Add convenience methods for constructing approvals and messages

This saves a lot of boilerplate, nested key construction, ChangeUtil
usage, etc. Particularly in the case of ChangeMessage, we can usually
infer pretty much everything directly from the ChangeContext.

Change-Id: I93eb1e5f5c766b4f661bf21084760141b4d1db02

gerrit-server/src/main/java/com/google/gerrit/server/ApprovalsUtil.java

@@ -26,6 +26,7 @@ import com.google.common.collect.ListMultimap;
 import com.google.common.collect.Lists;
 import com.google.common.collect.Ordering;
 import com.google.common.collect.Sets;
+import com.google.common.primitives.Shorts;
 import com.google.gerrit.common.data.LabelType;
 import com.google.gerrit.common.data.LabelTypes;
 import com.google.gerrit.common.data.Permission;
@@ -86,6 +87,18 @@ public class ApprovalsUtil {
     return SORT_APPROVALS.sortedCopy(approvals);
   }
 
+  public static PatchSetApproval newApproval(PatchSet.Id psId, CurrentUser user,
+      LabelId labelId, int value, Date when) {
+    PatchSetApproval psa = new PatchSetApproval(
+        new PatchSetApproval.Key(
+            psId,
+            user.getAccountId(),
+            labelId),
+        Shorts.checkedCast(value),
+        when);
+    return psa;
+  }
+
   private static Iterable<PatchSetApproval> filterApprovals(
       Iterable<PatchSetApproval> psas, final Account.Id accountId) {
     return Iterables.filter(
@@ -288,12 +301,9 @@ public class ApprovalsUtil {
     Date ts = update.getWhen();
     for (Map.Entry<String, Short> vote : approvals.entrySet()) {
       LabelType lt = labelTypes.byLabel(vote.getKey());
-      cells.add(new PatchSetApproval(new PatchSetApproval.Key(
+      cells.add(
-          ps.getId(),
+          newApproval(ps.getId(), changeCtl.getUser(), lt.getLabelId(),
-          ps.getUploader(),
+              vote.getValue(), ts));
-          lt.getLabelId()),
-          vote.getValue(),
-          ts));
     }
     for (PatchSetApproval psa : cells) {
       update.putApproval(psa.getLabel(), psa.getValue());

gerrit-server/src/main/java/com/google/gerrit/server/ChangeMessagesUtil.java

@@ -14,12 +14,15 @@
 
 package com.google.gerrit.server;
 
+import static com.google.common.base.Preconditions.checkNotNull;
 import static com.google.common.base.Preconditions.checkState;
 
 import com.google.common.annotations.VisibleForTesting;
+import com.google.gerrit.reviewdb.client.Account;
 import com.google.gerrit.reviewdb.client.ChangeMessage;
 import com.google.gerrit.reviewdb.client.PatchSet;
 import com.google.gerrit.reviewdb.server.ReviewDb;
+import com.google.gerrit.server.git.BatchUpdate;
 import com.google.gerrit.server.notedb.ChangeNotes;
 import com.google.gerrit.server.notedb.ChangeUpdate;
 import com.google.gerrit.server.notedb.NotesMigration;
@@ -27,6 +30,7 @@ import com.google.gwtorm.server.OrmException;
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
 
+import java.sql.Timestamp;
 import java.util.Collections;
 import java.util.List;
 import java.util.Objects;
@@ -39,6 +43,25 @@ import java.util.Objects;
  */
 @Singleton
 public class ChangeMessagesUtil {
+  public static ChangeMessage newMessage(BatchUpdate.ChangeContext ctx,
+      String body) throws OrmException {
+    return newMessage(
+        ctx.getDb(), ctx.getChange().currentPatchSetId(),
+        ctx.getUser(), ctx.getWhen(), body);
+  }
+
+  public static ChangeMessage newMessage(
+      ReviewDb db, PatchSet.Id psId, CurrentUser user, Timestamp when,
+      String body) throws OrmException {
+    checkNotNull(psId);
+    Account.Id accountId = user.isInternalUser() ? null : user.getAccountId();
+    ChangeMessage m = new ChangeMessage(
+        new ChangeMessage.Key(psId.getParentKey(), ChangeUtil.messageUUID(db)),
+        accountId, when, psId);
+    m.setMessage(body);
+    return m;
+  }
+
   private static List<ChangeMessage> sortChangeMessages(
       Iterable<ChangeMessage> changeMessage) {
     return ChangeNotes.MESSAGE_BY_TIME.sortedCopy(changeMessage);

gerrit-server/src/main/java/com/google/gerrit/server/change/Abandon.java

@@ -31,7 +31,6 @@ import com.google.gerrit.reviewdb.client.PatchSet;
 import com.google.gerrit.reviewdb.client.Project;
 import com.google.gerrit.reviewdb.server.ReviewDb;
 import com.google.gerrit.server.ChangeMessagesUtil;
-import com.google.gerrit.server.ChangeUtil;
 import com.google.gerrit.server.CurrentUser;
 import com.google.gerrit.server.PatchSetUtil;
 import com.google.gerrit.server.extensions.events.ChangeAbandoned;
@@ -106,7 +105,7 @@ public class Abandon implements RestModifyView<ChangeResource, AbandonInput>,
 
   public Change abandon(ChangeControl control, String msgTxt,
       NotifyHandling notifyHandling) throws RestApiException, UpdateException {
-    Op op = new Op(control.getUser(), msgTxt, notifyHandling);
+    Op op = new Op(msgTxt, notifyHandling);
     try (BatchUpdate u =
         batchUpdateFactory.create(
             dbProvider.get(),
@@ -142,8 +141,7 @@ public class Abandon implements RestModifyView<ChangeResource, AbandonInput>,
                   control.getProject().getNameKey().get(),
                   project.get()));
         }
-        u.addOp(
+        u.addOp(control.getId(), new Op(msgTxt, notifyHandling));
-            control.getId(), new Op(control.getUser(), msgTxt, notifyHandling));
       }
       u.execute();
     }
@@ -164,18 +162,14 @@ public class Abandon implements RestModifyView<ChangeResource, AbandonInput>,
   private class Op extends BatchUpdate.Op {
     private final String msgTxt;
     private final NotifyHandling notifyHandling;
-    private final Account account;
 
     private Change change;
     private PatchSet patchSet;
     private ChangeMessage message;
 
-    private Op(CurrentUser user, String msgTxt, NotifyHandling notifyHandling) {
+    private Op(String msgTxt, NotifyHandling notifyHandling) {
       this.msgTxt = msgTxt;
       this.notifyHandling = notifyHandling;
-      account = user.isIdentifiedUser()
-          ? user.asIdentifiedUser().getAccount()
-          : null;
     }
 
     @Override
@@ -208,19 +202,14 @@ public class Abandon implements RestModifyView<ChangeResource, AbandonInput>,
         msg.append(msgTxt.trim());
       }
 
-      ChangeMessage message = new ChangeMessage(
+      return ChangeMessagesUtil.newMessage(ctx, msg.toString());
-          new ChangeMessage.Key(
-              change.getId(),
-              ChangeUtil.messageUUID(ctx.getDb())),
-          account != null ? account.getId() : null,
-          ctx.getWhen(),
-          change.currentPatchSetId());
-      message.setMessage(msg.toString());
-      return message;
     }
 
     @Override
     public void postUpdate(Context ctx) throws OrmException {
+      Account account = ctx.getUser().isIdentifiedUser()
+          ? ctx.getUser().asIdentifiedUser().getAccount()
+          : null;
       try {
         ReplyToChangeSender cm =
             abandonedSenderFactory.create(ctx.getProject(), change.getId());

gerrit-server/src/main/java/com/google/gerrit/server/change/ChangeInserter.java

@@ -34,7 +34,6 @@ import com.google.gerrit.reviewdb.client.PatchSetInfo;
 import com.google.gerrit.reviewdb.server.ReviewDb;
 import com.google.gerrit.server.ApprovalsUtil;
 import com.google.gerrit.server.ChangeMessagesUtil;
-import com.google.gerrit.server.ChangeUtil;
 import com.google.gerrit.server.IdentifiedUser;
 import com.google.gerrit.server.PatchSetUtil;
 import com.google.gerrit.server.events.CommitReceivedEvent;
@@ -364,11 +363,9 @@ public class ChangeInserter extends BatchUpdate.InsertChangeOp {
     approvalsUtil.addApprovalsForNewPatchSet(
         db, update, labelTypes, patchSet, ctx.getControl(), approvals);
     if (message != null) {
-      changeMessage =
+      changeMessage = ChangeMessagesUtil.newMessage(
-          new ChangeMessage(new ChangeMessage.Key(change.getId(),
+          db, patchSet.getId(), ctx.getUser(), patchSet.getCreatedOn(),
-              ChangeUtil.messageUUID(db)), ctx.getAccountId(),
+          message);
-              patchSet.getCreatedOn(), patchSet.getId());
-      changeMessage.setMessage(message);
       cmUtil.addChangeMessage(db, update, changeMessage);
     }
     return true;

gerrit-server/src/main/java/com/google/gerrit/server/change/CherryPickChange.java

@@ -272,10 +272,6 @@ public class CherryPickChange {
 
     @Override
     public boolean updateChange(ChangeContext ctx) throws OrmException {
-      ChangeMessage changeMessage = new ChangeMessage(
-          new ChangeMessage.Key(
-              ctx.getChange().getId(), ChangeUtil.messageUUID(ctx.getDb())),
-              ctx.getAccountId(), ctx.getWhen(), psId);
       StringBuilder sb = new StringBuilder("Patch Set ")
           .append(psId.get())
           .append(": Cherry Picked")
@@ -284,8 +280,8 @@ public class CherryPickChange {
           .append(destBranch)
           .append(" as commit ")
           .append(cherryPickCommit.name());
-      changeMessage.setMessage(sb.toString());
+      ChangeMessage changeMessage = ChangeMessagesUtil.newMessage(
-
+          ctx.getDb(), psId, ctx.getUser(), ctx.getWhen(), sb.toString());
       cmUtil.addChangeMessage(ctx.getDb(), ctx.getUpdate(psId), changeMessage);
       return true;
     }

gerrit-server/src/main/java/com/google/gerrit/server/change/DeleteAssignee.java

@@ -25,7 +25,6 @@ import com.google.gerrit.reviewdb.client.Change;
 import com.google.gerrit.reviewdb.client.ChangeMessage;
 import com.google.gerrit.reviewdb.server.ReviewDb;
 import com.google.gerrit.server.ChangeMessagesUtil;
-import com.google.gerrit.server.ChangeUtil;
 import com.google.gerrit.server.account.AccountInfoCacheFactory;
 import com.google.gerrit.server.account.AccountJson;
 import com.google.gerrit.server.change.DeleteAssignee.Input;
@@ -115,14 +114,8 @@ public class DeleteAssignee implements RestModifyView<ChangeResource, Input> {
 
     private void addMessage(BatchUpdate.ChangeContext ctx,
         ChangeUpdate update, Account deleted) throws OrmException {
-      ChangeMessage cmsg = new ChangeMessage(
+      ChangeMessage cmsg = ChangeMessagesUtil.newMessage(
-          new ChangeMessage.Key(
+          ctx, "Assignee deleted: " + deleted.getName(anonymousCowardName));
-              ctx.getChange().getId(),
-              ChangeUtil.messageUUID(ctx.getDb())),
-          ctx.getAccountId(), ctx.getWhen(),
-          ctx.getChange().currentPatchSetId());
-      cmsg.setMessage(
-          "Assignee deleted: " + deleted.getName(anonymousCowardName));
       cmUtil.addChangeMessage(ctx.getDb(), update, cmsg);
     }
 

gerrit-server/src/main/java/com/google/gerrit/server/change/DeleteReviewer.java

@@ -36,7 +36,6 @@ import com.google.gerrit.reviewdb.server.ReviewDb;
 import com.google.gerrit.reviewdb.server.ReviewDbUtil;
 import com.google.gerrit.server.ApprovalsUtil;
 import com.google.gerrit.server.ChangeMessagesUtil;
-import com.google.gerrit.server.ChangeUtil;
 import com.google.gerrit.server.IdentifiedUser;
 import com.google.gerrit.server.PatchSetUtil;
 import com.google.gerrit.server.extensions.events.ReviewerDeleted;
@@ -185,11 +184,7 @@ public class DeleteReviewer
       ChangeUpdate update = ctx.getUpdate(currPs.getId());
       update.removeReviewer(reviewerId);
 
-      changeMessage = new ChangeMessage(
+      changeMessage = ChangeMessagesUtil.newMessage(ctx, msg.toString());
-          new ChangeMessage.Key(currChange.getId(),
-              ChangeUtil.messageUUID(ctx.getDb())),
-          ctx.getAccountId(), ctx.getWhen(), currPs.getId());
-      changeMessage.setMessage(msg.toString());
       cmUtil.addChangeMessage(ctx.getDb(), update, changeMessage);
 
       return true;

gerrit-server/src/main/java/com/google/gerrit/server/change/DeleteVote.java

@@ -35,7 +35,6 @@ import com.google.gerrit.reviewdb.client.PatchSetApproval;
 import com.google.gerrit.reviewdb.server.ReviewDb;
 import com.google.gerrit.server.ApprovalsUtil;
 import com.google.gerrit.server.ChangeMessagesUtil;
-import com.google.gerrit.server.ChangeUtil;
 import com.google.gerrit.server.IdentifiedUser;
 import com.google.gerrit.server.PatchSetUtil;
 import com.google.gerrit.server.extensions.events.VoteDeleted;
@@ -170,20 +169,13 @@ public class DeleteVote
       ctx.getDb().patchSetApprovals().upsert(
           Collections.singleton(deletedApproval(ctx)));
 
-      changeMessage =
-          new ChangeMessage(new ChangeMessage.Key(change.getId(),
-              ChangeUtil.messageUUID(ctx.getDb())),
-              ctx.getAccountId(),
-              ctx.getWhen(),
-              change.currentPatchSetId());
       StringBuilder msg = new StringBuilder();
       msg.append("Removed ");
       LabelVote.appendTo(msg, label, checkNotNull(oldApprovals.get(label)));
-      changeMessage.setMessage(
+      msg.append(" by ")
-          msg.append(" by ")
+          .append(userFactory.create(accountId).getNameEmail())
-              .append(userFactory.create(accountId).getNameEmail())
+          .append("\n");
-              .append("\n")
+      changeMessage = ChangeMessagesUtil.newMessage(ctx, msg.toString());
-              .toString());
       cmUtil.addChangeMessage(ctx.getDb(), ctx.getUpdate(psId),
           changeMessage);
 

gerrit-server/src/main/java/com/google/gerrit/server/change/Move.java

@@ -33,8 +33,6 @@ import com.google.gerrit.reviewdb.client.Project;
 import com.google.gerrit.reviewdb.client.RefNames;
 import com.google.gerrit.reviewdb.server.ReviewDb;
 import com.google.gerrit.server.ChangeMessagesUtil;
-import com.google.gerrit.server.ChangeUtil;
-import com.google.gerrit.server.IdentifiedUser;
 import com.google.gerrit.server.PatchSetUtil;
 import com.google.gerrit.server.git.BatchUpdate;
 import com.google.gerrit.server.git.BatchUpdate.ChangeContext;
@@ -94,7 +92,7 @@ public class Move implements RestModifyView<ChangeResource, MoveInput> {
 
     try (BatchUpdate u = batchUpdateFactory.create(dbProvider.get(),
         req.getChange().getProject(), control.getUser(), TimeUtil.nowTs())) {
-      u.addOp(req.getChange().getId(), new Op(control, input));
+      u.addOp(req.getChange().getId(), new Op(input));
       u.execute();
     }
 
@@ -103,14 +101,12 @@ public class Move implements RestModifyView<ChangeResource, MoveInput> {
 
   private class Op extends BatchUpdate.Op {
     private final MoveInput input;
-    private final IdentifiedUser caller;
 
     private Change change;
     private Branch.NameKey newDestKey;
 
-    Op(ChangeControl ctl, MoveInput input) {
+    Op(MoveInput input) {
       this.input = input;
-      this.caller = ctl.getUser().asIdentifiedUser();
     }
 
     @Override
@@ -179,11 +175,8 @@ public class Move implements RestModifyView<ChangeResource, MoveInput> {
         msgBuf.append("\n\n");
         msgBuf.append(input.message);
       }
-      ChangeMessage cmsg = new ChangeMessage(
+      ChangeMessage cmsg =
-          new ChangeMessage.Key(change.getId(),
+          ChangeMessagesUtil.newMessage(ctx, msgBuf.toString());
-              ChangeUtil.messageUUID(ctx.getDb())),
-          caller.getAccountId(), ctx.getWhen(), change.currentPatchSetId());
-      cmsg.setMessage(msgBuf.toString());
       cmUtil.addChangeMessage(ctx.getDb(), update, cmsg);
 
       return true;

gerrit-server/src/main/java/com/google/gerrit/server/change/PatchSetInserter.java

@@ -30,7 +30,6 @@ import com.google.gerrit.reviewdb.server.ReviewDb;
 import com.google.gerrit.server.ApprovalCopier;
 import com.google.gerrit.server.ApprovalsUtil;
 import com.google.gerrit.server.ChangeMessagesUtil;
-import com.google.gerrit.server.ChangeUtil;
 import com.google.gerrit.server.PatchSetUtil;
 import com.google.gerrit.server.ReviewerSet;
 import com.google.gerrit.server.events.CommitReceivedEvent;
@@ -225,9 +224,8 @@ public class PatchSetInserter extends BatchUpdate.Op {
     }
 
     if (message != null) {
-      changeMessage = new ChangeMessage(
+      changeMessage = ChangeMessagesUtil.newMessage(
-          new ChangeMessage.Key(ctl.getId(), ChangeUtil.messageUUID(db)),
+          db, patchSet.getId(), ctx.getUser(), ctx.getWhen(), message);
-          ctx.getAccountId(), ctx.getWhen(), patchSet.getId());
       changeMessage.setMessage(message);
     }
 

gerrit-server/src/main/java/com/google/gerrit/server/change/PostReview.java

@@ -57,6 +57,7 @@ import com.google.gerrit.extensions.restapi.UnprocessableEntityException;
 import com.google.gerrit.extensions.restapi.Url;
 import com.google.gerrit.reviewdb.client.ChangeMessage;
 import com.google.gerrit.reviewdb.client.Comment;
+import com.google.gerrit.reviewdb.client.LabelId;
 import com.google.gerrit.reviewdb.client.Patch;
 import com.google.gerrit.reviewdb.client.PatchLineComment.Status;
 import com.google.gerrit.reviewdb.client.PatchSet;
@@ -790,11 +791,8 @@ public class PostReview implements RestModifyView<RevisionResource, ReviewInput>
           oldApprovals.put(normName, null);
           approvals.put(normName, c.getValue());
         } else if (c == null) {
-          c = new PatchSetApproval(new PatchSetApproval.Key(
+          c = ApprovalsUtil.newApproval(
-                  psId,
+              psId, user, lt.getLabelId(), ent.getValue(), ctx.getWhen());
-                  user.getAccountId(),
-                  lt.getLabelId()),
-              ent.getValue(), ctx.getWhen());
           c.setTag(in.tag);
           c.setGranted(ctx.getWhen());
           ups.add(c);
@@ -832,12 +830,10 @@ public class PostReview implements RestModifyView<RevisionResource, ReviewInput>
         if (del.isEmpty()) {
           // If no existing label is being set to 0, hack in the caller
           // as a reviewer by picking the first server-wide LabelType.
-          PatchSetApproval c = new PatchSetApproval(new PatchSetApproval.Key(
+          LabelId labelId = ctx.getControl().getLabelTypes().getLabelTypes()
-              psId,
+              .get(0).getLabelId();
-              user.getAccountId(),
+          PatchSetApproval c = ApprovalsUtil.newApproval(
-              ctx.getControl().getLabelTypes().getLabelTypes().get(0)
+              psId, user, labelId, 0, ctx.getWhen());
-                  .getLabelId()),
-              (short) 0, ctx.getWhen());
           c.setTag(in.tag);
           c.setGranted(ctx.getWhen());
           ups.add(c);
@@ -896,17 +892,10 @@ public class PostReview implements RestModifyView<RevisionResource, ReviewInput>
         return false;
       }
 
-      message = new ChangeMessage(
+      message = ChangeMessagesUtil.newMessage(
-          new ChangeMessage.Key(
+          ctx.getDb(), psId, user, ctx.getWhen(),
-            psId.getParentKey(), ChangeUtil.messageUUID(ctx.getDb())),
+          "Patch Set " + psId.get() + ":" + buf);
-          user.getAccountId(),
-          ctx.getWhen(),
-          psId);
       message.setTag(in.tag);
-      message.setMessage(String.format(
-          "Patch Set %d:%s",
-          psId.get(),
-          buf.toString()));
       cmUtil.addChangeMessage(ctx.getDb(), ctx.getUpdate(psId), message);
       return true;
     }

gerrit-server/src/main/java/com/google/gerrit/server/change/PublishDraftPatchSet.java

@@ -34,7 +34,7 @@ import com.google.gerrit.reviewdb.client.PatchSet;
 import com.google.gerrit.reviewdb.client.PatchSetInfo;
 import com.google.gerrit.reviewdb.server.ReviewDb;
 import com.google.gerrit.server.ApprovalsUtil;
-import com.google.gerrit.server.ChangeUtil;
+import com.google.gerrit.server.ChangeMessagesUtil;
 import com.google.gerrit.server.CurrentUser;
 import com.google.gerrit.server.PatchSetUtil;
 import com.google.gerrit.server.account.AccountResolver;
@@ -252,15 +252,12 @@ public class PublishDraftPatchSet implements RestModifyView<RevisionResource, In
 
     private void sendReplacePatchSet(Context ctx)
         throws EmailException, OrmException {
-      Account.Id accountId = ctx.getAccountId();
+      ChangeMessage msg = ChangeMessagesUtil.newMessage(
-      ChangeMessage msg =
+          ctx.getDb(), psId, ctx.getUser(), ctx.getWhen(),
-          new ChangeMessage(new ChangeMessage.Key(change.getId(),
+          "Uploaded patch set " + psId.get() + ".");
-              ChangeUtil.messageUUID(ctx.getDb())), accountId,
-              ctx.getWhen(), psId);
-      msg.setMessage("Uploaded patch set " + psId.get() + ".");
       ReplacePatchSetSender cm =
           replacePatchSetFactory.create(ctx.getProject(), change.getId());
-      cm.setFrom(accountId);
+      cm.setFrom(ctx.getAccountId());
       cm.setPatchSet(patchSet, patchSetInfo);
       cm.setChangeMessage(msg.getMessage(), ctx.getWhen());
       cm.addReviewers(recipients.getReviewers());

gerrit-server/src/main/java/com/google/gerrit/server/change/PutTopic.java

@@ -26,7 +26,6 @@ import com.google.gerrit.reviewdb.client.Change;
 import com.google.gerrit.reviewdb.client.ChangeMessage;
 import com.google.gerrit.reviewdb.server.ReviewDb;
 import com.google.gerrit.server.ChangeMessagesUtil;
-import com.google.gerrit.server.ChangeUtil;
 import com.google.gerrit.server.change.PutTopic.Input;
 import com.google.gerrit.server.extensions.events.TopicEdited;
 import com.google.gerrit.server.git.BatchUpdate;
@@ -115,13 +114,7 @@ public class PutTopic implements RestModifyView<ChangeResource, Input>,
       change.setTopic(Strings.emptyToNull(newTopicName));
       update.setTopic(change.getTopic());
 
-      ChangeMessage cmsg = new ChangeMessage(
+      ChangeMessage cmsg = ChangeMessagesUtil.newMessage(ctx, summary);
-          new ChangeMessage.Key(
-              change.getId(),
-              ChangeUtil.messageUUID(ctx.getDb())),
-          ctx.getAccountId(), ctx.getWhen(),
-          change.currentPatchSetId());
-      cmsg.setMessage(summary);
       cmUtil.addChangeMessage(ctx.getDb(), update, cmsg);
       return true;
     }

gerrit-server/src/main/java/com/google/gerrit/server/change/Restore.java

@@ -29,7 +29,6 @@ import com.google.gerrit.reviewdb.client.ChangeMessage;
 import com.google.gerrit.reviewdb.client.PatchSet;
 import com.google.gerrit.reviewdb.server.ReviewDb;
 import com.google.gerrit.server.ChangeMessagesUtil;
-import com.google.gerrit.server.ChangeUtil;
 import com.google.gerrit.server.PatchSetUtil;
 import com.google.gerrit.server.extensions.events.ChangeRestored;
 import com.google.gerrit.server.git.BatchUpdate;
@@ -131,16 +130,7 @@ public class Restore implements RestModifyView<ChangeResource, RestoreInput>,
         msg.append("\n\n");
         msg.append(input.message.trim());
       }
-
+      return ChangeMessagesUtil.newMessage(ctx, msg.toString());
-      ChangeMessage message = new ChangeMessage(
-          new ChangeMessage.Key(
-              change.getId(),
-              ChangeUtil.messageUUID(ctx.getDb())),
-          ctx.getAccountId(),
-          ctx.getWhen(),
-          change.currentPatchSetId());
-      message.setMessage(msg.toString());
-      return message;
     }
 
     @Override

gerrit-server/src/main/java/com/google/gerrit/server/change/Revert.java

@@ -34,7 +34,6 @@ import com.google.gerrit.reviewdb.client.Project;
 import com.google.gerrit.reviewdb.server.ReviewDb;
 import com.google.gerrit.server.ApprovalsUtil;
 import com.google.gerrit.server.ChangeMessagesUtil;
-import com.google.gerrit.server.ChangeUtil;
 import com.google.gerrit.server.CurrentUser;
 import com.google.gerrit.server.GerritPersonIdent;
 import com.google.gerrit.server.PatchSetUtil;
@@ -274,14 +273,8 @@ public class Revert implements RestModifyView<ChangeResource, RevertInput>,
     public boolean updateChange(ChangeContext ctx) throws Exception {
       Change change = ctx.getChange();
       PatchSet.Id patchSetId = change.currentPatchSetId();
-      ChangeMessage changeMessage = new ChangeMessage(
+      ChangeMessage changeMessage = ChangeMessagesUtil.newMessage(ctx,
-          new ChangeMessage.Key(change.getId(),
+          "Created a revert of this change as I" + computedChangeId.name());
-              ChangeUtil.messageUUID(db.get())),
-          ctx.getAccountId(), ctx.getWhen(), patchSetId);
-      StringBuilder msgBuf = new StringBuilder();
-      msgBuf.append("Created a revert of this change as ")
-          .append("I").append(computedChangeId.name());
-      changeMessage.setMessage(msgBuf.toString());
       cmUtil.addChangeMessage(ctx.getDb(), ctx.getUpdate(patchSetId),
           changeMessage);
       return true;

gerrit-server/src/main/java/com/google/gerrit/server/change/SetAssigneeOp.java

@@ -25,7 +25,6 @@ import com.google.gerrit.reviewdb.client.Account;
 import com.google.gerrit.reviewdb.client.Change;
 import com.google.gerrit.reviewdb.client.ChangeMessage;
 import com.google.gerrit.server.ChangeMessagesUtil;
-import com.google.gerrit.server.ChangeUtil;
 import com.google.gerrit.server.IdentifiedUser;
 import com.google.gerrit.server.account.AccountInfoCacheFactory;
 import com.google.gerrit.server.account.AccountsCollection;
@@ -139,13 +138,7 @@ public class SetAssigneeOp extends BatchUpdate.Op {
       msg.append(" to: ");
       msg.append(newAssignee.getName(anonymousCowardName));
     }
-    ChangeMessage cmsg = new ChangeMessage(
+    ChangeMessage cmsg = ChangeMessagesUtil.newMessage(ctx, msg.toString());
-        new ChangeMessage.Key(
-            change.getId(),
-            ChangeUtil.messageUUID(ctx.getDb())),
-        ctx.getAccountId(), ctx.getWhen(),
-        change.currentPatchSetId());
-    cmsg.setMessage(msg.toString());
     cmUtil.addChangeMessage(ctx.getDb(), update, cmsg);
   }
 

gerrit-server/src/main/java/com/google/gerrit/server/change/SetHashtagsOp.java

@@ -28,7 +28,6 @@ import com.google.gerrit.extensions.restapi.BadRequestException;
 import com.google.gerrit.reviewdb.client.Change;
 import com.google.gerrit.reviewdb.client.ChangeMessage;
 import com.google.gerrit.server.ChangeMessagesUtil;
-import com.google.gerrit.server.ChangeUtil;
 import com.google.gerrit.server.extensions.events.HashtagsEdited;
 import com.google.gerrit.server.git.BatchUpdate;
 import com.google.gerrit.server.git.BatchUpdate.ChangeContext;
@@ -129,18 +128,12 @@ public class SetHashtagsOp extends BatchUpdate.Op {
     return true;
   }
 
-  private void addMessage(Context ctx, ChangeUpdate update)
+  private void addMessage(ChangeContext ctx, ChangeUpdate update)
       throws OrmException {
     StringBuilder msg = new StringBuilder();
     appendHashtagMessage(msg, "added", toAdd);
     appendHashtagMessage(msg, "removed", toRemove);
-    ChangeMessage cmsg = new ChangeMessage(
+    ChangeMessage cmsg = ChangeMessagesUtil.newMessage(ctx, msg.toString());
-        new ChangeMessage.Key(
-            change.getId(),
-            ChangeUtil.messageUUID(ctx.getDb())),
-        ctx.getAccountId(), ctx.getWhen(),
-        change.currentPatchSetId());
-    cmsg.setMessage(msg.toString());
     cmUtil.addChangeMessage(ctx.getDb(), update, cmsg);
   }
 

gerrit-server/src/main/java/com/google/gerrit/server/git/MergeOp.java

@@ -47,7 +47,6 @@ import com.google.gerrit.reviewdb.client.PatchSet;
 import com.google.gerrit.reviewdb.client.Project;
 import com.google.gerrit.reviewdb.server.ReviewDb;
 import com.google.gerrit.server.ChangeMessagesUtil;
-import com.google.gerrit.server.ChangeUtil;
 import com.google.gerrit.server.IdentifiedUser;
 import com.google.gerrit.server.InternalUser;
 import com.google.gerrit.server.git.BatchUpdate.ChangeContext;
@@ -764,11 +763,10 @@ public class MergeOp implements AutoCloseable {
 
               change.setStatus(Change.Status.ABANDONED);
 
-              ChangeMessage msg = new ChangeMessage(
+              ChangeMessage msg = ChangeMessagesUtil.newMessage(
-                  new ChangeMessage.Key(change.getId(),
+                  ctx.getDb(), change.currentPatchSetId(),
-                      ChangeUtil.messageUUID(ctx.getDb())),
+                  internalUserFactory.create(), change.getLastUpdatedOn(),
-                  null, change.getLastUpdatedOn(), change.currentPatchSetId());
+                  "Project was deleted.");
-              msg.setMessage("Project was deleted.");
               cmUtil.addChangeMessage(ctx.getDb(),
                   ctx.getUpdate(change.currentPatchSetId()), msg);
 

gerrit-server/src/main/java/com/google/gerrit/server/git/MergedByPushOp.java

@@ -22,8 +22,8 @@ import com.google.gerrit.reviewdb.client.LabelId;
 import com.google.gerrit.reviewdb.client.PatchSet;
 import com.google.gerrit.reviewdb.client.PatchSetApproval;
 import com.google.gerrit.reviewdb.client.PatchSetInfo;
+import com.google.gerrit.server.ApprovalsUtil;
 import com.google.gerrit.server.ChangeMessagesUtil;
-import com.google.gerrit.server.ChangeUtil;
 import com.google.gerrit.server.PatchSetUtil;
 import com.google.gerrit.server.extensions.events.ChangeMerged;
 import com.google.gerrit.server.git.BatchUpdate.ChangeContext;
@@ -149,19 +149,13 @@ public class MergedByPushOp extends BatchUpdate.Op {
       }
     }
     msgBuf.append(".");
-    ChangeMessage msg = new ChangeMessage(
+    ChangeMessage msg = ChangeMessagesUtil.newMessage(
-        new ChangeMessage.Key(change.getId(),
+        ctx.getDb(), psId, ctx.getUser(), ctx.getWhen(), msgBuf.toString());
-            ChangeUtil.messageUUID(ctx.getDb())),
-        ctx.getAccountId(), ctx.getWhen(), psId);
-    msg.setMessage(msgBuf.toString());
     cmUtil.addChangeMessage(ctx.getDb(), update, msg);
 
-    PatchSetApproval submitter = new PatchSetApproval(
+    PatchSetApproval submitter = ApprovalsUtil.newApproval(
-          new PatchSetApproval.Key(
+        change.currentPatchSetId(), ctx.getUser(), LabelId.legacySubmit(),
-              change.currentPatchSetId(),
+        1, ctx.getWhen());
-              ctx.getAccountId(),
-              LabelId.legacySubmit()),
-              (short) 1, ctx.getWhen());
     update.putApproval(submitter.getLabel(), submitter.getValue());
     ctx.getDb().patchSetApprovals().upsert(
         Collections.singleton(submitter));

gerrit-server/src/main/java/com/google/gerrit/server/git/ReplaceOp.java

@@ -34,7 +34,6 @@ import com.google.gerrit.reviewdb.client.PatchSetInfo;
 import com.google.gerrit.server.ApprovalCopier;
 import com.google.gerrit.server.ApprovalsUtil;
 import com.google.gerrit.server.ChangeMessagesUtil;
-import com.google.gerrit.server.ChangeUtil;
 import com.google.gerrit.server.PatchSetUtil;
 import com.google.gerrit.server.account.AccountResolver;
 import com.google.gerrit.server.change.ChangeKindCache;
@@ -279,11 +278,8 @@ public class ReplaceOp extends BatchUpdate.Op {
     if (!Strings.isNullOrEmpty(reviewMessage)) {
       message.append("\n").append(reviewMessage);
     }
-    msg = new ChangeMessage(
+    msg = ChangeMessagesUtil.newMessage(ctx.getDb(), patchSetId, ctx.getUser(),
-        new ChangeMessage.Key(change.getId(),
+        ctx.getWhen(), message.toString());
-            ChangeUtil.messageUUID(ctx.getDb())),
-        ctx.getAccountId(), ctx.getWhen(), patchSetId);
-    msg.setMessage(message.toString());
     cmUtil.addChangeMessage(ctx.getDb(), update, msg);
 
     if (mergedByPushOp == null) {

gerrit-server/src/main/java/com/google/gerrit/server/git/strategy/SubmitStrategyOp.java

@@ -33,7 +33,8 @@ import com.google.gerrit.reviewdb.client.Project;
 import com.google.gerrit.reviewdb.client.RefNames;
 import com.google.gerrit.reviewdb.server.ReviewDb;
 import com.google.gerrit.reviewdb.server.ReviewDbUtil;
-import com.google.gerrit.server.ChangeUtil;
+import com.google.gerrit.server.ApprovalsUtil;
+import com.google.gerrit.server.ChangeMessagesUtil;
 import com.google.gerrit.server.IdentifiedUser;
 import com.google.gerrit.server.git.BatchUpdate;
 import com.google.gerrit.server.git.BatchUpdate.ChangeContext;
@@ -329,15 +330,9 @@ abstract class SubmitStrategyOp extends BatchUpdate.Op {
       byKey.put(psa.getKey(), psa);
     }
 
-    submitter = new PatchSetApproval(
+    submitter = ApprovalsUtil.newApproval(
-          new PatchSetApproval.Key(
+        psId, ctx.getUser(), LabelId.legacySubmit(), 1, ctx.getWhen());
-              psId,
-              ctx.getAccountId(),
-              LabelId.legacySubmit()),
-              (short) 1, ctx.getWhen());
     byKey.put(submitter.getKey(), submitter);
-    submitter.setValue((short) 1);
-    submitter.setGranted(ctx.getWhen());
 
     // Flatten out existing approvals for this patch set based upon the current
     // permissions. Once the change is closed the approvals are not updated at
@@ -415,7 +410,7 @@ abstract class SubmitStrategyOp extends BatchUpdate.Op {
   }
 
   private ChangeMessage message(ChangeContext ctx, CodeReviewCommit commit,
-      CommitMergeStatus s) {
+      CommitMergeStatus s) throws OrmException {
     checkNotNull(s, "CommitMergeStatus may not be null");
     String txt = s.getMessage();
     if (s == CommitMergeStatus.CLEAN_MERGE) {
@@ -452,19 +447,9 @@ abstract class SubmitStrategyOp extends BatchUpdate.Op {
   }
 
   private ChangeMessage message(ChangeContext ctx, PatchSet.Id psId,
-      String body) {
+      String body) throws OrmException {
-    checkNotNull(psId);
+    return ChangeMessagesUtil.newMessage(
-    String uuid;
+        ctx.getDb(), psId, ctx.getUser(), ctx.getWhen(), body);
-    try {
-      uuid = ChangeUtil.messageUUID(ctx.getDb());
-    } catch (OrmException e) {
-      return null;
-    }
-    ChangeMessage m = new ChangeMessage(
-        new ChangeMessage.Key(psId.getParentKey(), uuid),
-        ctx.getAccountId(), ctx.getWhen(), psId);
-    m.setMessage(body);
-    return m;
   }
 
   private void setMerged(ChangeContext ctx, ChangeMessage msg)