@Override
 public boolean isConnected() {
   if (_zkclient == null) {
     return false;
   }
   ZkConnection zkconnection = (ZkConnection) _zkclient.getConnection();
   if (zkconnection != null) {
     States state = zkconnection.getZookeeperState();
     return state == States.CONNECTED;
   }
   return false;
 }