private void assertNodeExists(CuratorFramework curator, String path) throws Exception {
    assertNotNull(path);
    assertTrue(curator.checkExists().forPath(path) != null);
  }
See SlotZNode; some tests (and the setup) are c/p-ed or modified from Curator.
llap-client/src/test/org/apache/hadoop/hive/llap/registry/impl/TestSlotZnode.java