@Bean
    @ConditionalOnMissingBean(ZookeeperDataChangedListener.class)
    public DataChangedListener zookeeperDataChangedListener(final ZookeeperClient zkClient) {
        return new ZookeeperDataChangedListener(zkClient);
    }
@Test
    public void testZookeeperDataChangedListener() {
        ZookeeperSyncConfiguration zookeeperListener = new ZookeeperSyncConfiguration();
        assertNotNull(zookeeperListener.zookeeperDataChangedListener(zkClient));
    }