_gZkClient = new ZkClient(ZK_ADDR);
_gZkClient.setZkSerializer(new ZNRecordSerializer());
_gSetupTool = new ClusterSetup(ZK_ADDR);
// start admin
_adminThread = new AdminThread(ZK_ADDR, ADMIN_PORT);
_adminThread.start();
// create a client
_gClient = new Client(Protocol.HTTP);