diff --git a/java/com/google/gerrit/server/change/GetRelatedChangesUtil.java b/java/com/google/gerrit/server/change/GetRelatedChangesUtil.java
index 27eeae1..9a75469 100644
--- a/java/com/google/gerrit/server/change/GetRelatedChangesUtil.java
+++ b/java/com/google/gerrit/server/change/GetRelatedChangesUtil.java
@@ -91,8 +91,7 @@
   }
 
   private List<ChangeData> getUnsortedRelated(
-      ChangeData changeData, PatchSet basePs, boolean alwaysIncludeOriginalChange)
-      throws IOException, PermissionBackendException {
+      ChangeData changeData, PatchSet basePs, boolean alwaysIncludeOriginalChange) {
     Set<String> groups = getAllGroups(changeData.patchSets());
     logger.atFine().log("groups = %s", groups);
     if (groups.isEmpty()) {
diff --git a/java/com/google/gerrit/server/index/change/ChangeField.java b/java/com/google/gerrit/server/index/change/ChangeField.java
index 3585d13..1c89566f 100644
--- a/java/com/google/gerrit/server/index/change/ChangeField.java
+++ b/java/com/google/gerrit/server/index/change/ChangeField.java
@@ -988,7 +988,7 @@
 
   /** Serialized change object, used for pre-populating results. */
   private static final TypeToken<Entities.Change> CHANGE_TYPE_TOKEN =
-      new TypeToken<Entities.Change>() {
+      new TypeToken<>() {
         private static final long serialVersionUID = 1L;
       };
 
@@ -1007,7 +1007,7 @@
 
   /** Serialized approvals for the current patch set, used for pre-populating results. */
   private static final TypeToken<Iterable<Entities.PatchSetApproval>> APPROVAL_TYPE_TOKEN =
-      new TypeToken<Iterable<Entities.PatchSetApproval>>() {
+      new TypeToken<>() {
         private static final long serialVersionUID = 1L;
       };
 
@@ -1300,7 +1300,7 @@
 
   /** Serialized patch set object, used for pre-populating results. */
   private static final TypeToken<Iterable<Entities.PatchSet>> PATCH_SET_TYPE_TOKEN =
-      new TypeToken<Iterable<Entities.PatchSet>>() {
+      new TypeToken<>() {
         private static final long serialVersionUID = 1L;
       };
 
@@ -1621,7 +1621,7 @@
   /** Serialized submit requirements, used for pre-populating results. */
   private static final TypeToken<Iterable<Cache.SubmitRequirementResultProto>>
       STORED_SUBMIT_REQUIREMENTS_TYPE_TOKEN =
-          new TypeToken<Iterable<Cache.SubmitRequirementResultProto>>() {
+          new TypeToken<>() {
             private static final long serialVersionUID = 1L;
           };
 
diff --git a/java/com/google/gerrit/server/patch/gitfilediff/GitFileDiffCacheImpl.java b/java/com/google/gerrit/server/patch/gitfilediff/GitFileDiffCacheImpl.java
index 2b856fb..43a212c 100644
--- a/java/com/google/gerrit/server/patch/gitfilediff/GitFileDiffCacheImpl.java
+++ b/java/com/google/gerrit/server/patch/gitfilediff/GitFileDiffCacheImpl.java
@@ -28,6 +28,7 @@
 import com.google.common.collect.MultimapBuilder;
 import com.google.common.collect.Multimaps;
 import com.google.common.collect.Streams;
+import com.google.common.flogger.FluentLogger;
 import com.google.gerrit.entities.Patch;
 import com.google.gerrit.entities.Project;
 import com.google.gerrit.extensions.client.DiffPreferencesInfo.Whitespace;
@@ -66,6 +67,7 @@
 import org.eclipse.jgit.diff.DiffFormatter;
 import org.eclipse.jgit.diff.HistogramDiff;
 import org.eclipse.jgit.diff.RawTextComparator;
+import org.eclipse.jgit.errors.MissingObjectException;
 import org.eclipse.jgit.lib.AbbreviatedObjectId;
 import org.eclipse.jgit.lib.Config;
 import org.eclipse.jgit.lib.ObjectId;
@@ -76,6 +78,7 @@
 /** Implementation of the {@link GitFileDiffCache} */
 @Singleton
 public class GitFileDiffCacheImpl implements GitFileDiffCache {
+  private static final FluentLogger logger = FluentLogger.forEnclosingClass();
   private static final String GIT_DIFF = "git_file_diff";
 
   public static Module module() {
@@ -340,8 +343,7 @@
         throws IOException {
       if (!key.useTimeout()) {
         try (CloseablePool<DiffFormatter>.Handle formatter = diffPool.get()) {
-          FileHeader fileHeader = formatter.get().toFileHeader(diffEntry);
-          return GitFileDiff.create(diffEntry, fileHeader);
+          return GitFileDiff.create(diffEntry, getFileHeader(formatter, diffEntry));
         }
       }
       // This submits the DiffFormatter to a different thread. The CloseablePool and our usage of it
@@ -353,7 +355,7 @@
           diffExecutor.submit(
               () -> {
                 try (CloseablePool<DiffFormatter>.Handle formatter = diffPool.get()) {
-                  return GitFileDiff.create(diffEntry, formatter.get().toFileHeader(diffEntry));
+                  return GitFileDiff.create(diffEntry, getFileHeader(formatter, diffEntry));
                 }
               });
       try {
@@ -385,6 +387,46 @@
           ? diffEntry.getOldPath()
           : diffEntry.getNewPath();
     }
+
+    private FileHeader getFileHeader(
+        CloseablePool<DiffFormatter>.Handle formatter, DiffEntry diffEntry) throws IOException {
+      logger.atFine().log("getting file header for %s", formatDiffEntryForLogging(diffEntry));
+      try {
+        return formatter.get().toFileHeader(diffEntry);
+      } catch (MissingObjectException e) {
+        throw new IOException(
+            String.format("Failed to get file header for %s", formatDiffEntryForLogging(diffEntry)),
+            e);
+      }
+    }
+
+    private String formatDiffEntryForLogging(DiffEntry diffEntry) {
+      StringBuilder buf = new StringBuilder();
+      buf.append("DiffEntry[");
+      buf.append(diffEntry.getChangeType());
+      buf.append(" ");
+      switch (diffEntry.getChangeType()) {
+        case ADD:
+          buf.append(String.format("%s (%s)", diffEntry.getNewPath(), diffEntry.getNewId().name()));
+          break;
+        case COPY:
+        case RENAME:
+          buf.append(
+              String.format(
+                  "%s (%s) -> %s (%s)",
+                  diffEntry.getOldPath(),
+                  diffEntry.getOldId().name(),
+                  diffEntry.getNewPath(),
+                  diffEntry.getNewId().name()));
+          break;
+        case DELETE:
+        case MODIFY:
+          buf.append(String.format("%s (%s)", diffEntry.getOldPath(), diffEntry.getOldId().name()));
+          break;
+      }
+      buf.append("]");
+      return buf.toString();
+    }
   }
 
   /**
diff --git a/java/com/google/gerrit/server/query/change/ChangeData.java b/java/com/google/gerrit/server/query/change/ChangeData.java
index 78615bf..fc4df49 100644
--- a/java/com/google/gerrit/server/query/change/ChangeData.java
+++ b/java/com/google/gerrit/server/query/change/ChangeData.java
@@ -966,7 +966,7 @@
    * submit requirements are evaluated online.
    *
    * <p>For changes loaded from the index, the value will be set from index field {@link
-   * com.google.gerrit.server.index.change.ChangeField#STORED_SUBMIT_REQUIREMENTS}.
+   * com.google.gerrit.server.index.change.ChangeField#STORED_SUBMIT_REQUIREMENTS_FIELD}.
    */
   public Map<SubmitRequirement, SubmitRequirementResult> submitRequirements() {
     if (submitRequirements == null) {
diff --git a/javatests/com/google/gerrit/acceptance/api/change/RebaseIT.java b/javatests/com/google/gerrit/acceptance/api/change/RebaseIT.java
index 4248ac5..74bd94e 100644
--- a/javatests/com/google/gerrit/acceptance/api/change/RebaseIT.java
+++ b/javatests/com/google/gerrit/acceptance/api/change/RebaseIT.java
@@ -844,9 +844,11 @@
     public void setUp() throws Exception {
       init(
           id -> {
+            @SuppressWarnings("unused")
             Object unused = gApi.changes().id(id).rebaseChain();
           },
           (id, in) -> {
+            @SuppressWarnings("unused")
             Object unused = gApi.changes().id(id).rebaseChain(in);
           });
     }
diff --git a/javatests/com/google/gerrit/server/index/account/AccountFieldTest.java b/javatests/com/google/gerrit/server/index/account/AccountFieldTest.java
index 65eb3b8..a40afe8 100644
--- a/javatests/com/google/gerrit/server/index/account/AccountFieldTest.java
+++ b/javatests/com/google/gerrit/server/index/account/AccountFieldTest.java
@@ -40,8 +40,7 @@
     String metaId = "0e39795bb25dc914118224995c53c5c36923a461";
     account.setMetaId(metaId);
     Iterable<byte[]> refStates =
-        (Iterable<byte[]>)
-            AccountField.REF_STATE_SPEC.get(AccountState.forAccount(account.build()));
+        AccountField.REF_STATE_SPEC.get(AccountState.forAccount(account.build()));
     List<String> values = toStrings(refStates);
     String expectedValue =
         allUsersName.get() + ":" + RefNames.refsUsers(account.id()) + ":" + metaId;