Make clusterStatePublished method final in ClusterStateUpdateTask

Author: ywelsch

server/src/main/java/org/elasticsearch/cluster/ClusterStateUpdateTask.java

@@ -62,6 +62,12 @@ public String describeTasks(List<ClusterStateUpdateTask> tasks) {
      */
     public abstract void onFailure(String source, Exception e);
 
+    @Override
+    public final void clusterStatePublished(ClusterChangedEvent clusterChangedEvent) {
+        // final, empty implementation here as this method should only be defined in combination
+        // with a batching executor as it will always be executed within the system context.
+    }
+
     /**
      * If the cluster state update task wasn't processed by the provided timeout, call
      * {@link ClusterStateTaskListener#onFailure(String, Exception)}. May return null to indicate no timeout is needed (default).

server/src/test/java/org/elasticsearch/cluster/service/MasterServiceTests.java

@@ -209,13 +209,6 @@ public void clusterStateProcessed(String source, ClusterState oldState, ClusterS
                     latch.countDown();
                 }
 
-                @Override
-                public void clusterStatePublished(ClusterChangedEvent clusterChangedEvent) {
-                    assertTrue(threadPool.getThreadContext().isSystemContext());
-                    assertEquals(Collections.emptyMap(), threadPool.getThreadContext().getHeaders());
-                    latch.countDown();
-                }
-
                 @Override
                 protected Void newResponse(boolean acknowledged) {
                     return null;

x-pack/plugin/ml/src/test/java/org/elasticsearch/xpack/ml/integration/DeleteJobIT.java

@@ -47,7 +47,7 @@ public void onFailure(String source, Exception e) {
             }
 
             @Override
-            public void clusterStatePublished(ClusterChangedEvent clusterChangedEvent) {
+            public void clusterStateProcessed(String source, ClusterState oldState, ClusterState newState) {
                 markAsDeletedLatch.countDown();
             }
         });
@@ -90,7 +90,7 @@ public void onFailure(String source, Exception e) {
             }
 
             @Override
-            public void clusterStatePublished(ClusterChangedEvent clusterChangedEvent) {
+            public void clusterStateProcessed(String source, ClusterState oldState, ClusterState newState) {
                 removeJobLatch.countDown();
             }
         });