@Override
  public OpenTxnsResponse open_txns(OpenTxnRequest rqst) throws TException {
    OpenTxnsResponse response = getTxnHandler().openTxns(rqst);
    List<Long> txnIds = response.getTxn_ids();
    boolean isHiveReplTxn = rqst.isSetReplPolicy() && TxnType.DEFAULT.equals(rqst.getTxn_type());
    if (txnIds != null && listeners != null && !listeners.isEmpty() && !isHiveReplTxn) {
      MetaStoreListenerNotifier.notifyEvent(listeners, EventType.OPEN_TXN,
          new OpenTxnEvent(txnIds, this));
    }
    return response;
  }
Check if newRole is in parent hierarchy of curRole
@param newRole
@param curRole
@return true if newRole is curRole or present in its hierarchy
@throws MetaException
standalone-metastore/metastore-server/src/main/java/org/apache/hadoop/hive/metastore/HMSHandler.java