code: private void lockDataLine(String groupId, String unitId, Set<String> lockIdSet, boolean isXLock) throws TxcLogicException {
          try {
              if (!reliableMessenger.acquireLocks(groupId, lockIdSet, isXLock ? DTXLocks.X_LOCK : DTXLocks.S_LOCK)) {
                  throw new TxcLogicException("resource is locked! place try again later.");
              }
              globalContext.addTxcLockId(groupId, unitId, lockIdSet);
          } catch (RpcException e) {
              throw new TxcLogicException("can't contact to any TM for lock info. default error.");
          }
      }
docs: lock data line
  
  @param groupId   groupId
  @param unitId    unitId
  @param lockIdSet lockIdSet
  @param isXLock   isXLock
  @throws TxcLogicException 业务异常