private static final int SESSION_TIMEOUT = 10000;
private static final String CONNECTION_STRING = "127.0.0.1:2181";
private static final String ZK_PATH = "/leader";
private ZooKeeper zk = null;

private CountDownLatch connectedSemaphore = new CountDownLatch(1);

/**
 * 创建ZK连接
 *
 * @param connectString  ZK服务器地址列表
 * @param sessionTimeout Session超时时间
 */
public void createConnection(String connectString, int sessionTimeout) {
    this.releaseConnection();
    try {
        // this代表有监听
        zk = new ZooKeeper(connectString, sessionTimeout, this);
        connectedSemaphore.await();
    } catch (InterruptedException e) {
        System.out.println("连接创建失败，发生 InterruptedException");
        e.printStackTrace();
    } catch (IOException e) {
        System.out.println("连接创建失败，发生 IOException");
        e.printStackTrace();
    }
}

public static  void register(String address,int port) {
        try {
            ZooKeeper zooKeeper = new ZooKeeper("localhost:2181",5000,(watchedEvent)->{});
            logger.warn("连接zk");
            Stat exists = zooKeeper.exists(BASE_SERVICES + SERVICE_NAME, false);
            logger.warn("判断是否存在" + exists);
            if(exists==null) {
                logger.warn("创建路径" );
                zooKeeper.create(BASE_SERVICES,"".getBytes(), ZooDefs.Ids.OPEN_ACL_UNSAFE,CreateMode.PERSISTENT);
                zooKeeper.create(BASE_SERVICES + SERVICE_NAME,"".getBytes(), ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);

            }
            String server_path = address+":"+port;
            logger.warn("server_path:" + server_path);
            zooKeeper.create(BASE_SERVICES + SERVICE_NAME+"/child",server_path.getBytes(), ZooDefs.Ids.OPEN_ACL_UNSAFE,CreateMode.EPHEMERAL_SEQUENTIAL);
            logger.warn("保存成功" );
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

private void updateServiceList() {
       try{

           logger.warn("ip 改变 开始更新ip地址");
           List<String> children = zooKeeper.getChildren(BASE_SERVICES  + SERVICE_NAME, true);
           List<String> newServerList = new ArrayList<String>();
           for(String subNode:children) {
               byte[] data = zooKeeper.getData(BASE_SERVICES  + SERVICE_NAME + "/" + subNode, false, null);
               String host = new String(data, "utf-8");
               System.out.println("host:"+host);
               newServerList.add(host);
           }
           LoadBalance.SERVICE_LIST = newServerList;
       }catch (Exception e) {
           e.printStackTrace();
       }
    }