org.apache.thrift.transport.TTransportException: null

//代码占位符
      } catch (TException tx) {

        // TODO A.this code is not correct

        LOGGER.error("Thrift error occurred during processing of message.", tx);
      } catch (Exception x) {
        // We'll usually receive RuntimeException types here
        // Need to unwrap to ascertain real causing exception before we choose to ignore
        Throwable realCause = x.getCause();
        // Ignore err-logging all transport-level/type exceptions
        if ((realCause != null && realCause instanceof TTransportException)
        
            // TODO B.this code should put in area TODO A，TTransportException is subclass of TException ，TODO A already handled TTransportException, so this code is nessesary . libthrift ver 0.11.0 is collect

            || (x instanceof TTransportException)) {
          if (LOGGER.isDebugEnabled()) {
            // Write to debug, just in case the exception gets required
            LOGGER
                .debug("Received TTransportException during processing of message, ignoring: ", x);
          }
        } else {
          // Log the exception at error level and continue
          LOGGER.error("Error occurred during processing of message.", x);
        }
      }