public static NotFoundException namespaceNotFound(String appId, String clusterName, String namespaceName) {
    return new NotFoundException("namespace not found for appId:%s clusterName:%s namespaceName:%s", appId, clusterName, namespaceName);
  }
@Test
  public void testNamespaceNotFoundException() {
    NotFoundException exception = NotFoundException.namespaceNotFound(appId, clusterName, namespaceName);
    assertEquals(exception.getMessage(), "namespace not found for appId:app-1001 clusterName:test namespaceName:application");

    exception = NotFoundException.namespaceNotFound(66);
    assertEquals(exception.getMessage(), "namespace not found for namespaceId:66");
  }