server.cache.mem.DefaultMemoryCacheModule;
@@ -83,11 +83,13 @@
 import com.google.gerrit.server.project.ProjectState;
 import com.google.gerrit.server.project.SubmitRequirementsEvaluatorImpl;
 import com.google.gerrit.server.project.SubmitRuleEvaluator;
+import com.google.gerrit.server.query.FileEditsPredicate;
 import com.google.gerrit.server.query.approval.ApprovalModule;
 import com.google.gerrit.server.query.change.ChangeData;
 import com.google.gerrit.server.query.change.ChangeIsVisibleToPredicate;
 import com.google.gerrit.server.query.change.ChangeQueryBuilder;
 import com.google.gerrit.server.query.change.ConflictsCacheImpl;
+import com.google.gerrit.server.query.change.DistinctVotersPredicate;
 import com.google.gerrit.server.restapi.group.GroupModule;
 import com.google.gerrit.server.rules.DefaultSubmitRule.DefaultSubmitRuleModule;
 import com.google.gerrit.server.rules.IgnoreSelfApprovalRule.IgnoreSelfApprovalRuleModule;
@@ -180,7 +182,6 @@
     modules.add(new GroupModule());
     modules.add(new NoteDbModule());
     modules.add(AccountCacheImpl.module());
-    modules.add(ApprovalCacheImpl.module());
     modules.add(ConflictsCacheImpl.module());
     modules.add(DefaultPreferencesCacheImpl.module());
     modules.add(GroupCacheImpl.module());
@@ -197,6 +198,7 @@
     factory(CapabilityCollection.Factory.class);
     factory(ChangeData.AssistedFactory.class);
     factory(ChangeIsVisibleToPredicate.Factory.class);
+    factory(DistinctVotersPredicate.Factory.class);
     factory(ProjectState.Factory.class);
 
     DynamicMap.mapOf(binder(), ChangeQueryBuilder.ChangeOperatorFactory.class);
@@ -210,6 +212,11 @@
     modules.add(new DefaultSubmitRuleModule());
     modules.add(new IgnoreSelfApprovalRuleModule());
 
+    // Global submit requirements
+    DynamicSet.setOf(binder(), SubmitRequirement.class);
+
+    factory(FileEditsPredicate.Factory.class);
+
     bind(ChangeJson.Factory.class).toProvider(Providers.of(null));
     bind(EventUtil.class).toProvider(Providers.of(null));
     bind(GitReferenceUpdated.class).toInstance(GitReferenceUpdated.DISABLED);
diff --git a/java/com/google/gerrit/pgm/util/ProxyUtil.java b/java/com/google/gerrit/pgm/util/ProxyUtil.java
index 3eb8187..c2c1141 100644
--- a/java/com/google/gerrit/pgm/util/ProxyUtil.java
+++ b/java/com/google/gerrit/pgm/util/ProxyUtil.java
@@ -59,7 +59,7 @@
       return;
     }
 
-    final URL u = new URL((!s.contains("://")) ? "http://" + s : s);
+    final URL u = new URL(!s.contains("://") ? "http://" + s : s);
     if (!"http".equals(u.getProtocol())) {
       throw new MalformedURLException("Invalid http_proxy: " + s + ": Only http supported.");
     }
diff --git a/java/com/google/gerrit/server/AssigneeStatusUpdate.java b/java/com/google/gerrit/server/AssigneeStatusUpdate.java
index 3d6242b..812aad1 100644
--- a/java/com/google/gerrit/server/AssigneeStatusUpdate.java
+++ b/java/com/google/gerrit/server/AssigneeStatusUpdate.java
@@ -16,18 +16,18 @@
 
 import com.google.auto.value.AutoValue;
 import com.google.gerrit.entities.Account;
-import java.sql.Timestamp;
+import java.time.Instant;
 import java.util.Optional;
 
 /** Change to an assignee's status. */
 @AutoValue
 public abstract class AssigneeStatusUpdate {
   public static AssigneeStatusUpdate create(
-      Timestamp ts, Account.Id updatedBy, Optional<Account.Id> currentAssignee) {
+      Instant ts, Account.Id updatedBy, Optional<Account.Id> currentAssignee) {
     return new AutoValue_AssigneeStatusUpdate(ts, updatedBy, currentAssignee);
   }
 
-  public abstract Timestamp date();
+  public abstract Instant date();
 
   public abstract Account.Id updatedBy();
 
diff --git a/java/com/google/gerrit/server/AuditEvent.java b/java/com/google/gerrit/server/AuditEvent.java
index 773a307..54bbe23 100644
--- a/java/com/google/gerrit/server/AuditEvent.java
+++ b/java/com/google/gerrit/server/AuditEvent.java
@@ -82,6 +82,12 @@
     return uuid.hashCode();
   }
 
+  // This is a value class that allows adding attributes by subclassing.
+  // Doing this is discouraged and using composition rather than inheritance to add fields to value
+  // types is preferred. However this class is part of the plugin API (used in the AuditListener
+  // extension point), hence we cannot change it without breaking plugins. Hence suppress the
+  // EqualsGetClass warning here.
+  @SuppressWarnings("EqualsGetClass")
   @Override
   public boolean equals(Object obj) {
     if (this == obj) {
diff --git a/java/com/google/gerrit/server/BUILD b/java/com/google/gerrit/server/BUILD
index 7080417..7a6187d 100644
--- a/java/com/google/gerrit/server/BUILD
+++ b/java/com/google/gerrit/server/BUILD
@@ -111,9 +111,9 @@
         "//lib/commons:codec",
         "//lib/commons:compress",
         "//lib/commons:dbcp",
-        "//lib/commons:lang",
         "//lib/commons:lang3",
         "//lib/commons:net",
+        "//lib/commons:text",
         "//lib/commons:validator",
         "//lib/errorprone:annotations",
         "//lib/flogger:api",
@@ -144,6 +144,7 @@
     visibility = ["//visibility:public"],
     deps = [
         ":server",
+        "//java/com/google/gerrit/entities",
         "//java/com/google/gerrit/extensions:api",
         "//java/com/google/gerrit/server/git/receive",
         "//java/com/google/gerrit/server/logging",
diff --git a/java/com/google/gerrit/server/ChangeMessagesUtil.java b/java/com/google/gerrit/server/ChangeMessagesUtil.java
index 8366b09..81cff6e 100644
--- a/java/com/google/gerrit/server/ChangeMessagesUtil.java
+++ b/java/com/google/gerrit/server/ChangeMessagesUtil.java
@@ -145,7 +145,7 @@
     ChangeMessageInfo cmi = new ChangeMessageInfo();
     cmi.id = message.getKey().uuid();
     cmi.author = accountLoader.get(message.getAuthor());
-    cmi.date = message.getWrittenOn();
+    cmi.setDate(message.getWrittenOn());
     cmi.message = message.getMessage();
     cmi.tag = message.getTag();
     cmi._revisionNumber = patchNum != null ? patchNum.get() : null;
diff --git a/java/com/google/gerrit/server/CmdLineParserModule.java b/java/com/google/gerrit/server/CmdLineParserModule.java
index d943889..be6b4cd8 100644
--- a/java/com/google/gerrit/server/CmdLineParserModule.java
+++ b/java/com/google/gerrit/server/CmdLineParserModule.java
@@ -23,17 +23,17 @@
 import com.google.gerrit.server.args4j.AccountGroupUUIDHandler;
 import com.google.gerrit.server.args4j.AccountIdHandler;
 import com.google.gerrit.server.args4j.ChangeIdHandler;
+import com.google.gerrit.server.args4j.InstantHandler;
 import com.google.gerrit.server.args4j.ObjectIdHandler;
 import com.google.gerrit.server.args4j.PatchSetIdHandler;
 import com.google.gerrit.server.args4j.ProjectHandler;
 import com.google.gerrit.server.args4j.SocketAddressHandler;
-import com.google.gerrit.server.args4j.TimestampHandler;
 import com.google.gerrit.server.project.ProjectState;
 import com.google.gerrit.util.cli.CmdLineParser;
 import com.google.gerrit.util.cli.OptionHandlerUtil;
 import com.google.gerrit.util.cli.OptionHandlers;
 import java.net.SocketAddress;
-import java.sql.Timestamp;
+import java.time.Instant;
 import org.eclipse.jgit.lib.ObjectId;
 import org.kohsuke.args4j.spi.OptionHandler;
 
@@ -49,11 +49,11 @@
     registerOptionHandler(AccountGroup.Id.class, AccountGroupIdHandler.class);
     registerOptionHandler(AccountGroup.UUID.class, AccountGroupUUIDHandler.class);
     registerOptionHandler(Change.Id.class, ChangeIdHandler.class);
+    registerOptionHandler(Instant.class, InstantHandler.class);
     registerOptionHandler(ObjectId.class, ObjectIdHandler.class);
     registerOptionHandler(PatchSet.Id.class, PatchSetIdHandler.class);
     registerOptionHandler(ProjectState.class, ProjectHandler.class);
     registerOptionHandler(SocketAddress.class, SocketAddressHandler.class);
-    registerOptionHandler(Timestamp.class, TimestampHandler.class);
   }
 
   private <T> void registerOptionHandler(Class<T> type, Class<? extends OptionHandler<T>> impl) {
diff --git a/java/com/google/gerrit/server/CommentsUtil.java b/java/com/google/gerrit/server/CommentsUtil.java
index ba9f6d6..8198ce4 100644
--- a/java/com/google/gerrit/server/CommentsUtil.java
+++ b/java/com/google/gerrit/server/CommentsUtil.java
@@ -44,17 +44,20 @@
 import com.google.gerrit.server.notedb.ChangeUpdate;
 import com.google.gerrit.server.patch.DiffNotAvailableException;
 import com.google.gerrit.server.patch.DiffOperations;
+import com.google.gerrit.server.patch.DiffOptions;
 import com.google.gerrit.server.patch.filediff.FileDiffOutput;
 import com.google.gerrit.server.update.ChangeContext;
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
 import java.io.IOException;
-import java.sql.Timestamp;
+import java.time.Instant;
 import java.util.ArrayList;
 import java.util.Collection;
+import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Optional;
+import java.util.Set;
 import org.eclipse.jgit.lib.ObjectId;
 import org.eclipse.jgit.lib.Ref;
 import org.eclipse.jgit.lib.Repository;
@@ -64,7 +67,7 @@
 @Singleton
 public class CommentsUtil {
   public static final Ordering<Comment> COMMENT_ORDER =
-      new Ordering<Comment>() {
+      new Ordering<>() {
         @Override
         public int compare(Comment c1, Comment c2) {
           return ComparisonChain.start()
@@ -78,7 +81,7 @@
       };
 
   public static final Ordering<CommentInfo> COMMENT_INFO_ORDER =
-      new Ordering<CommentInfo>() {
+      new Ordering<>() {
         @Override
         public int compare(CommentInfo a, CommentInfo b) {
           return ComparisonChain.start()
@@ -130,7 +133,7 @@
   public HumanComment newHumanComment(
       ChangeNotes changeNotes,
       CurrentUser currentUser,
-      Timestamp when,
+      Instant when,
       String path,
       PatchSet.Id psId,
       short side,
@@ -302,7 +305,7 @@
   }
 
   private static boolean isAfter(CommentInfo c, ChangeMessage cm) {
-    return c.updated.after(cm.getWrittenOn());
+    return c.getUpdated().isAfter(cm.getWrittenOn());
   }
 
   /**
@@ -335,7 +338,7 @@
   }
 
   public void putHumanComments(
-      ChangeUpdate update, HumanComment.Status status, Iterable<HumanComment> comments) {
+      ChangeUpdate update, Comment.Status status, Iterable<HumanComment> comments) {
     for (HumanComment c : comments) {
       update.putComment(status, c);
     }
@@ -438,7 +441,7 @@
       // unignore the test in PortedCommentsIT.
       Map<String, FileDiffOutput> modifiedFiles =
           diffOperations.listModifiedFilesAgainstParent(
-              change.getProject(), patchset.commitId(), /* parentNum= */ 0);
+              change.getProject(), patchset.commitId(), /* parentNum= */ 0, DiffOptions.DEFAULTS);
       return modifiedFiles.isEmpty()
           ? null
           : modifiedFiles.values().iterator().next().oldCommitId();
@@ -465,10 +468,35 @@
     }
   }
 
+  /** returns all changes that contain draft comments of {@code accountId}. */
+  public Collection<Change.Id> getChangesWithDrafts(Account.Id accountId) {
+    try (Repository repo = repoManager.openRepository(allUsers)) {
+      return getChangesWithDrafts(repo, accountId);
+    } catch (IOException e) {
+      throw new StorageException(e);
+    }
+  }
+
   private Collection<Ref> getDraftRefs(Repository repo, Change.Id changeId) throws IOException {
     return repo.getRefDatabase().getRefsByPrefix(RefNames.refsDraftCommentsPrefix(changeId));
   }
 
+  private Collection<Change.Id> getChangesWithDrafts(Repository repo, Account.Id accountId)
+      throws IOException {
+    Set<Change.Id> changes = new HashSet<>();
+    for (Ref ref : repo.getRefDatabase().getRefsByPrefix(RefNames.REFS_DRAFT_COMMENTS)) {
+      Integer accountIdFromRef = RefNames.parseRefSuffix(ref.getName());
+      if (accountIdFromRef != null && accountIdFromRef == accountId.get()) {
+        Change.Id changeId = Change.Id.fromAllUsersRef(ref.getName());
+        if (changeId == null) {
+          continue;
+        }
+        changes.add(changeId);
+      }
+    }
+    return changes;
+  }
+
   private static <T extends Comment> List<T> sort(List<T> comments) {
     comments.sort(COMMENT_ORDER);
     return comments;
diff --git a/java/com/google/gerrit/server/CommonConverters.java b/java/com/google/gerrit/server/CommonConverters.java
index 2b48169..e7fd1c5 100644
--- a/java/com/google/gerrit/server/CommonConverters.java
+++ b/java/com/google/gerrit/server/CommonConverters.java
@@ -15,7 +15,6 @@
 package com.google.gerrit.server;
 
 import com.google.gerrit.extensions.common.GitPerson;
-import java.sql.Timestamp;
 import org.eclipse.jgit.lib.PersonIdent;
 
 /**
@@ -26,11 +25,14 @@
  * static utility methods.
  */
 public class CommonConverters {
+  // TODO(issue-15517): Fix the JdkObsolete issue with Date once JGit's PersonIdent class supports
+  // Instants
+  @SuppressWarnings("JdkObsolete")
   public static GitPerson toGitPerson(PersonIdent ident) {
     GitPerson result = new GitPerson();
     result.name = ident.getName();
     result.email = ident.getEmailAddress();
-    result.date = new Timestamp(ident.getWhen().getTime());
+    result.setDate(ident.getWhen().toInstant());
     result.tz = ident.getTimeZoneOffset();
     return result;
   }
diff --git a/java/com/google/gerrit/server/ExceptionHookImpl.java b/java/com/google/gerrit/server/ExceptionHookImpl.java
index 3986842..781f196 100644
--- a/java/com/google/gerrit/server/ExceptionHookImpl.java
+++ b/java/com/google/gerrit/server/ExceptionHookImpl.java
@@ -18,7 +18,7 @@
 import com.google.common.base.Throwables;
 import com.google.common.collect.ImmutableList;
 import com.google.gerrit.common.Nullable;
-import com.google.gerrit.exceptions.InternalServerWithUserMessageException;
+import com.google.gerrit.exceptions.MergeUpdateException;
 import com.google.gerrit.git.LockFailureException;
 import com.google.gerrit.server.project.ProjectConfig;
 import java.util.Optional;
@@ -74,7 +74,7 @@
               + "\n"
               + CONTACT_PROJECT_OWNER_USER_MESSAGE);
     }
-    if (throwable instanceof InternalServerWithUserMessageException) {
+    if (throwable instanceof MergeUpdateException) {
       return ImmutableList.of(throwable.getMessage());
     }
     return ImmutableList.of();
diff --git a/java/com/google/gerrit/server/IdentifiedUser.java b/java/com/google/gerrit/server/IdentifiedUser.java
index eb3e324..122e18d 100644
--- a/java/com/google/gerrit/server/IdentifiedUser.java
+++ b/java/com/google/gerrit/server/IdentifiedUser.java
@@ -49,7 +49,7 @@
 import java.net.MalformedURLException;
 import java.net.SocketAddress;
 import java.net.URL;
-import java.util.Date;
+import java.time.Instant;
 import java.util.Optional;
 import java.util.Set;
 import java.util.TimeZone;
@@ -427,10 +427,10 @@
   }
 
   public PersonIdent newRefLogIdent() {
-    return newRefLogIdent(new Date(), TimeZone.getDefault());
+    return newRefLogIdent(Instant.now(), TimeZone.getDefault());
   }
 
-  public PersonIdent newRefLogIdent(Date when, TimeZone tz) {
+  public PersonIdent newRefLogIdent(Instant when, TimeZone tz) {
     final Account ua = getAccount();
 
     String name = ua.fullName();
@@ -450,14 +450,22 @@
               ? constructMailAddress(ua, "unknown")
               : ua.preferredEmail();
     }
-    return new PersonIdent(name, user, when, tz);
+
+    return newPersonIdent(name, user, when, tz);
   }
 
   private String constructMailAddress(Account ua, String host) {
     return getUserName().orElse("") + "|account-" + ua.id().toString() + "@" + host;
   }
 
-  public PersonIdent newCommitterIdent(Date when, TimeZone tz) {
+  // TODO(issue-15517): Fix the JdkObsolete issue with Date once JGit's PersonIdent class supports
+  // Instants
+  @SuppressWarnings("JdkObsolete")
+  public PersonIdent newCommitterIdent(PersonIdent ident) {
+    return newCommitterIdent(ident.getWhen().toInstant(), ident.getTimeZone());
+  }
+
+  public PersonIdent newCommitterIdent(Instant when, TimeZone tz) {
     final Account ua = getAccount();
     String name = ua.fullName();
     String email = ua.preferredEmail();
@@ -492,7 +500,7 @@
       }
     }
 
-    return new PersonIdent(name, email, when, tz);
+    return newPersonIdent(name, email, when, tz);
   }
 
   @Override
@@ -560,4 +568,19 @@
     }
     return host;
   }
+
+  /**
+   * Create a {@link PersonIdent} from an {@code Instant} and a {@link TimeZone}.
+   *
+   * <p>We use the {@link PersonIdent#PersonIdent(String, String, long, int)} constructor to avoid
+   * doing a conversion to {@code java.util.Date} here. For the {@code int aTZ} argument, which is
+   * the time zone, we do the same computation as in {@link PersonIdent#PersonIdent(String, String,
+   * java.util.Date, TimeZone)} (just instead of getting the epoch millis from {@code
+   * java.util.Date} we get them from {@link Instant}).
+   */
+  // TODO(issue-15517): Drop this method once JGit's PersonIdent class supports Instants
+  private static PersonIdent newPersonIdent(String name, String email, Instant when, TimeZone tz) {
+    return new PersonIdent(
+        name, email, when.toEpochMilli(), tz.getOffset(when.toEpochMilli()) / (60 * 1000));
+  }
 }
diff --git a/java/com/google/gerrit/server/LibModuleLoader.java b/java/com/google/gerrit/server/LibModuleLoader.java
index f7e04b4..5c0f8e4 100644
--- a/java/com/google/gerrit/server/LibModuleLoader.java
+++ b/java/com/google/gerrit/server/LibModuleLoader.java
@@ -87,9 +87,7 @@
     try {
       return (Class<Module>) Class.forName(className);
     } catch (ClassNotFoundException | LinkageError e) {
-      String msg = "Cannot load LibModule " + className;
-      logger.atSevere().withCause(e).log(msg);
-      throw new ProvisionException(msg, e);
+      throw new ProvisionException("Cannot load LibModule " + className, e);
     }
   }
 }
diff --git a/java/com/google/gerrit/server/PatchSetUtil.java b/java/com/google/gerrit/server/PatchSetUtil.java
index 326ddf4..3d449b7 100644
--- a/java/com/google/gerrit/server/PatchSetUtil.java
+++ b/java/com/google/gerrit/server/PatchSetUtil.java
@@ -39,7 +39,6 @@
 import com.google.inject.Provider;
 import com.google.inject.Singleton;
 import java.io.IOException;
-import java.sql.Timestamp;
 import java.util.List;
 import java.util.Optional;
 import java.util.Set;
@@ -106,7 +105,7 @@
         .id(psId)
         .commitId(commit)
         .uploader(update.getAccountId())
-        .createdOn(new Timestamp(update.getWhen().getTime()))
+        .createdOn(update.getWhen())
         .groups(groups)
         .pushCertificate(Optional.ofNullable(pushCertificate))
         .description(Optional.ofNullable(description))
diff --git a/java/com/google/gerrit/server/PublishCommentUtil.java b/java/com/google/gerrit/server/PublishCommentUtil.java
index 4d19dd0..de5f023 100644
--- a/java/com/google/gerrit/server/PublishCommentUtil.java
+++ b/java/com/google/gerrit/server/PublishCommentUtil.java
@@ -32,6 +32,7 @@
 import com.google.gerrit.server.update.ChangeContext;
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
+import java.sql.Timestamp;
 import java.util.Collection;
 import java.util.HashSet;
 import java.util.Map;
@@ -90,7 +91,7 @@
             draftComment, psIdOfDraftComment, notes.getProjectName());
         continue;
       }
-      draftComment.writtenOn = ctx.getWhen();
+      draftComment.writtenOn = Timestamp.from(ctx.getWhen());
       draftComment.tag = tag;
       // Draft may have been created by a different real user; copy the current real user. (Only
       // applies to X-Gerrit-RunAs, since modifying drafts via on_behalf_of is not allowed.)
diff --git a/java/com/google/gerrit/server/RequestCleanup.java b/java/com/google/gerrit/server/RequestCleanup.java
index e07d148..1d421ed 100644
--- a/java/com/google/gerrit/server/RequestCleanup.java
+++ b/java/com/google/gerrit/server/RequestCleanup.java
@@ -16,8 +16,8 @@
 
 import com.google.common.flogger.FluentLogger;
 import com.google.inject.servlet.RequestScoped;
+import java.util.ArrayList;
 import java.util.Iterator;
-import java.util.LinkedList;
 import java.util.List;
 
 /** Registers cleanup activities to be completed when a scope ends. */
@@ -25,7 +25,7 @@
 public class RequestCleanup implements Runnable {
   private static final FluentLogger logger = FluentLogger.forEnclosingClass();
 
-  private final List<Runnable> cleanup = new LinkedList<>();
+  private final List<Runnable> cleanup = new ArrayList<>();
   private boolean ran;
 
   /** Register a task to be completed after the request ends. */
diff --git a/java/com/google/gerrit/server/ReviewerByEmailSet.java b/java/com/google/gerrit/server/ReviewerByEmailSet.java
index 4a317c3..c6ba7b5 100644
--- a/java/com/google/gerrit/server/ReviewerByEmailSet.java
+++ b/java/com/google/gerrit/server/ReviewerByEmailSet.java
@@ -19,7 +19,7 @@
 import com.google.common.collect.Table;
 import com.google.gerrit.entities.Address;
 import com.google.gerrit.server.notedb.ReviewerStateInternal;
-import java.sql.Timestamp;
+import java.time.Instant;
 
 /**
  * Set of reviewers on a change that do not have a Gerrit account and were added by email instead.
@@ -30,8 +30,7 @@
 public class ReviewerByEmailSet {
   private static final ReviewerByEmailSet EMPTY = new ReviewerByEmailSet(ImmutableTable.of());
 
-  public static ReviewerByEmailSet fromTable(
-      Table<ReviewerStateInternal, Address, Timestamp> table) {
+  public static ReviewerByEmailSet fromTable(Table<ReviewerStateInternal, Address, Instant> table) {
     return new ReviewerByEmailSet(table);
   }
 
@@ -39,10 +38,10 @@
     return EMPTY;
   }
 
-  private final ImmutableTable<ReviewerStateInternal, Address, Timestamp> table;
+  private final ImmutableTable<ReviewerStateInternal, Address, Instant> table;
   private ImmutableSet<Address> users;
 
-  private ReviewerByEmailSet(Table<ReviewerStateInternal, Address, Timestamp> table) {
+  private ReviewerByEmailSet(Table<ReviewerStateInternal, Address, Instant> table) {
     this.table = ImmutableTable.copyOf(table);
   }
 
@@ -58,7 +57,7 @@
     return table.row(state).keySet();
   }
 
-  public ImmutableTable<ReviewerStateInternal, Address, Timestamp> asTable() {
+  public ImmutableTable<ReviewerStateInternal, Address, Instant> asTable() {
     return table;
   }
 
diff --git a/java/com/google/gerrit/server/ReviewerSet.java b/java/com/google/gerrit/server/ReviewerSet.java
index 0f6bf29..0ff68e0 100644
--- a/java/com/google/gerrit/server/ReviewerSet.java
+++ b/java/com/google/gerrit/server/ReviewerSet.java
@@ -25,7 +25,7 @@
 import com.google.gerrit.entities.Account;
 import com.google.gerrit.entities.PatchSetApproval;
 import com.google.gerrit.server.notedb.ReviewerStateInternal;
-import java.sql.Timestamp;
+import java.time.Instant;
 
 /**
  * Set of reviewers on a change.
@@ -38,7 +38,7 @@
 
   public static ReviewerSet fromApprovals(Iterable<PatchSetApproval> approvals) {
     PatchSetApproval first = null;
-    Table<ReviewerStateInternal, Account.Id, Timestamp> reviewers = HashBasedTable.create();
+    Table<ReviewerStateInternal, Account.Id, Instant> reviewers = HashBasedTable.create();
     for (PatchSetApproval psa : approvals) {
       if (first == null) {
         first = psa;
@@ -58,7 +58,7 @@
     return new ReviewerSet(reviewers);
   }
 
-  public static ReviewerSet fromTable(Table<ReviewerStateInternal, Account.Id, Timestamp> table) {
+  public static ReviewerSet fromTable(Table<ReviewerStateInternal, Account.Id, Instant> table) {
     return new ReviewerSet(table);
   }
 
@@ -66,10 +66,10 @@
     return EMPTY;
   }
 
-  private final ImmutableTable<ReviewerStateInternal, Account.Id, Timestamp> table;
+  private final ImmutableTable<ReviewerStateInternal, Account.Id, Instant> table;
   private ImmutableSet<Account.Id> accounts;
 
-  private ReviewerSet(Table<ReviewerStateInternal, Account.Id, Timestamp> table) {
+  private ReviewerSet(Table<ReviewerStateInternal, Account.Id, Instant> table) {
     this.table = ImmutableTable.copyOf(table);
   }
 
@@ -85,7 +85,7 @@
     return table.row(state).keySet();
   }
 
-  public ImmutableTable<ReviewerStateInternal, Account.Id, Timestamp> asTable() {
+  public ImmutableTable<ReviewerStateInternal, Account.Id, Instant> asTable() {
     return table;
   }
 
diff --git a/java/com/google/gerrit/server/ReviewerStatusUpdate.java b/java/com/google/gerrit/server/ReviewerStatusUpdate.java
index 938d985..1e0aa43 100644
--- a/java/com/google/gerrit/server/ReviewerStatusUpdate.java
+++ b/java/com/google/gerrit/server/ReviewerStatusUpdate.java
@@ -17,17 +17,17 @@
 import com.google.auto.value.AutoValue;
 import com.google.gerrit.entities.Account;
 import com.google.gerrit.server.notedb.ReviewerStateInternal;
-import java.sql.Timestamp;
+import java.time.Instant;
 
 /** Change to a reviewer's status. */
 @AutoValue
 public abstract class ReviewerStatusUpdate {
   public static ReviewerStatusUpdate create(
-      Timestamp ts, Account.Id updatedBy, Account.Id reviewer, ReviewerStateInternal state) {
+      Instant ts, Account.Id updatedBy, Account.Id reviewer, ReviewerStateInternal state) {
     return new AutoValue_ReviewerStatusUpdate(ts, updatedBy, reviewer, state);
   }
 
-  public abstract Timestamp date();
+  public abstract Instant date();
 
   public abstract Account.Id updatedBy();
 
diff --git a/java/com/google/gerrit/server/StarredChangesUtil.java b/java/com/google/gerrit/server/StarredChangesUtil.java
index f7193b7..95d891e 100644
--- a/java/com/google/gerrit/server/StarredChangesUtil.java
+++ b/java/com/google/gerrit/server/StarredChangesUtil.java
@@ -54,10 +54,10 @@
 import com.google.inject.Singleton;
 import java.io.IOException;
 import java.util.Collection;
-import java.util.HashSet;
+import java.util.Collections;
 import java.util.List;
+import java.util.NavigableSet;
 import java.util.Set;
-import java.util.SortedSet;
 import java.util.TreeSet;
 import org.eclipse.jgit.lib.BatchRefUpdate;
 import org.eclipse.jgit.lib.Constants;
@@ -113,7 +113,7 @@
   @AutoValue
   public abstract static class StarRef {
     private static final StarRef MISSING =
-        new AutoValue_StarredChangesUtil_StarRef(null, ImmutableSortedSet.of());
+        new AutoValue_StarredChangesUtil_StarRef(null, Collections.emptyNavigableSet());
 
     private static StarRef create(Ref ref, Iterable<String> labels) {
       return new AutoValue_StarredChangesUtil_StarRef(
@@ -123,7 +123,7 @@
     @Nullable
     public abstract Ref ref();
 
-    public abstract ImmutableSortedSet<String> labels();
+    public abstract NavigableSet<String> labels();
 
     public ObjectId objectId() {
       return ref() != null ? ref().getObjectId() : ObjectId.zeroId();
@@ -185,7 +185,7 @@
     this.queryProvider = queryProvider;
   }
 
-  public ImmutableSortedSet<String> getLabels(Account.Id accountId, Change.Id changeId) {
+  public NavigableSet<String> getLabels(Account.Id accountId, Change.Id changeId) {
     try (Repository repo = repoManager.openRepository(allUsers)) {
       return readLabels(repo, RefNames.refsStarredChanges(changeId, accountId)).labels();
     } catch (IOException e) {
@@ -197,7 +197,7 @@
     }
   }
 
-  public ImmutableSortedSet<String> star(
+  public NavigableSet<String> star(
       Account.Id accountId,
       Project.NameKey project,
       Change.Id changeId,
@@ -208,7 +208,7 @@
       String refName = RefNames.refsStarredChanges(changeId, accountId);
       StarRef old = readLabels(repo, refName);
 
-      Set<String> labels = new HashSet<>(old.labels());
+      NavigableSet<String> labels = new TreeSet<>(old.labels());
       if (labelsToAdd != null) {
         labels.addAll(labelsToAdd);
       }
@@ -224,7 +224,7 @@
       }
 
       indexer.index(project, changeId);
-      return ImmutableSortedSet.copyOf(labels);
+      return Collections.unmodifiableNavigableSet(labels);
     } catch (IOException e) {
       throw new StorageException(
           String.format("Star change %d for account %d failed", changeId.get(), accountId.get()),
@@ -289,6 +289,35 @@
     }
   }
 
+  public ImmutableSet<Change.Id> byAccountId(Account.Id accountId, String label) {
+    try (Repository repo = repoManager.openRepository(allUsers)) {
+      ImmutableSet.Builder<Change.Id> builder = ImmutableSet.builder();
+      for (Ref ref : repo.getRefDatabase().getRefsByPrefix(RefNames.REFS_STARRED_CHANGES)) {
+        Account.Id currentAccountId = Account.Id.fromRef(ref.getName());
+        // Skip all refs that don't correspond with accountId.
+        if (currentAccountId == null || !currentAccountId.equals(accountId)) {
+          continue;
+        }
+        // Skip all refs that don't contain the required label.
+        StarRef starRef = readLabels(repo, ref.getName());
+        if (!starRef.labels().contains(label)) {
+          continue;
+        }
+
+        // Skip invalid change ids.
+        Change.Id changeId = Change.Id.fromAllUsersRef(ref.getName());
+        if (changeId == null) {
+          continue;
+        }
+        builder.add(changeId);
+      }
+      return builder.build();
+    } catch (IOException e) {
+      throw new StorageException(
+          String.format("Get starred changes for account %d failed", accountId.get()), e);
+    }
+  }
+
   public ImmutableListMultimap<Account.Id, String> byChangeFromIndex(Change.Id changeId) {
     List<ChangeData> changeData =
         queryProvider
@@ -397,7 +426,7 @@
       return;
     }
 
-    SortedSet<String> invalidLabels = new TreeSet<>();
+    NavigableSet<String> invalidLabels = new TreeSet<>();
     for (String label : labels) {
       if (CharMatcher.whitespace().matchesAnyOf(label)) {
         invalidLabels.add(label);
diff --git a/java/com/google/gerrit/server/WebLinks.java b/java/com/google/gerrit/server/WebLinks.java
index 2cf2326..58396f5 100644
--- a/java/com/google/gerrit/server/WebLinks.java
+++ b/java/com/google/gerrit/server/WebLinks.java
@@ -39,23 +39,11 @@
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
 import java.util.function.Function;
-import java.util.function.Predicate;
 
 @Singleton
 public class WebLinks {
   private static final FluentLogger logger = FluentLogger.forEnclosingClass();
 
-  private static final Predicate<WebLinkInfo> INVALID_WEBLINK =
-      link -> {
-        if (link == null) {
-          return false;
-        } else if (Strings.isNullOrEmpty(link.name) || Strings.isNullOrEmpty(link.url)) {
-          logger.atWarning().log("%s is missing name and/or url", link.getClass().getName());
-          return false;
-        }
-        return true;
-      };
-
   private final DynamicSet<PatchSetWebLink> patchSetLinks;
   private final DynamicSet<ResolveConflictsWebLink> resolveConflictsLinks;
   private final DynamicSet<ParentWebLink> parentLinks;
@@ -98,12 +86,19 @@
    * @param commit SHA1 of commit.
    * @param commitMessage the commit message of the commit.
    * @param branchName branch of the commit.
+   * @param changeKey change Identifier for this change
    */
   public ImmutableList<WebLinkInfo> getPatchSetLinks(
-      Project.NameKey project, String commit, String commitMessage, String branchName) {
+      Project.NameKey project,
+      String commit,
+      String commitMessage,
+      String branchName,
+      String changeKey) {
     return filterLinks(
         patchSetLinks,
-        webLink -> webLink.getPatchSetWebLink(project.get(), commit, commitMessage, branchName));
+        webLink ->
+            webLink.getPatchSetWebLink(
+                project.get(), commit, commitMessage, branchName, changeKey));
   }
 
   /**
@@ -179,7 +174,7 @@
     }
     return Streams.stream(fileHistoryLinks)
         .map(webLink -> webLink.getFileHistoryWebLink(project, revision, file))
-        .filter(INVALID_WEBLINK)
+        .filter(WebLinks::isValid)
         .collect(toImmutableList());
   }
 
@@ -218,7 +213,7 @@
                     patchSetIdB,
                     revisionB,
                     fileB))
-        .filter(INVALID_WEBLINK)
+        .filter(WebLinks::isValid)
         .collect(toImmutableList());
   }
 
@@ -255,7 +250,17 @@
       DynamicSet<T> links, Function<T, WebLinkInfo> transformer) {
     return Streams.stream(links)
         .map(transformer)
-        .filter(INVALID_WEBLINK)
+        .filter(WebLinks::isValid)
         .collect(toImmutableList());
   }
+
+  private static boolean isValid(WebLinkInfo link) {
+    if (link == null) {
+      return false;
+    } else if (Strings.isNullOrEmpty(link.name) || Strings.isNullOrEmpty(link.url)) {
+      logger.atWarning().log("%s is missing name and/or url", link.getClass().getName());
+      return false;
+    }
+    return true;
+  }
 }
diff --git a/java/com/google/gerrit/server/account/AccountCacheImpl.java b/java/com/google/gerrit/server/account/AccountCacheImpl.java
index 093af68..1d9150d 100644
--- a/java/com/google/gerrit/server/account/AccountCacheImpl.java
+++ b/java/com/google/gerrit/server/account/AccountCacheImpl.java
@@ -153,7 +153,7 @@
   }
 
   private AccountState missing(Account.Id accountId) {
-    Account.Builder account = Account.builder(accountId, TimeUtil.nowTs());
+    Account.Builder account = Account.builder(accountId, TimeUtil.now());
     account.setActive(false);
     return AccountState.forAccount(account.build());
   }
diff --git a/java/com/google/gerrit/server/account/AccountConfig.java b/java/com/google/gerrit/server/account/AccountConfig.java
index 45f1f35..28e881e1 100644
--- a/java/com/google/gerrit/server/account/AccountConfig.java
+++ b/java/com/google/gerrit/server/account/AccountConfig.java
@@ -34,8 +34,9 @@
 import com.google.gerrit.server.git.meta.VersionedMetaData;
 import com.google.gerrit.server.util.time.TimeUtil;
 import java.io.IOException;
-import java.sql.Timestamp;
+import java.time.Instant;
 import java.util.ArrayList;
+import java.util.Date;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
@@ -177,7 +178,7 @@
    * @throws DuplicateKeyException if the user branch already exists
    */
   public Account getNewAccount() throws DuplicateKeyException {
-    return getNewAccount(TimeUtil.nowTs());
+    return getNewAccount(TimeUtil.now());
   }
 
   /**
@@ -186,7 +187,7 @@
    * @return the new account
    * @throws DuplicateKeyException if the user branch already exists
    */
-  Account getNewAccount(Timestamp registeredOn) throws DuplicateKeyException {
+  Account getNewAccount(Instant registeredOn) throws DuplicateKeyException {
     checkLoaded();
     if (revision != null) {
       throw new DuplicateKeyException(String.format("account %s already exists", accountId));
@@ -216,7 +217,7 @@
       rw.reset();
       rw.markStart(revision);
       rw.sort(RevSort.REVERSE);
-      Timestamp registeredOn = new Timestamp(rw.next().getCommitTime() * 1000L);
+      Instant registeredOn = Instant.ofEpochMilli(rw.next().getCommitTime() * 1000L);
 
       Config accountConfig = readConfig(AccountProperties.ACCOUNT_CONFIG);
       loadedAccountProperties =
@@ -257,6 +258,9 @@
     return c;
   }
 
+  // TODO(issue-15517): Fix the JdkObsolete issue with Date once JGit's PersonIdent class supports
+  // Instants
+  @SuppressWarnings("JdkObsolete")
   @Override
   protected boolean onSave(CommitBuilder commit) throws IOException, ConfigInvalidException {
     checkLoaded();
@@ -274,9 +278,9 @@
         commit.setMessage("Create account\n");
       }
 
-      Timestamp registeredOn = loadedAccountProperties.get().getRegisteredOn();
-      commit.setAuthor(new PersonIdent(commit.getAuthor(), registeredOn));
-      commit.setCommitter(new PersonIdent(commit.getCommitter(), registeredOn));
+      Instant registeredOn = loadedAccountProperties.get().getRegisteredOn();
+      commit.setAuthor(new PersonIdent(commit.getAuthor(), Date.from(registeredOn)));
+      commit.setCommitter(new PersonIdent(commit.getCommitter(), Date.from(registeredOn)));
     }
 
     saveAccount();
diff --git a/java/com/google/gerrit/server/account/AccountControl.java b/java/com/google/gerrit/server/account/AccountControl.java
index 3f7f3f2..f5f9b3d 100644
--- a/java/com/google/gerrit/server/account/AccountControl.java
+++ b/java/com/google/gerrit/server/account/AccountControl.java
@@ -24,7 +24,6 @@
 import com.google.gerrit.entities.PermissionRule;
 import com.google.gerrit.exceptions.NoSuchGroupException;
 import com.google.gerrit.extensions.common.AccountVisibility;
-import com.google.gerrit.extensions.restapi.AuthException;
 import com.google.gerrit.server.CurrentUser;
 import com.google.gerrit.server.IdentifiedUser;
 import com.google.gerrit.server.group.SystemGroupBackend;
@@ -259,10 +258,7 @@
   private boolean viewAll() {
     if (viewAll == null) {
       try {
-        perm.check(GlobalPermission.VIEW_ALL_ACCOUNTS);
-        viewAll = true;
-      } catch (AuthException e) {
-        viewAll = false;
+        viewAll = perm.test(GlobalPermission.VIEW_ALL_ACCOUNTS);
       } catch (PermissionBackendException e) {
         logger.atFine().withCause(e).log(
             "Failed to check %s global capability for user %s",
diff --git a/java/com/google/gerrit/server/account/AccountManager.java b/java/com/google/gerrit/server/account/AccountManager.java
index 407d2f7..891a467 100644
--- a/java/com/google/gerrit/server/account/AccountManager.java
+++ b/java/com/google/gerrit/server/account/AccountManager.java
@@ -264,14 +264,16 @@
     }
 
     if (!accountUpdates.isEmpty()) {
-      accountsUpdateProvider
-          .get()
-          .update(
-              "Update Account on Login",
-              user.getAccountId(),
-              AccountsUpdate.joinConsumers(accountUpdates))
-          .orElseThrow(
-              () -> new StorageException("Account " + user.getAccountId() + " has been deleted"));
+      Optional<AccountState> updatedAccount =
+          accountsUpdateProvider
+              .get()
+              .update(
+                  "Update Account on Login",
+                  user.getAccountId(),
+                  AccountsUpdate.joinConsumers(accountUpdates));
+      if (!updatedAccount.isPresent()) {
+        throw new StorageException("Account " + user.getAccountId() + " has been deleted");
+      }
     }
   }
 
diff --git a/java/com/google/gerrit/server/account/AccountProperties.java b/java/com/google/gerrit/server/account/AccountProperties.java
index 9b7ca81..928d851 100644
--- a/java/com/google/gerrit/server/account/AccountProperties.java
+++ b/java/com/google/gerrit/server/account/AccountProperties.java
@@ -17,7 +17,7 @@
 import com.google.common.base.Strings;
 import com.google.gerrit.common.Nullable;
 import com.google.gerrit.entities.Account;
-import java.sql.Timestamp;
+import java.time.Instant;
 import org.eclipse.jgit.lib.Config;
 import org.eclipse.jgit.lib.ObjectId;
 
@@ -57,16 +57,13 @@
   public static final String KEY_STATUS = "status";
 
   private final Account.Id accountId;
-  private final Timestamp registeredOn;
+  private final Instant registeredOn;
   private final Config accountConfig;
   private @Nullable ObjectId metaId;
   private Account account;
 
   AccountProperties(
-      Account.Id accountId,
-      Timestamp registeredOn,
-      Config accountConfig,
-      @Nullable ObjectId metaId) {
+      Account.Id accountId, Instant registeredOn, Config accountConfig, @Nullable ObjectId metaId) {
     this.accountId = accountId;
     this.registeredOn = registeredOn;
     this.accountConfig = accountConfig;
@@ -80,7 +77,7 @@
     return account;
   }
 
-  public Timestamp getRegisteredOn() {
+  public Instant getRegisteredOn() {
     return registeredOn;
   }
 
diff --git a/java/com/google/gerrit/server/account/AccountResolver.java b/java/com/google/gerrit/server/account/AccountResolver.java
index 68f5a85..8824d56 100644
--- a/java/com/google/gerrit/server/account/AccountResolver.java
+++ b/java/com/google/gerrit/server/account/AccountResolver.java
@@ -27,7 +27,6 @@
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Streams;
 import com.google.gerrit.entities.Account;
-import com.google.gerrit.extensions.restapi.AuthException;
 import com.google.gerrit.extensions.restapi.UnprocessableEntityException;
 import com.google.gerrit.index.Schema;
 import com.google.gerrit.server.CurrentUser;
@@ -443,9 +442,10 @@
       // more strict here.
       boolean canSeeSecondaryEmails = false;
       try {
-        permissionBackend.user(self.get()).check(GlobalPermission.MODIFY_ACCOUNT);
-        canSeeSecondaryEmails = true;
-      } catch (AuthException | PermissionBackendException e) {
+        if (permissionBackend.user(self.get()).test(GlobalPermission.MODIFY_ACCOUNT)) {
+          canSeeSecondaryEmails = true;
+        }
+      } catch (PermissionBackendException e) {
         // remains false
       }
       return accountQueryProvider.get().enforceVisibility(true)
@@ -538,12 +538,12 @@
    * @throws IOException if an error occurs.
    */
   public Result resolve(String input) throws ConfigInvalidException, IOException {
-    return searchImpl(input, searchers, visibilitySupplierCanSee(), accountActivityPredicate());
+    return searchImpl(input, searchers, this::canSeePredicate, AccountResolver::isActive);
   }
 
   public Result resolve(String input, Predicate<AccountState> accountActivityPredicate)
       throws ConfigInvalidException, IOException {
-    return searchImpl(input, searchers, visibilitySupplierCanSee(), accountActivityPredicate);
+    return searchImpl(input, searchers, this::canSeePredicate, accountActivityPredicate);
   }
 
   /**
@@ -556,17 +556,17 @@
    * instead will be stored as a link to the corresponding Gerrit Account.
    */
   public Result resolveIncludeInactive(String input) throws ConfigInvalidException, IOException {
-    return searchImpl(input, searchers, visibilitySupplierCanSee(), all());
+    return searchImpl(input, searchers, this::canSeePredicate, AccountResolver::allVisible);
   }
 
   public Result resolveIgnoreVisibility(String input) throws ConfigInvalidException, IOException {
-    return searchImpl(input, searchers, visibilitySupplierAll(), accountActivityPredicate());
+    return searchImpl(input, searchers, this::allVisiblePredicate, AccountResolver::isActive);
   }
 
   public Result resolveIgnoreVisibility(
       String input, Predicate<AccountState> accountActivityPredicate)
       throws ConfigInvalidException, IOException {
-    return searchImpl(input, searchers, visibilitySupplierAll(), accountActivityPredicate);
+    return searchImpl(input, searchers, this::allVisiblePredicate, accountActivityPredicate);
   }
 
   /**
@@ -595,7 +595,7 @@
   @Deprecated
   public Result resolveByNameOrEmail(String input) throws ConfigInvalidException, IOException {
     return searchImpl(
-        input, nameOrEmailSearchers, visibilitySupplierCanSee(), accountActivityPredicate());
+        input, nameOrEmailSearchers, this::canSeePredicate, AccountResolver::isActive);
   }
 
   /**
@@ -614,26 +614,29 @@
     return searchImpl(
         input,
         ImmutableList.of(new ByNameAndEmail(), new ByEmail(), new ByFullName(), new ByUsername()),
-        visibilitySupplierCanSee(),
-        accountActivityPredicate());
+        this::canSeePredicate,
+        AccountResolver::isActive);
   }
 
-  private Supplier<Predicate<AccountState>> visibilitySupplierCanSee() {
-    return () -> accountControlFactory.get()::canSee;
+  private Predicate<AccountState> canSeePredicate() {
+    return this::canSee;
   }
 
-  private Supplier<Predicate<AccountState>> visibilitySupplierAll() {
-    return () -> all();
+  private boolean canSee(AccountState accountState) {
+    return accountControlFactory.get().canSee(accountState);
   }
 
-  private Predicate<AccountState> all() {
-    return accountState -> {
-      return true;
-    };
+  private Predicate<AccountState> allVisiblePredicate() {
+    return AccountResolver::allVisible;
   }
 
-  private Predicate<AccountState> accountActivityPredicate() {
-    return (AccountState accountState) -> accountState.account().isActive();
+  /** @param accountState account state for which the visibility should be checked */
+  private static boolean allVisible(AccountState accountState) {
+    return true;
+  }
+
+  private static boolean isActive(AccountState accountState) {
+    return accountState.account().isActive();
   }
 
   @VisibleForTesting
diff --git a/java/com/google/gerrit/server/account/AccountResource.java b/java/com/google/gerrit/server/account/AccountResource.java
index 4fb69bd..9629809 100644
--- a/java/com/google/gerrit/server/account/AccountResource.java
+++ b/java/com/google/gerrit/server/account/AccountResource.java
@@ -23,20 +23,16 @@
 import java.util.Set;
 
 public class AccountResource implements RestResource {
-  public static final TypeLiteral<RestView<AccountResource>> ACCOUNT_KIND =
-      new TypeLiteral<RestView<AccountResource>>() {};
+  public static final TypeLiteral<RestView<AccountResource>> ACCOUNT_KIND = new TypeLiteral<>() {};
 
-  public static final TypeLiteral<RestView<Capability>> CAPABILITY_KIND =
-      new TypeLiteral<RestView<Capability>>() {};
+  public static final TypeLiteral<RestView<Capability>> CAPABILITY_KIND = new TypeLiteral<>() {};
 
-  public static final TypeLiteral<RestView<Email>> EMAIL_KIND =
-      new TypeLiteral<RestView<Email>>() {};
+  public static final TypeLiteral<RestView<Email>> EMAIL_KIND = new TypeLiteral<>() {};
 
-  public static final TypeLiteral<RestView<SshKey>> SSH_KEY_KIND =
-      new TypeLiteral<RestView<SshKey>>() {};
+  public static final TypeLiteral<RestView<SshKey>> SSH_KEY_KIND = new TypeLiteral<>() {};
 
   public static final TypeLiteral<RestView<StarredChange>> STARRED_CHANGE_KIND =
-      new TypeLiteral<RestView<StarredChange>>() {};
+      new TypeLiteral<>() {};
 
   private final IdentifiedUser user;
 
@@ -106,8 +102,7 @@
   }
 
   public static class Star implements RestResource {
-    public static final TypeLiteral<RestView<Star>> STAR_KIND =
-        new TypeLiteral<RestView<Star>>() {};
+    public static final TypeLiteral<RestView<Star>> STAR_KIND = new TypeLiteral<>() {};
 
     private final IdentifiedUser user;
     private final ChangeResource change;
diff --git a/java/com/google/gerrit/server/account/AccountTagProvider.java b/java/com/google/gerrit/server/account/AccountTagProvider.java
index ddb1331..e74bde7 100644
--- a/java/com/google/gerrit/server/account/AccountTagProvider.java
+++ b/java/com/google/gerrit/server/account/AccountTagProvider.java
@@ -1,3 +1,17 @@
+// Copyright (C) 2021 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package com.google.gerrit.server.account;
 
 import com.google.gerrit.entities.Account;
diff --git a/java/com/google/gerrit/server/account/AccountsUpdate.java b/java/com/google/gerrit/server/account/AccountsUpdate.java
index 93738b0..3ee6365 100644
--- a/java/com/google/gerrit/server/account/AccountsUpdate.java
+++ b/java/com/google/gerrit/server/account/AccountsUpdate.java
@@ -49,7 +49,6 @@
 import com.google.inject.assistedinject.Assisted;
 import com.google.inject.assistedinject.AssistedInject;
 import java.io.IOException;
-import java.sql.Timestamp;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Objects;
@@ -201,8 +200,6 @@
   /** Single instance that accumulates updates from the batch. */
   private ExternalIdNotes externalIdNotes;
 
-  private static final Runnable DO_NOTHING = () -> {};
-
   @AssistedInject
   @SuppressWarnings("BindingAnnotationWithoutInject")
   AccountsUpdate(
@@ -225,8 +222,8 @@
         extIdNotesLoader,
         serverIdent,
         createPersonIdent(serverIdent, Optional.empty()),
-        DO_NOTHING,
-        DO_NOTHING);
+        AccountsUpdate::doNothing,
+        AccountsUpdate::doNothing);
   }
 
   @AssistedInject
@@ -252,8 +249,8 @@
         extIdNotesLoader,
         serverIdent,
         createPersonIdent(serverIdent, Optional.of(currentUser)),
-        DO_NOTHING,
-        DO_NOTHING);
+        AccountsUpdate::doNothing,
+        AccountsUpdate::doNothing);
   }
 
   @VisibleForTesting
@@ -297,9 +294,7 @@
 
   private static PersonIdent createPersonIdent(
       PersonIdent serverIdent, Optional<IdentifiedUser> user) {
-    return user.isPresent()
-        ? user.get().newCommitterIdent(serverIdent.getWhen(), serverIdent.getTimeZone())
-        : serverIdent;
+    return user.isPresent() ? user.get().newCommitterIdent(serverIdent) : serverIdent;
   }
 
   /**
@@ -324,6 +319,9 @@
    * @throws IOException if creating the user branch fails due to an IO error
    * @throws ConfigInvalidException if any of the account fields has an invalid value
    */
+  // TODO(issue-15517): Fix the JdkObsolete issue with Date once JGit's PersonIdent class supports
+  // Instants
+  @SuppressWarnings("JdkObsolete")
   public AccountState insert(String message, Account.Id accountId, ConfigureDeltaFromState init)
       throws IOException, ConfigInvalidException {
     return execute(
@@ -331,8 +329,7 @@
                 repo -> {
                   AccountConfig accountConfig = read(repo, accountId);
                   Account account =
-                      accountConfig.getNewAccount(
-                          new Timestamp(committerIdent.getWhen().getTime()));
+                      accountConfig.getNewAccount(committerIdent.getWhen().toInstant());
                   AccountState accountState = AccountState.forAccount(account);
                   AccountDelta.Builder deltaBuilder = AccountDelta.builder();
                   init.configure(accountState, deltaBuilder);
@@ -586,6 +583,8 @@
     return metaDataUpdate;
   }
 
+  private static void doNothing() {}
+
   @FunctionalInterface
   private interface ExecutableUpdate {
     UpdatedAccount execute(Repository allUsersRepo) throws IOException, ConfigInvalidException;
diff --git a/java/com/google/gerrit/server/account/AuthRequest.java b/java/com/google/gerrit/server/account/AuthRequest.java
index 50ed532..cceda70 100644
--- a/java/com/google/gerrit/server/account/AuthRequest.java
+++ b/java/com/google/gerrit/server/account/AuthRequest.java
@@ -49,20 +49,20 @@
     }
 
     /** Create a request for a local username, such as from LDAP. */
-    public AuthRequest createForUser(String username) {
+    public AuthRequest createForUser(String userName) {
       AuthRequest r =
           new AuthRequest(
-              externalIdKeyFactory.create(SCHEME_GERRIT, username), externalIdKeyFactory);
-      r.setUserName(username);
+              externalIdKeyFactory.create(SCHEME_GERRIT, userName), externalIdKeyFactory);
+      r.setUserName(userName);
       return r;
     }
 
     /** Create a request for an external username. */
-    public AuthRequest createForExternalUser(String username) {
+    public AuthRequest createForExternalUser(String userName) {
       AuthRequest r =
           new AuthRequest(
-              externalIdKeyFactory.create(SCHEME_EXTERNAL, username), externalIdKeyFactory);
-      r.setUserName(username);
+              externalIdKeyFactory.create(SCHEME_EXTERNAL, userName), externalIdKeyFactory);
+      r.setUserName(userName);
       return r;
     }
 
diff --git a/java/com/google/gerrit/server/account/CachedAccountDetails.java b/java/com/google/gerrit/server/account/CachedAccountDetails.java
index f23a766..2ab6174 100644
--- a/java/com/google/gerrit/server/account/CachedAccountDetails.java
+++ b/java/com/google/gerrit/server/account/CachedAccountDetails.java
@@ -30,7 +30,6 @@
 import com.google.gerrit.server.cache.serialize.CacheSerializer;
 import com.google.gerrit.server.cache.serialize.ObjectIdConverter;
 import com.google.gerrit.server.config.CachedPreferences;
-import java.sql.Timestamp;
 import java.time.Instant;
 import java.util.Map;
 import org.eclipse.jgit.lib.ObjectId;
@@ -107,7 +106,7 @@
       Cache.AccountProto.Builder accountProto =
           Cache.AccountProto.newBuilder()
               .setId(account.id().get())
-              .setRegisteredOn(account.registeredOn().toInstant().toEpochMilli())
+              .setRegisteredOn(account.registeredOn().toEpochMilli())
               .setInactive(account.inactive())
               .setFullName(Strings.nullToEmpty(account.fullName()))
               .setDisplayName(Strings.nullToEmpty(account.displayName()))
@@ -143,7 +142,7 @@
       Account account =
           Account.builder(
                   Account.id(proto.getAccount().getId()),
-                  Timestamp.from(Instant.ofEpochMilli(proto.getAccount().getRegisteredOn())))
+                  Instant.ofEpochMilli(proto.getAccount().getRegisteredOn()))
               .setFullName(Strings.emptyToNull(proto.getAccount().getFullName()))
               .setDisplayName(Strings.emptyToNull(proto.getAccount().getDisplayName()))
               .setPreferredEmail(Strings.emptyToNull(proto.getAccount().getPreferredEmail()))
diff --git a/java/com/google/gerrit/server/account/Emails.java b/java/com/google/gerrit/server/account/Emails.java
index 98d0d50..45f0844 100644
--- a/java/com/google/gerrit/server/account/Emails.java
+++ b/java/com/google/gerrit/server/account/Emails.java
@@ -29,7 +29,6 @@
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
 import java.io.IOException;
-import java.sql.Timestamp;
 import java.util.Arrays;
 import java.util.List;
 import java.util.Set;
@@ -114,11 +113,14 @@
     return externalIds.byEmail(email).stream().map(ExternalId::accountId).collect(toImmutableSet());
   }
 
+  // TODO(issue-15517): Fix the JdkObsolete issue with Date once JGit's PersonIdent class supports
+  // Instants
+  @SuppressWarnings("JdkObsolete")
   public UserIdentity toUserIdentity(PersonIdent who) throws IOException {
     UserIdentity u = new UserIdentity();
     u.setName(who.getName());
     u.setEmail(who.getEmailAddress());
-    u.setDate(new Timestamp(who.getWhen().getTime()));
+    u.setDate(who.getWhen().toInstant());
     u.setTimeZone(who.getTimeZoneOffset());
 
     // If only one account has access to this email address, select it
diff --git a/java/com/google/gerrit/server/account/GroupControl.java b/java/com/google/gerrit/server/account/GroupControl.java
index d42db60..fd18d3e 100644
--- a/java/com/google/gerrit/server/account/GroupControl.java
+++ b/java/com/google/gerrit/server/account/GroupControl.java
@@ -19,7 +19,6 @@
 import com.google.gerrit.entities.AccountGroup;
 import com.google.gerrit.entities.GroupDescription;
 import com.google.gerrit.exceptions.NoSuchGroupException;
-import com.google.gerrit.extensions.restapi.AuthException;
 import com.google.gerrit.server.CurrentUser;
 import com.google.gerrit.server.permissions.GlobalPermission;
 import com.google.gerrit.server.permissions.PermissionBackend;
@@ -189,10 +188,7 @@
 
   private boolean canAdministrateServer() {
     try {
-      perm.check(GlobalPermission.ADMINISTRATE_SERVER);
-      return true;
-    } catch (AuthException e) {
-      return false;
+      return perm.test(GlobalPermission.ADMINISTRATE_SERVER);
     } catch (PermissionBackendException e) {
       logger.atFine().log(
           "Failed to check %s global capability for user %s",
diff --git a/java/com/google/gerrit/server/account/Realm.java b/java/com/google/gerrit/server/account/Realm.java
index 3f642f7..ffc95a3 100644
--- a/java/com/google/gerrit/server/account/Realm.java
+++ b/java/com/google/gerrit/server/account/Realm.java
@@ -56,7 +56,14 @@
    */
   Account.Id lookup(String accountName) throws IOException;
 
-  /** Returns true if the account is active. */
+  /**
+   * Returns true if the account is active.
+   *
+   * @throws LoginException thrown if login is required and fails
+   * @throws NamingException may be thrown if the name is invalid
+   * @throws AccountException may be thrown in case the username is ambiguous
+   * @throws IOException thrown in case of IO errors
+   */
   default boolean isActive(@SuppressWarnings("unused") String username)
       throws LoginException, NamingException, AccountException, IOException {
     return true;
diff --git a/java/com/google/gerrit/server/account/SetInactiveFlag.java b/java/com/google/gerrit/server/account/SetInactiveFlag.java
index 4b68198..5babebd 100644
--- a/java/com/google/gerrit/server/account/SetInactiveFlag.java
+++ b/java/com/google/gerrit/server/account/SetInactiveFlag.java
@@ -55,26 +55,30 @@
       throws RestApiException, IOException, ConfigInvalidException {
     AtomicBoolean alreadyInactive = new AtomicBoolean(false);
     AtomicReference<Optional<RestApiException>> exception = new AtomicReference<>(Optional.empty());
-    accountsUpdateProvider
-        .get()
-        .update(
-            "Deactivate Account via API",
-            accountId,
-            (a, u) -> {
-              if (!a.account().isActive()) {
-                alreadyInactive.set(true);
-              } else {
-                try {
-                  accountActivationValidationListeners.runEach(
-                      l -> l.validateDeactivation(a), ValidationException.class);
-                } catch (ValidationException e) {
-                  exception.set(Optional.of(new ResourceConflictException(e.getMessage(), e)));
-                  return;
-                }
-                u.setActive(false);
-              }
-            })
-        .orElseThrow(() -> new ResourceNotFoundException("account not found"));
+    Optional<AccountState> updatedAccount =
+        accountsUpdateProvider
+            .get()
+            .update(
+                "Deactivate Account via API",
+                accountId,
+                (a, u) -> {
+                  if (!a.account().isActive()) {
+                    alreadyInactive.set(true);
+                  } else {
+                    try {
+                      accountActivationValidationListeners.runEach(
+                          l -> l.validateDeactivation(a), ValidationException.class);
+                    } catch (ValidationException e) {
+                      exception.set(Optional.of(new ResourceConflictException(e.getMessage(), e)));
+                      return;
+                    }
+                    u.setActive(false);
+                  }
+                });
+    if (!updatedAccount.isPresent()) {
+      throw new ResourceNotFoundException("account not found");
+    }
+
     if (exception.get().isPresent()) {
       throw exception.get().get();
     }
@@ -94,26 +98,30 @@
       throws RestApiException, IOException, ConfigInvalidException {
     AtomicBoolean alreadyActive = new AtomicBoolean(false);
     AtomicReference<Optional<RestApiException>> exception = new AtomicReference<>(Optional.empty());
-    accountsUpdateProvider
-        .get()
-        .update(
-            "Activate Account via API",
-            accountId,
-            (a, u) -> {
-              if (a.account().isActive()) {
-                alreadyActive.set(true);
-              } else {
-                try {
-                  accountActivationValidationListeners.runEach(
-                      l -> l.validateActivation(a), ValidationException.class);
-                } catch (ValidationException e) {
-                  exception.set(Optional.of(new ResourceConflictException(e.getMessage(), e)));
-                  return;
-                }
-                u.setActive(true);
-              }
-            })
-        .orElseThrow(() -> new ResourceNotFoundException("account not found"));
+    Optional<AccountState> updatedAccount =
+        accountsUpdateProvider
+            .get()
+            .update(
+                "Activate Account via API",
+                accountId,
+                (a, u) -> {
+                  if (a.account().isActive()) {
+                    alreadyActive.set(true);
+                  } else {
+                    try {
+                      accountActivationValidationListeners.runEach(
+                          l -> l.validateActivation(a), ValidationException.class);
+                    } catch (ValidationException e) {
+                      exception.set(Optional.of(new ResourceConflictException(e.getMessage(), e)));
+                      return;
+                    }
+                    u.setActive(true);
+                  }
+                });
+    if (!updatedAccount.isPresent()) {
+      throw new ResourceNotFoundException("account not found");
+    }
+
     if (exception.get().isPresent()) {
       throw exception.get().get();
     }
diff --git a/java/com/google/gerrit/server/account/externalids/DisabledExternalIdCache.java b/java/com/google/gerrit/server/account/externalids/DisabledExternalIdCache.java
index 1cd3de8..2d1ec1a 100644
--- a/java/com/google/gerrit/server/account/externalids/DisabledExternalIdCache.java
+++ b/java/com/google/gerrit/server/account/externalids/DisabledExternalIdCache.java
@@ -20,7 +20,6 @@
 import com.google.inject.AbstractModule;
 import com.google.inject.Module;
 import java.io.IOException;
-import java.util.Collection;
 import java.util.Optional;
 import org.eclipse.jgit.lib.ObjectId;
 
@@ -36,13 +35,6 @@
   }
 
   @Override
-  public void onReplace(
-      ObjectId oldNotesRev,
-      ObjectId newNotesRev,
-      Collection<ExternalId> toRemove,
-      Collection<ExternalId> toAdd) {}
-
-  @Override
   public Optional<ExternalId> byKey(ExternalId.Key key) throws IOException {
     throw new UnsupportedOperationException();
   }
diff --git a/java/com/google/gerrit/server/account/externalids/ExternalId.java b/java/com/google/gerrit/server/account/externalids/ExternalId.java
index 0a23a10..0a51171 100644
--- a/java/com/google/gerrit/server/account/externalids/ExternalId.java
+++ b/java/com/google/gerrit/server/account/externalids/ExternalId.java
@@ -310,7 +310,7 @@
     ExternalId o = (ExternalId) obj;
     return Objects.equals(key(), o.key())
         && Objects.equals(accountId(), o.accountId())
-        && Objects.equals(isCaseInsensitive(), o.isCaseInsensitive())
+        && isCaseInsensitive() == o.isCaseInsensitive()
         && Objects.equals(email(), o.email())
         && Objects.equals(password(), o.password());
   }
diff --git a/java/com/google/gerrit/server/account/externalids/ExternalIdCache.java b/java/com/google/gerrit/server/account/externalids/ExternalIdCache.java
index 0029557..9f766d0 100644
--- a/java/com/google/gerrit/server/account/externalids/ExternalIdCache.java
+++ b/java/com/google/gerrit/server/account/externalids/ExternalIdCache.java
@@ -18,7 +18,6 @@
 import com.google.common.collect.ImmutableSetMultimap;
 import com.google.gerrit.entities.Account;
 import java.io.IOException;
-import java.util.Collection;
 import java.util.Optional;
 import org.eclipse.jgit.lib.ObjectId;
 
@@ -32,21 +31,6 @@
  * <p>All returned collections are unmodifiable.
  */
 interface ExternalIdCache {
-
-  /**
-   * Updates the cache.
-   *
-   * @param oldNotesRev current revision against which the below updates are applied
-   * @param newNotesRev key for the new cache revision
-   * @param toRemove external IDs to remove
-   * @param toAdd external IDs to add
-   */
-  void onReplace(
-      ObjectId oldNotesRev,
-      ObjectId newNotesRev,
-      Collection<ExternalId> toRemove,
-      Collection<ExternalId> toAdd);
-
   Optional<ExternalId> byKey(ExternalId.Key key) throws IOException;
 
   ImmutableSet<ExternalId> byAccount(Account.Id accountId) throws IOException;
diff --git a/java/com/google/gerrit/server/account/externalids/ExternalIdCacheImpl.java b/java/com/google/gerrit/server/account/externalids/ExternalIdCacheImpl.java
index e6db593..af8e19f 100644
--- a/java/com/google/gerrit/server/account/externalids/ExternalIdCacheImpl.java
+++ b/java/com/google/gerrit/server/account/externalids/ExternalIdCacheImpl.java
@@ -14,66 +14,42 @@
 
 package com.google.gerrit.server.account.externalids;
 
-import com.google.common.cache.LoadingCache;
+import com.google.common.cache.Cache;
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.ImmutableSetMultimap;
-import com.google.common.collect.MultimapBuilder;
-import com.google.common.collect.SetMultimap;
-import com.google.common.flogger.FluentLogger;
 import com.google.gerrit.entities.Account;
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
 import com.google.inject.name.Named;
 import java.io.IOException;
-import java.util.Collection;
 import java.util.Optional;
-import java.util.concurrent.ExecutionException;
 import java.util.concurrent.locks.Lock;
 import java.util.concurrent.locks.ReentrantLock;
-import java.util.function.Consumer;
+import org.eclipse.jgit.errors.ConfigInvalidException;
 import org.eclipse.jgit.lib.ObjectId;
 
 /** Caches external IDs of all accounts. The external IDs are always loaded from NoteDb. */
 @Singleton
 class ExternalIdCacheImpl implements ExternalIdCache {
-  private static final FluentLogger logger = FluentLogger.forEnclosingClass();
-
   public static final String CACHE_NAME = "external_ids_map";
 
-  private final LoadingCache<ObjectId, AllExternalIds> extIdsByAccount;
+  private final Cache<ObjectId, AllExternalIds> extIdsByAccount;
   private final ExternalIdReader externalIdReader;
+  private final ExternalIdCacheLoader externalIdCacheLoader;
   private final Lock lock;
 
   @Inject
   ExternalIdCacheImpl(
-      @Named(CACHE_NAME) LoadingCache<ObjectId, AllExternalIds> extIdsByAccount,
-      ExternalIdReader externalIdReader) {
+      @Named(CACHE_NAME) Cache<ObjectId, AllExternalIds> extIdsByAccount,
+      ExternalIdReader externalIdReader,
+      ExternalIdCacheLoader externalIdCacheLoader) {
     this.extIdsByAccount = extIdsByAccount;
     this.externalIdReader = externalIdReader;
+    this.externalIdCacheLoader = externalIdCacheLoader;
     this.lock = new ReentrantLock(true /* fair */);
   }
 
   @Override
-  public void onReplace(
-      ObjectId oldNotesRev,
-      ObjectId newNotesRev,
-      Collection<ExternalId> toRemove,
-      Collection<ExternalId> toAdd) {
-    updateCache(
-        oldNotesRev,
-        newNotesRev,
-        m -> {
-          for (ExternalId extId : toRemove) {
-            m.remove(extId.accountId(), extId);
-          }
-          for (ExternalId extId : toAdd) {
-            extId.checkThatBlobIdIsSet();
-            m.put(extId.accountId(), extId);
-          }
-        });
-  }
-
-  @Override
   public Optional<ExternalId> byKey(ExternalId.Key key) throws IOException {
     return Optional.ofNullable(get().byKey().get(key));
   }
@@ -112,38 +88,39 @@
     return get(externalIdReader.readRevision());
   }
 
+  /**
+   * Returns the cached value or a freshly loaded value that will be cached with this call in case
+   * the value was absent from the cache.
+   *
+   * <p>This method will load the value using {@link ExternalIdCacheLoader} in case it is not
+   * already cached. {@link ExternalIdCacheLoader} requires loading older versions of the cached
+   * value and Caffeine does not support recursive calls to the cache from loaders. Hence, we use a
+   * Cache instead of a LoadingCache and perform the loading ourselves here similar to what a
+   * loading cache would do.
+   */
   private AllExternalIds get(ObjectId rev) throws IOException {
-    try {
-      return extIdsByAccount.get(rev);
-    } catch (ExecutionException e) {
-      throw new IOException("Cannot load external ids", e);
-    }
-  }
-
-  private void updateCache(
-      ObjectId oldNotesRev,
-      ObjectId newNotesRev,
-      Consumer<SetMultimap<Account.Id, ExternalId>> update) {
-    if (oldNotesRev.equals(newNotesRev)) {
-      // No need to update external id cache since there is no update to those external ids.
-      return;
+    AllExternalIds cachedValue = extIdsByAccount.getIfPresent(rev);
+    if (cachedValue != null) {
+      return cachedValue;
     }
 
+    // Load the value and put it in the cache.
     lock.lock();
     try {
-      SetMultimap<Account.Id, ExternalId> m;
-      if (!ObjectId.zeroId().equals(oldNotesRev)) {
-        m =
-            MultimapBuilder.hashKeys()
-                .hashSetValues()
-                .build(extIdsByAccount.get(oldNotesRev).byAccount());
-      } else {
-        m = MultimapBuilder.hashKeys().hashSetValues().build();
+      // Check if value was already loaded while waiting for the lock.
+      cachedValue = extIdsByAccount.getIfPresent(rev);
+      if (cachedValue != null) {
+        return cachedValue;
       }
-      update.accept(m);
-      extIdsByAccount.put(newNotesRev, AllExternalIds.create(m.values().stream()));
-    } catch (ExecutionException e) {
-      logger.atWarning().withCause(e).log("Cannot update external IDs");
+
+      AllExternalIds newlyLoadedValue;
+      try {
+        newlyLoadedValue = externalIdCacheLoader.load(rev);
+      } catch (ConfigInvalidException e) {
+        throw new IOException("Cannot load external ids", e);
+      }
+      extIdsByAccount.put(rev, newlyLoadedValue);
+      return newlyLoadedValue;
     } finally {
       lock.unlock();
     }
diff --git a/java/com/google/gerrit/server/account/externalids/ExternalIdCacheLoader.java b/java/com/google/gerrit/server/account/externalids/ExternalIdCacheLoader.java
index 72d703b..27672bd 100644
--- a/java/com/google/gerrit/server/account/externalids/ExternalIdCacheLoader.java
+++ b/java/com/google/gerrit/server/account/externalids/ExternalIdCacheLoader.java
@@ -16,7 +16,6 @@
 
 import com.google.common.base.CharMatcher;
 import com.google.common.cache.Cache;
-import com.google.common.cache.CacheLoader;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.ImmutableSetMultimap;
@@ -36,7 +35,6 @@
 import com.google.gerrit.server.logging.TraceContext;
 import com.google.gerrit.server.logging.TraceContext.TraceTimer;
 import com.google.inject.Inject;
-import com.google.inject.Provider;
 import com.google.inject.Singleton;
 import com.google.inject.name.Named;
 import java.io.IOException;
@@ -58,7 +56,7 @@
 
 /** Loads cache values for the external ID cache using either a full or a partial reload. */
 @Singleton
-public class ExternalIdCacheLoader extends CacheLoader<ObjectId, AllExternalIds> {
+public class ExternalIdCacheLoader {
   private static final FluentLogger logger = FluentLogger.forEnclosingClass();
 
   // Maximum number of prior states we inspect to find a base for differential. If no cached state
@@ -66,12 +64,11 @@
   private static final int MAX_HISTORY_LOOKBACK = 10;
 
   private final ExternalIdReader externalIdReader;
-  private final Provider<Cache<ObjectId, AllExternalIds>> externalIdCache;
+  private final Cache<ObjectId, AllExternalIds> externalIdCache;
   private final GitRepositoryManager gitRepositoryManager;
   private final AllUsersName allUsersName;
   private final Counter1<Boolean> reloadCounter;
   private final Timer0 reloadDifferential;
-  private final boolean enablePartialReloads;
   private final boolean isPersistentCache;
   private final ExternalIdFactory externalIdFactory;
 
@@ -80,8 +77,7 @@
       GitRepositoryManager gitRepositoryManager,
       AllUsersName allUsersName,
       ExternalIdReader externalIdReader,
-      @Named(ExternalIdCacheImpl.CACHE_NAME)
-          Provider<Cache<ObjectId, AllExternalIds>> externalIdCache,
+      @Named(ExternalIdCacheImpl.CACHE_NAME) Cache<ObjectId, AllExternalIds> externalIdCache,
       MetricMaker metricMaker,
       @GerritServerConfig Config config,
       ExternalIdFactory externalIdFactory) {
@@ -105,23 +101,13 @@
                     "Latency for generating a new external ID cache state from a prior state.")
                 .setCumulative()
                 .setUnit(Units.MILLISECONDS));
-    this.enablePartialReloads =
-        config.getBoolean("cache", ExternalIdCacheImpl.CACHE_NAME, "enablePartialReloads", true);
     this.isPersistentCache =
         config.getInt("cache", ExternalIdCacheImpl.CACHE_NAME, "diskLimit", 0) > 0;
     this.externalIdFactory = externalIdFactory;
   }
 
-  @Override
   public AllExternalIds load(ObjectId notesRev) throws IOException, ConfigInvalidException {
-    if (!enablePartialReloads) {
-      logger.atInfo().log(
-          "Partial reloads of "
-              + ExternalIdCacheImpl.CACHE_NAME
-              + " disabled. Falling back to full reload.");
-      return reloadAllExternalIds(notesRev);
-    }
-
+    externalIdReader.checkReadEnabled();
     // The requested value was not in the cache (hence, this loader was invoked). Therefore, try to
     // create this entry from a past value using the minimal amount of Git operations possible to
     // reduce latency.
@@ -158,7 +144,7 @@
       while ((parentWithCacheValue = rw.next()) != null
           && i++ < MAX_HISTORY_LOOKBACK
           && parentWithCacheValue.getParentCount() < 2) {
-        oldExternalIds = externalIdCache.get().getIfPresent(parentWithCacheValue.getId());
+        oldExternalIds = externalIdCache.getIfPresent(parentWithCacheValue.getId());
         if (oldExternalIds != null) {
           // We found a previously cached state.
           break;
diff --git a/java/com/google/gerrit/server/account/externalids/ExternalIdCacheModule.java b/java/com/google/gerrit/server/account/externalids/ExternalIdCacheModule.java
index f0ad1b2..1873ea0 100644
--- a/java/com/google/gerrit/server/account/externalids/ExternalIdCacheModule.java
+++ b/java/com/google/gerrit/server/account/externalids/ExternalIdCacheModule.java
@@ -35,7 +35,6 @@
         // Guava calls the loader first and evicts later on.
         .maximumWeight(2)
         .expireFromMemoryAfterAccess(Duration.ofMinutes(1))
-        .loader(ExternalIdCacheLoader.class)
         .diskLimit(-1)
         .version(1)
         .keySerializer(ObjectIdCacheSerializer.INSTANCE)
diff --git a/java/com/google/gerrit/server/account/externalids/ExternalIdCaseSensitivityMigrator.java b/java/com/google/gerrit/server/account/externalids/ExternalIdCaseSensitivityMigrator.java
index a59e935..a6ee366c 100644
--- a/java/com/google/gerrit/server/account/externalids/ExternalIdCaseSensitivityMigrator.java
+++ b/java/com/google/gerrit/server/account/externalids/ExternalIdCaseSensitivityMigrator.java
@@ -127,11 +127,11 @@
                   isUserNameCaseInsensitive ? "" : "in"));
           extIdNotes.commit(metaDataUpdate);
         } catch (Exception e) {
-          logger.atSevere().withCause(e).log(e.getMessage());
+          logger.atSevere().withCause(e).log("%s", e.getMessage());
         }
       }
     } catch (DuplicateExternalIdKeyException e) {
-      logger.atSevere().withCause(e).log(e.getMessage());
+      logger.atSevere().withCause(e).log("%s", e.getMessage());
       throw e;
     }
   }
diff --git a/java/com/google/gerrit/server/account/externalids/ExternalIdFactory.java b/java/com/google/gerrit/server/account/externalids/ExternalIdFactory.java
index bd9c7df..b16f73f 100644
--- a/java/com/google/gerrit/server/account/externalids/ExternalIdFactory.java
+++ b/java/com/google/gerrit/server/account/externalids/ExternalIdFactory.java
@@ -19,7 +19,6 @@
 
 import com.google.common.base.Strings;
 import com.google.common.collect.Iterables;
-import com.google.common.flogger.FluentLogger;
 import com.google.gerrit.common.Nullable;
 import com.google.gerrit.entities.Account;
 import com.google.gerrit.server.account.HashedPassword;
@@ -33,7 +32,6 @@
 
 @Singleton
 public class ExternalIdFactory {
-  private static final FluentLogger logger = FluentLogger.forEnclosingClass();
   private final ExternalIdKeyFactory externalIdKeyFactory;
   private AuthConfig authConfig;
 
@@ -264,7 +262,8 @@
         throw invalidConfig(
             noteId,
             String.format(
-                "Neither case sensitive nor case insensitive SHA1 of external ID '%s' match note ID '%s'",
+                "Neither case sensitive nor case insensitive SHA1 of external ID '%s' match note ID"
+                    + " '%s'",
                 externalIdKeyStr, noteId));
       }
       externalIdKey =
@@ -316,15 +315,17 @@
       }
       return accountId;
     } catch (IllegalArgumentException e) {
-      String msg =
-          String.format(
-              "Value %s for '%s.%s.%s' is invalid, expected account ID",
-              accountIdStr,
-              ExternalId.EXTERNAL_ID_SECTION,
-              externalIdKeyStr,
-              ExternalId.ACCOUNT_ID_KEY);
-      logger.atSevere().withCause(e).log(msg);
-      throw invalidConfig(noteId, msg);
+      ConfigInvalidException newException =
+          invalidConfig(
+              noteId,
+              String.format(
+                  "Value %s for '%s.%s.%s' is invalid, expected account ID",
+                  accountIdStr,
+                  ExternalId.EXTERNAL_ID_SECTION,
+                  externalIdKeyStr,
+                  ExternalId.ACCOUNT_ID_KEY));
+      newException.initCause(e);
+      throw newException;
     }
   }
 
diff --git a/java/com/google/gerrit/server/account/externalids/ExternalIdNotes.java b/java/com/google/gerrit/server/account/externalids/ExternalIdNotes.java
index aa37451..b0618ba 100644
--- a/java/com/google/gerrit/server/account/externalids/ExternalIdNotes.java
+++ b/java/com/google/gerrit/server/account/externalids/ExternalIdNotes.java
@@ -167,17 +167,6 @@
         cacheUpdate.execute(updates);
       }
 
-      // Perform the cache update.
-      if (!externalIdNotes.noCacheUpdate) {
-        // Regardless of noCacheUpdate it's still possible that the ExternalIdCache instance is of
-        // type DisabledExternalIdCache, making this call a no-op.
-        externalIdCache.onReplace(
-            externalIdNotes.oldRev,
-            externalIdNotes.getRevision(),
-            updates.getRemoved(),
-            updates.getAdded());
-      }
-
       // Reindex accounts (if the subclass implements reindexAccount()).
       if (!externalIdNotes.noReindex) {
         Streams.concat(updates.getAdded().stream(), updates.getRemoved().stream())
@@ -331,14 +320,13 @@
             externalIdFactory,
             isUserNameCaseInsensitiveMigrationMode)
         .setReadOnly()
-        .setNoCacheUpdate()
         .setNoReindex()
         .load(rev);
   }
 
   /**
-   * Loads the external ID notes for updates without cache evictions. The external ID notes are
-   * loaded from the current tip of the {@code refs/meta/external-ids} branch.
+   * Loads the external ID notes for updates. The external ID notes are loaded from the current tip
+   * of the {@code refs/meta/external-ids} branch.
    *
    * <p>Use this only from init, schema upgrades and tests.
    *
@@ -346,7 +334,7 @@
    *
    * @return {@link ExternalIdNotes} instance that doesn't updates caches on save
    */
-  public static ExternalIdNotes loadNoCacheUpdate(
+  public static ExternalIdNotes load(
       AllUsersName allUsersName,
       Repository allUsersRepo,
       ExternalIdFactory externalIdFactory,
@@ -359,7 +347,6 @@
             DynamicMap.emptyMap(),
             externalIdFactory,
             isUserNameCaseInsensitiveMigrationMode)
-        .setNoCacheUpdate()
         .setNoReindex()
         .load();
   }
@@ -393,7 +380,6 @@
 
   private Runnable afterReadRevision;
   private boolean readOnly = false;
-  private boolean noCacheUpdate = false;
   private boolean noReindex = false;
   private boolean isUserNameCaseInsensitiveMigrationMode = false;
   protected final Function<ExternalId, ObjectId> defaultNoteIdResolver =
@@ -450,11 +436,6 @@
     return this;
   }
 
-  private ExternalIdNotes setNoCacheUpdate() {
-    noCacheUpdate = true;
-    return this;
-  }
-
   private ExternalIdNotes setNoReindex() {
     noReindex = true;
     return this;
diff --git a/java/com/google/gerrit/server/account/externalids/ExternalIdReader.java b/java/com/google/gerrit/server/account/externalids/ExternalIdReader.java
index e5aace0..fb7f6c4 100644
--- a/java/com/google/gerrit/server/account/externalids/ExternalIdReader.java
+++ b/java/com/google/gerrit/server/account/externalids/ExternalIdReader.java
@@ -103,6 +103,12 @@
     this.failOnLoad = failOnLoad;
   }
 
+  public void checkReadEnabled() throws IOException {
+    if (failOnLoad) {
+      throw new IOException("Reading from external IDs is disabled");
+    }
+  }
+
   ObjectId readRevision() throws IOException {
     try (Repository repo = repoManager.openRepository(allUsersName)) {
       return readRevision(repo);
@@ -182,10 +188,4 @@
           .get(key);
     }
   }
-
-  private void checkReadEnabled() throws IOException {
-    if (failOnLoad) {
-      throw new IOException("Reading from external IDs is disabled");
-    }
-  }
 }
diff --git a/java/com/google/gerrit/server/account/externalids/OnlineExternalIdCaseSensivityMigrator.java b/java/com/google/gerrit/server/account/externalids/OnlineExternalIdCaseSensivityMigrator.java
index e52991b..72e7e90 100644
--- a/java/com/google/gerrit/server/account/externalids/OnlineExternalIdCaseSensivityMigrator.java
+++ b/java/com/google/gerrit/server/account/externalids/OnlineExternalIdCaseSensivityMigrator.java
@@ -70,7 +70,9 @@
   public void migrate() {
     if (!isUserNameCaseInsensitive || !isUserNameCaseInsensitiveMigrationMode) {
       logger.atSevere().log(
-          "External IDs online migration requires auth.userNameCaseInsensitive and auth.userNameCaseInsensitiveMigrationMode to be set to true. Skipping migration!");
+          "External IDs online migration requires auth.userNameCaseInsensitive and"
+              + " auth.userNameCaseInsensitiveMigrationMode to be set to true. Skipping"
+              + " migration!");
       return;
     }
     executor.execute(
diff --git a/java/com/google/gerrit/server/api/changes/RevisionApiImpl.java b/java/com/google/gerrit/server/api/changes/RevisionApiImpl.java
index 764c46d..9aa9306 100644
--- a/java/com/google/gerrit/server/api/changes/RevisionApiImpl.java
+++ b/java/com/google/gerrit/server/api/changes/RevisionApiImpl.java
@@ -86,7 +86,6 @@
 import com.google.gerrit.server.restapi.change.ListRobotComments;
 import com.google.gerrit.server.restapi.change.Mergeable;
 import com.google.gerrit.server.restapi.change.PostReview;
-import com.google.gerrit.server.restapi.change.PreviewSubmit;
 import com.google.gerrit.server.restapi.change.PutDescription;
 import com.google.gerrit.server.restapi.change.Rebase;
 import com.google.gerrit.server.restapi.change.Reviewed;
@@ -119,7 +118,6 @@
   private final Rebase rebase;
   private final RebaseUtil rebaseUtil;
   private final Submit submit;
-  private final PreviewSubmit submitPreview;
   private final Reviewed.PutReviewed putReviewed;
   private final Reviewed.DeleteReviewed deleteReviewed;
   private final RevisionResource revision;
@@ -167,7 +165,6 @@
       Rebase rebase,
       RebaseUtil rebaseUtil,
       Submit submit,
-      PreviewSubmit submitPreview,
       Reviewed.PutReviewed putReviewed,
       Reviewed.DeleteReviewed deleteReviewed,
       Files files,
@@ -213,7 +210,6 @@
     this.rebaseUtil = rebaseUtil;
     this.review = review;
     this.submit = submit;
-    this.submitPreview = submitPreview;
     this.files = files;
     this.putReviewed = putReviewed;
     this.deleteReviewed = deleteReviewed;
@@ -270,16 +266,6 @@
   }
 
   @Override
-  public BinaryResult submitPreview(String format) throws RestApiException {
-    try {
-      submitPreview.setFormat(format);
-      return submitPreview.apply(revision).value();
-    } catch (Exception e) {
-      throw asRestApiException("Cannot get submit preview", e);
-    }
-  }
-
-  @Override
   public ChangeApi rebase(RebaseInput in) throws RestApiException {
     try {
       return changes.id(rebaseAsInfo(in)._number);
diff --git a/java/com/google/gerrit/server/api/projects/ProjectApiImpl.java b/java/com/google/gerrit/server/api/projects/ProjectApiImpl.java
index 9521759..5baed86 100644
--- a/java/com/google/gerrit/server/api/projects/ProjectApiImpl.java
+++ b/java/com/google/gerrit/server/api/projects/ProjectApiImpl.java
@@ -507,7 +507,7 @@
 
   @Override
   public ListRefsRequest<BranchInfo> branches() {
-    return new ListRefsRequest<BranchInfo>() {
+    return new ListRefsRequest<>() {
       @Override
       public List<BranchInfo> get() throws RestApiException {
         try {
@@ -521,7 +521,7 @@
 
   @Override
   public ListRefsRequest<TagInfo> tags() {
-    return new ListRefsRequest<TagInfo>() {
+    return new ListRefsRequest<>() {
       @Override
       public List<TagInfo> get() throws RestApiException {
         try {
diff --git a/java/com/google/gerrit/server/approval/ApprovalCache.java b/java/com/google/gerrit/server/approval/ApprovalCache.java
deleted file mode 100644
index 5637249..0000000
--- a/java/com/google/gerrit/server/approval/ApprovalCache.java
+++ /dev/null
@@ -1,28 +0,0 @@
-// Copyright (C) 2021 The Android Open Source Project
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package com.google.gerrit.server.approval;
-
-import com.google.gerrit.entities.PatchSet;
-import com.google.gerrit.entities.PatchSetApproval;
-import com.google.gerrit.server.notedb.ChangeNotes;
-
-/**
- * Cache that holds approvals per patch set and NoteDb state. This includes approvals copied forward
- * from older patch sets.
- */
-public interface ApprovalCache {
-  /** Returns {@link PatchSetApproval}s for the given patch set. */
-  Iterable<PatchSetApproval> get(ChangeNotes notes, PatchSet.Id psId);
-}
diff --git a/java/com/google/gerrit/server/approval/ApprovalCacheImpl.java b/java/com/google/gerrit/server/approval/ApprovalCacheImpl.java
deleted file mode 100644
index fd31da9..0000000
--- a/java/com/google/gerrit/server/approval/ApprovalCacheImpl.java
+++ /dev/null
@@ -1,133 +0,0 @@
-// Copyright (C) 2021 The Android Open Source Project
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package com.google.gerrit.server.approval;
-
-import com.google.common.cache.CacheLoader;
-import com.google.common.cache.LoadingCache;
-import com.google.common.collect.ImmutableList;
-import com.google.gerrit.entities.Change;
-import com.google.gerrit.entities.PatchSet;
-import com.google.gerrit.entities.PatchSetApproval;
-import com.google.gerrit.entities.Project;
-import com.google.gerrit.entities.converter.PatchSetApprovalProtoConverter;
-import com.google.gerrit.exceptions.StorageException;
-import com.google.gerrit.proto.Entities;
-import com.google.gerrit.server.cache.CacheModule;
-import com.google.gerrit.server.cache.proto.Cache;
-import com.google.gerrit.server.cache.serialize.ObjectIdCacheSerializer;
-import com.google.gerrit.server.cache.serialize.ProtobufSerializer;
-import com.google.gerrit.server.notedb.ChangeNotes;
-import com.google.inject.Inject;
-import com.google.inject.Module;
-import com.google.inject.Singleton;
-import com.google.inject.name.Named;
-import com.google.protobuf.ByteString;
-import java.util.concurrent.ExecutionException;
-
-/** Implementation of the {@link ApprovalCache} interface */
-public class ApprovalCacheImpl implements ApprovalCache {
-  private static final String CACHE_NAME = "approvals";
-
-  public static Module module() {
-    return new CacheModule() {
-      @Override
-      protected void configure() {
-        bind(ApprovalCache.class).to(ApprovalCacheImpl.class);
-        persist(
-                CACHE_NAME,
-                Cache.PatchSetApprovalsKeyProto.class,
-                Cache.AllPatchSetApprovalsProto.class)
-            .version(2)
-            .loader(Loader.class)
-            .keyS