diff --git a/java/com/google/gerrit/extensions/common/ActionInfo.java b/java/com/google/gerrit/extensions/common/ActionInfo.java
index 6ab80b2..8039949 100644
--- a/java/com/google/gerrit/extensions/common/ActionInfo.java
+++ b/java/com/google/gerrit/extensions/common/ActionInfo.java
@@ -15,6 +15,7 @@
 package com.google.gerrit.extensions.common;
 
 import com.google.gerrit.extensions.webui.UiAction;
+import java.util.Objects;
 
 /**
  * Representation of an action in the REST API.
@@ -55,4 +56,21 @@
     title = d.getTitle();
     enabled = d.isEnabled() ? true : null;
   }
+
+  @Override
+  public boolean equals(Object o) {
+    if (o instanceof ActionInfo) {
+      ActionInfo actionInfo = (ActionInfo) o;
+      return Objects.equals(method, actionInfo.method)
+          && Objects.equals(label, actionInfo.label)
+          && Objects.equals(title, actionInfo.title)
+          && Objects.equals(enabled, actionInfo.enabled);
+    }
+    return false;
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(method, label, title, enabled);
+  }
 }
diff --git a/java/com/google/gerrit/extensions/common/ApprovalInfo.java b/java/com/google/gerrit/extensions/common/ApprovalInfo.java
index f95ddff..bf72e83 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.util.Objects;
 
 /**
  * Representation of an approval in the REST API.
@@ -71,4 +72,23 @@
     this.date = date;
     this.tag = tag;
   }
+
+  @Override
+  public boolean equals(Object o) {
+    if (o instanceof ApprovalInfo) {
+      ApprovalInfo approvalInfo = (ApprovalInfo) o;
+      return super.equals(o)
+          && Objects.equals(tag, approvalInfo.tag)
+          && Objects.equals(value, approvalInfo.value)
+          && Objects.equals(date, approvalInfo.date)
+          && Objects.equals(postSubmit, approvalInfo.postSubmit)
+          && Objects.equals(permittedVotingRange, approvalInfo.permittedVotingRange);
+    }
+    return false;
+  }
+
+  @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 f29d32b..490d394 100644
--- a/java/com/google/gerrit/extensions/common/AttentionSetInfo.java
+++ b/java/com/google/gerrit/extensions/common/AttentionSetInfo.java
@@ -15,6 +15,7 @@
 package com.google.gerrit.extensions.common;
 
 import java.sql.Timestamp;
+import java.util.Objects;
 
 /**
  * Represents a single user included in the attention set. Used in the API. See {@link
@@ -36,4 +37,20 @@
     this.lastUpdate = lastUpdate;
     this.reason = reason;
   }
+
+  @Override
+  public boolean equals(Object o) {
+    if (o instanceof AttentionSetInfo) {
+      AttentionSetInfo attentionSetInfo = (AttentionSetInfo) o;
+      return Objects.equals(account, attentionSetInfo.account)
+          && Objects.equals(lastUpdate, attentionSetInfo.lastUpdate)
+          && Objects.equals(reason, attentionSetInfo.reason);
+    }
+    return false;
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(account, lastUpdate, reason);
+  }
 }
diff --git a/java/com/google/gerrit/extensions/common/AvatarInfo.java b/java/com/google/gerrit/extensions/common/AvatarInfo.java
index 75665a8..b620ac2 100644
--- a/java/com/google/gerrit/extensions/common/AvatarInfo.java
+++ b/java/com/google/gerrit/extensions/common/AvatarInfo.java
@@ -14,6 +14,8 @@
 
 package com.google.gerrit.extensions.common;
 
+import java.util.Objects;
+
 /**
  * Representation of an avatar in the REST API.
  *
@@ -38,4 +40,20 @@
 
   /** The width of the avatar image in pixels. */
   public Integer width;
+
+  @Override
+  public boolean equals(Object o) {
+    if (o instanceof AvatarInfo) {
+      AvatarInfo avatarInfo = (AvatarInfo) o;
+      return Objects.equals(url, avatarInfo.url)
+          && Objects.equals(height, avatarInfo.height)
+          && Objects.equals(width, avatarInfo.width);
+    }
+    return false;
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(url, height, width);
+  }
 }
diff --git a/java/com/google/gerrit/extensions/common/FetchInfo.java b/java/com/google/gerrit/extensions/common/FetchInfo.java
index eda84b1..472dba2 100644
--- a/java/com/google/gerrit/extensions/common/FetchInfo.java
+++ b/java/com/google/gerrit/extensions/common/FetchInfo.java
@@ -15,6 +15,7 @@
 package com.google.gerrit.extensions.common;
 
 import java.util.Map;
+import java.util.Objects;
 
 public class FetchInfo {
   public String url;
@@ -25,4 +26,20 @@
     this.url = url;
     this.ref = ref;
   }
+
+  @Override
+  public boolean equals(Object o) {
+    if (o instanceof FetchInfo) {
+      FetchInfo fetchInfo = (FetchInfo) o;
+      return Objects.equals(url, fetchInfo.url)
+          && Objects.equals(ref, fetchInfo.ref)
+          && Objects.equals(commands, fetchInfo.commands);
+    }
+    return false;
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(url, ref, commands);
+  }
 }
diff --git a/java/com/google/gerrit/extensions/common/GpgKeyInfo.java b/java/com/google/gerrit/extensions/common/GpgKeyInfo.java
index 7a5c15b..d656f22 100644
--- a/java/com/google/gerrit/extensions/common/GpgKeyInfo.java
+++ b/java/com/google/gerrit/extensions/common/GpgKeyInfo.java
@@ -15,6 +15,7 @@
 package com.google.gerrit.extensions.common;
 
 import java.util.List;
+import java.util.Objects;
 
 public class GpgKeyInfo {
   /**
@@ -43,4 +44,22 @@
 
   public Status status;
   public List<String> problems;
+
+  @Override
+  public boolean equals(Object o) {
+    if (o instanceof GpgKeyInfo) {
+      GpgKeyInfo gpgKeyInfo = (GpgKeyInfo) o;
+      return Objects.equals(id, gpgKeyInfo.id)
+          && Objects.equals(fingerprint, gpgKeyInfo.fingerprint)
+          && Objects.equals(userIds, gpgKeyInfo.userIds)
+          && Objects.equals(status, gpgKeyInfo.status)
+          && Objects.equals(problems, gpgKeyInfo.problems);
+    }
+    return false;
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(id, fingerprint, userIds, status, problems);
+  }
 }
diff --git a/java/com/google/gerrit/extensions/common/LabelInfo.java b/java/com/google/gerrit/extensions/common/LabelInfo.java
index 76dd93d..44bcdaf 100644
--- a/java/com/google/gerrit/extensions/common/LabelInfo.java
+++ b/java/com/google/gerrit/extensions/common/LabelInfo.java
@@ -16,6 +16,7 @@
 
 import java.util.List;
 import java.util.Map;
+import java.util.Objects;
 
 public class LabelInfo {
   public AccountInfo approved;
@@ -30,4 +31,37 @@
   public Short defaultValue;
   public Boolean optional;
   public Boolean blocking;
+
+  @Override
+  public boolean equals(Object o) {
+    if (o instanceof LabelInfo) {
+      LabelInfo labelInfo = (LabelInfo) o;
+      return Objects.equals(approved, labelInfo.approved)
+          && Objects.equals(rejected, labelInfo.rejected)
+          && Objects.equals(recommended, labelInfo.recommended)
+          && Objects.equals(disliked, labelInfo.disliked)
+          && Objects.equals(all, labelInfo.all)
+          && Objects.equals(values, labelInfo.values)
+          && Objects.equals(value, labelInfo.value)
+          && Objects.equals(defaultValue, labelInfo.defaultValue)
+          && Objects.equals(optional, labelInfo.optional)
+          && Objects.equals(blocking, labelInfo.blocking);
+    }
+    return false;
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(
+        approved,
+        rejected,
+        recommended,
+        disliked,
+        all,
+        values,
+        value,
+        defaultValue,
+        optional,
+        blocking);
+  }
 }
diff --git a/java/com/google/gerrit/extensions/common/PluginDefinedInfo.java b/java/com/google/gerrit/extensions/common/PluginDefinedInfo.java
index 69bfa2c..e2b1c36 100644
--- a/java/com/google/gerrit/extensions/common/PluginDefinedInfo.java
+++ b/java/com/google/gerrit/extensions/common/PluginDefinedInfo.java
@@ -14,7 +14,24 @@
 
 package com.google.gerrit.extensions.common;
 
+import java.util.Objects;
+
 public class PluginDefinedInfo {
   public String name;
   public String message;
+
+  @Override
+  public boolean equals(Object o) {
+    if (o instanceof PluginDefinedInfo) {
+      PluginDefinedInfo pluginDefinedInfo = (PluginDefinedInfo) o;
+      return Objects.equals(name, pluginDefinedInfo.name)
+          && Objects.equals(message, pluginDefinedInfo.message);
+    }
+    return false;
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(name, message);
+  }
 }
diff --git a/java/com/google/gerrit/extensions/common/PushCertificateInfo.java b/java/com/google/gerrit/extensions/common/PushCertificateInfo.java
index 9eed808..199dbd1 100644
--- a/java/com/google/gerrit/extensions/common/PushCertificateInfo.java
+++ b/java/com/google/gerrit/extensions/common/PushCertificateInfo.java
@@ -14,7 +14,24 @@
 
 package com.google.gerrit.extensions.common;
 
+import java.util.Objects;
+
 public class PushCertificateInfo {
   public String certificate;
   public GpgKeyInfo key;
+
+  @Override
+  public boolean equals(Object o) {
+    if (o instanceof PushCertificateInfo) {
+      PushCertificateInfo pushCertificateInfo = (PushCertificateInfo) o;
+      return Objects.equals(certificate, pushCertificateInfo.certificate)
+          && Objects.equals(key, pushCertificateInfo.key);
+    }
+    return false;
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(certificate, key);
+  }
 }
diff --git a/java/com/google/gerrit/extensions/common/ReviewerUpdateInfo.java b/java/com/google/gerrit/extensions/common/ReviewerUpdateInfo.java
index eccdc64..37e1ceb 100644
--- a/java/com/google/gerrit/extensions/common/ReviewerUpdateInfo.java
+++ b/java/com/google/gerrit/extensions/common/ReviewerUpdateInfo.java
@@ -16,10 +16,28 @@
 
 import com.google.gerrit.extensions.client.ReviewerState;
 import java.sql.Timestamp;
+import java.util.Objects;
 
 public class ReviewerUpdateInfo {
   public Timestamp updated;
   public AccountInfo updatedBy;
   public AccountInfo reviewer;
   public ReviewerState state;
+
+  @Override
+  public boolean equals(Object o) {
+    if (o instanceof ReviewerUpdateInfo) {
+      ReviewerUpdateInfo reviewerUpdateInfo = (ReviewerUpdateInfo) o;
+      return Objects.equals(updated, reviewerUpdateInfo.updated)
+          && Objects.equals(updatedBy, reviewerUpdateInfo.updatedBy)
+          && Objects.equals(reviewer, reviewerUpdateInfo.reviewer)
+          && Objects.equals(state, reviewerUpdateInfo.state);
+    }
+    return false;
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(updated, updatedBy, reviewer, state);
+  }
 }
diff --git a/java/com/google/gerrit/extensions/common/RevisionInfo.java b/java/com/google/gerrit/extensions/common/RevisionInfo.java
index f262901..ea61f31 100644
--- a/java/com/google/gerrit/extensions/common/RevisionInfo.java
+++ b/java/com/google/gerrit/extensions/common/RevisionInfo.java
@@ -17,6 +17,7 @@
 import com.google.gerrit.extensions.client.ChangeKind;
 import java.sql.Timestamp;
 import java.util.Map;
+import java.util.Objects;
 
 public class RevisionInfo {
   // ActionJson#copy(List, RevisionInfo) must be adapted if new fields are added that are not
@@ -34,4 +35,43 @@
   public String commitWithFooters;
   public PushCertificateInfo pushCertificate;
   public String description;
+
+  @Override
+  public boolean equals(Object o) {
+    if (o instanceof RevisionInfo) {
+      RevisionInfo revisionInfo = (RevisionInfo) o;
+      return isCurrent == revisionInfo.isCurrent
+          && Objects.equals(kind, revisionInfo.kind)
+          && _number == revisionInfo._number
+          && Objects.equals(created, revisionInfo.created)
+          && Objects.equals(uploader, revisionInfo.uploader)
+          && Objects.equals(ref, revisionInfo.ref)
+          && Objects.equals(fetch, revisionInfo.fetch)
+          && Objects.equals(commit, revisionInfo.commit)
+          && Objects.equals(files, revisionInfo.files)
+          && Objects.equals(actions, revisionInfo.actions)
+          && Objects.equals(commitWithFooters, revisionInfo.commitWithFooters)
+          && Objects.equals(pushCertificate, revisionInfo.pushCertificate)
+          && Objects.equals(description, revisionInfo.description);
+    }
+    return false;
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(
+        isCurrent,
+        kind,
+        _number,
+        created,
+        uploader,
+        ref,
+        fetch,
+        commit,
+        files,
+        actions,
+        commitWithFooters,
+        pushCertificate,
+        description);
+  }
 }
diff --git a/java/com/google/gerrit/extensions/common/TrackingIdInfo.java b/java/com/google/gerrit/extensions/common/TrackingIdInfo.java
index 0c5ed68..d9b8e22 100644
--- a/java/com/google/gerrit/extensions/common/TrackingIdInfo.java
+++ b/java/com/google/gerrit/extensions/common/TrackingIdInfo.java
@@ -14,6 +14,8 @@
 
 package com.google.gerrit.extensions.common;
 
+import java.util.Objects;
+
 public class TrackingIdInfo {
   public String system;
   public String id;
@@ -22,4 +24,18 @@
     this.system = system;
     this.id = id;
   }
+
+  @Override
+  public boolean equals(Object o) {
+    if (o instanceof TrackingIdInfo) {
+      TrackingIdInfo trackingIdInfo = (TrackingIdInfo) o;
+      return Objects.equals(system, trackingIdInfo.system) && Objects.equals(id, trackingIdInfo.id);
+    }
+    return false;
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(system, id);
+  }
 }
diff --git a/java/com/google/gerrit/extensions/common/VotingRangeInfo.java b/java/com/google/gerrit/extensions/common/VotingRangeInfo.java
index 5c35a49..2f7e9e4 100644
--- a/java/com/google/gerrit/extensions/common/VotingRangeInfo.java
+++ b/java/com/google/gerrit/extensions/common/VotingRangeInfo.java
@@ -14,6 +14,8 @@
 
 package com.google.gerrit.extensions.common;
 
+import java.util.Objects;
+
 public class VotingRangeInfo {
   public int min;
   public int max;
@@ -22,4 +24,18 @@
     this.min = min;
     this.max = max;
   }
+
+  @Override
+  public boolean equals(Object o) {
+    if (o instanceof VotingRangeInfo) {
+      VotingRangeInfo votingRangeInfo = (VotingRangeInfo) o;
+      return min == votingRangeInfo.min && max == votingRangeInfo.max;
+    }
+    return false;
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(min, max);
+  }
 }