@Test
  public void testJobModelVersionChangeWithChangeInWorkAssignment() throws Exception {
    BiConsumer<ZkBarrierForVersionUpgrade, JobCoordinatorListener> verificationMethod =
      (barrier, listener) -> {
        verify(listener, times(1)).onJobModelExpired();
        verify(barrier, times(1)).join(TEST_JOB_MODEL_VERSION, PROCESSOR_ID);
      };
    testJobModelVersionChangeHelper(null, mock(JobModel.class), verificationMethod);
  }
Test job model version changed changes to work assignment. In this scenario, existing work should
be stopped a.k.a processor should stop the container through the listener. The processor then proceeds to join
the barrier to notify its acceptance on the proposed job model.
samza-core/src/test/java/org/apache/samza/zk/TestZkJobCoordinator.java