diff --git a/java/com/google/gerrit/httpd/raw/CatServlet.java b/java/com/google/gerrit/httpd/raw/CatServlet.java
index 79f3d8bf24..5a3c6ce3c6 100644
--- a/java/com/google/gerrit/httpd/raw/CatServlet.java
+++ b/java/com/google/gerrit/httpd/raw/CatServlet.java
@@ -118,13 +118,13 @@ public class CatServlet extends HttpServlet {
       }
     }
 
-    final Change.Id changeId = patchKey.getParentKey().changeId();
+    final Change.Id changeId = patchKey.patchSetId().changeId();
     String revision;
     try {
       ChangeNotes notes = changeNotesFactory.createChecked(changeId);
       permissionBackend.currentUser().change(notes).check(ChangePermission.READ);
       projectCache.checkedGet(notes.getProjectName()).checkStatePermitsRead();
-      if (patchKey.getParentKey().get() == 0) {
+      if (patchKey.patchSetId().get() == 0) {
         // change edit
         Optional<ChangeEdit> edit = changeEditUtil.byChange(notes);
         if (edit.isPresent()) {
@@ -134,7 +134,7 @@ public class CatServlet extends HttpServlet {
           return;
         }
       } else {
-        PatchSet patchSet = psUtil.get(notes, patchKey.getParentKey());
+        PatchSet patchSet = psUtil.get(notes, patchKey.patchSetId());
         if (patchSet == null) {
           rsp.sendError(HttpServletResponse.SC_NOT_FOUND);
           return;
diff --git a/java/com/google/gerrit/reviewdb/client/Patch.java b/java/com/google/gerrit/reviewdb/client/Patch.java
index 89f30576e1..0f7e4cf8d7 100644
--- a/java/com/google/gerrit/reviewdb/client/Patch.java
+++ b/java/com/google/gerrit/reviewdb/client/Patch.java
@@ -64,10 +64,6 @@ public final class Patch {
     public abstract PatchSet.Id patchSetId();
 
     public abstract String fileName();
-
-    public PatchSet.Id getParentKey() {
-      return patchSetId();
-    }
   }
 
   /** Type of modification made to the file path. */
diff --git a/java/com/google/gerrit/reviewdb/client/PatchLineComment.java b/java/com/google/gerrit/reviewdb/client/PatchLineComment.java
index 6271d19bd4..03359ba155 100644
--- a/java/com/google/gerrit/reviewdb/client/PatchLineComment.java
+++ b/java/com/google/gerrit/reviewdb/client/PatchLineComment.java
@@ -149,7 +149,7 @@ public final class PatchLineComment {
   }
 
   public PatchSet.Id getPatchSetId() {
-    return patchKey.getParentKey();
+    return patchKey.patchSetId();
   }
 
   public int getLine() {
@@ -259,7 +259,7 @@ public final class PatchLineComment {
   public Comment asComment(String serverId) {
     Comment c =
         new Comment(
-            new Comment.Key(uuid, patchKey.fileName(), patchKey.getParentKey().get()),
+            new Comment.Key(uuid, patchKey.fileName(), patchKey.patchSetId().get()),
             author,
             writtenOn,
             side,
diff --git a/java/com/google/gerrit/server/restapi/change/GetDiff.java b/java/com/google/gerrit/server/restapi/change/GetDiff.java
index d832598c12..8b5cdaf757 100644
--- a/java/com/google/gerrit/server/restapi/change/GetDiff.java
+++ b/java/com/google/gerrit/server/restapi/change/GetDiff.java
@@ -140,7 +140,7 @@ public class GetDiff implements RestReadView<FileResource> {
 
     PatchScriptFactory psf;
     PatchSet basePatchSet = null;
-    PatchSet.Id pId = resource.getPatchKey().getParentKey();
+    PatchSet.Id pId = resource.getPatchKey().patchSetId();
     String fileName = resource.getPatchKey().fileName();
     ChangeNotes notes = resource.getRevision().getNotes();
     if (base != null) {
@@ -204,11 +204,11 @@ public class GetDiff implements RestReadView<FileResource> {
       List<DiffWebLinkInfo> links =
           webLinks.getDiffLinks(
               state.getName(),
-              resource.getPatchKey().getParentKey().changeId().get(),
+              resource.getPatchKey().patchSetId().changeId().get(),
               basePatchSet != null ? basePatchSet.getId().get() : null,
               revA,
               MoreObjects.firstNonNull(ps.getOldName(), ps.getNewName()),
-              resource.getPatchKey().getParentKey().get(),
+              resource.getPatchKey().patchSetId().get(),
               revB,
               ps.getNewName());
       result.webLinks = links.isEmpty() ? null : links;
diff --git a/java/com/google/gerrit/server/restapi/change/Reviewed.java b/java/com/google/gerrit/server/restapi/change/Reviewed.java
index 32dcf27483..7152799f61 100644
--- a/java/com/google/gerrit/server/restapi/change/Reviewed.java
+++ b/java/com/google/gerrit/server/restapi/change/Reviewed.java
@@ -40,7 +40,7 @@ public class Reviewed {
           accountPatchReviewStore.call(
               s ->
                   s.markReviewed(
-                      resource.getPatchKey().getParentKey(),
+                      resource.getPatchKey().patchSetId(),
                       resource.getAccountId(),
                       resource.getPatchKey().fileName()));
       return reviewFlagUpdated ? Response.created("") : Response.ok("");
@@ -61,7 +61,7 @@ public class Reviewed {
       accountPatchReviewStore.run(
           s ->
               s.clearReviewed(
-                  resource.getPatchKey().getParentKey(),
+                  resource.getPatchKey().patchSetId(),
                   resource.getAccountId(),
                   resource.getPatchKey().fileName()));
       return Response.none();