@Override
    public void close() {
        if (Objects.nonNull(zkClient)) {
            zkClient.close();
        }
    }
Instantiates a new Zookeeper cache manager.

@param shenyuConfig         the shenyu config
@param zkClient             the zk client
@param pluginDataSubscriber the plugin data subscriber
@param metaDataSubscribers  the meta data subscribers
@param authDataSubscribers  the auth data subscribers
@param proxySelectorDataSubscribers the proxy selector data subscribers
@param discoveryUpstreamDataSubscribers the discovery upstream data subscribers
shenyu-sync-data-center/shenyu-sync-data-zookeeper/src/main/java/org/apache/shenyu/sync/data/zookeeper/ZookeeperSyncDataService.java