docs: @Handler(channels = NetworkChannel.class)
      public void onInput(Input<ByteBuffer> event, TcpChannel netConnChannel)
              throws InterruptedException, ProtocolException {
          Optional<WebAppMsgChannel> appChannel
              = netConnChannel.associated(WebAppMsgChannel.class);
          if (appChannel.isPresent()) {
              appChannel.get().handleNetInput(event, netConnChannel);
          }
      }