@Override
  public void refresh() {
    HiveConf conf = ctx.getConf();
    sleepTime = conf.getTimeVar(
        HiveConf.ConfVars.HIVE_LOCK_SLEEP_BETWEEN_RETRIES, TimeUnit.MILLISECONDS);
    numRetriesForLock = conf.getIntVar(HiveConf.ConfVars.HIVE_LOCK_NUMRETRIES);
    numRetriesForUnLock = conf.getIntVar(HiveConf.ConfVars.HIVE_UNLOCK_NUMRETRIES);
  }
@param ctx  The lock manager context (containing the Hive configuration file)
Start the ZooKeeper client based on the zookeeper cluster specified in the conf.
ql/src/java/org/apache/hadoop/hive/ql/lockmgr/zookeeper/ZooKeeperHiveLockManager.java