code: @Override
      public void messageReceived(IoSession session, Object message) throws Exception {
          if (log.isTraceEnabled()) {
              log.trace("Message received (session: {}) {}", session.getId(), message);
          }
          if (message instanceof WSMessage) {
              WebSocketConnection conn = (WebSocketConnection) session.getAttribute(Constants.CONNECTION);
              if (conn != null) {
                  conn.receive((WSMessage) message);
              }
          } else {
              log.trace("Non-WSMessage received {}", message);
          }
      }
docs: {@inheritDoc}