code: @Override
      public void messageReceived(IoSession session, Object message)
              throws Exception {
          MessageHandler<Object> handler = findReceivedMessageHandler(message.getClass());
          if (handler != null) {
              handler.handleMessage(session, message);
          } else {
              throw new UnknownMessageTypeException(
                      "No message handler found for message type: " +
                      message.getClass().getSimpleName());
          }
      }
docs: Forwards the received events into the appropriate {@link MessageHandler}
  which is registered by {@link #addReceivedMessageHandler(Class, MessageHandler)}.
  
  <b>Warning !</b> If you are to overload this method, be aware that you
  _must_ call the messageHandler in your own method, otherwise it won't
  be called.