@Override
  public void process(String host, String value, ApplicationId applicationId,
      ApplicationSubmissionContext submissionContext) {
    Set<String> applicationTags = submissionContext.getApplicationTags();
    if (applicationTags == null) {
      applicationTags = new HashSet<>();
    } else {
      applicationTags = new HashSet<>(applicationTags);
    }
    applicationTags.add(value);
    submissionContext.setApplicationTags(applicationTags);
  }
@Test
  public void testTagAddProcessor() {
    ContextProcessor tagAddProcessor = new TagAddProcessor();
    ApplicationId app = ApplicationId.newInstance(123456, 111);
    ApplicationSubmissionContext applicationSubmissionContext =
        mock(ApplicationSubmissionContext.class);
    when(applicationSubmissionContext.getApplicationId()).thenReturn(app);
    tagAddProcessor.process("host.cluster2.com",
        "cluster:cluster1", app, applicationSubmissionContext);
    Set<String> applicationTags = new HashSet<String>();
    applicationTags.add("cluster:cluster1");
    verify(applicationSubmissionContext, times(1))
        .setApplicationTags(applicationTags);
  }