Dubbo请求数据的发送过程

调用过程（IMAF FLADR HHAANN） （3invoke + doInvoke）*2+3request+3send+write

Proxy0#sayHello(String)

​ ->InvokerInvocationHandle#invoke

​ ->MockClusterInvoker#invoke

​ ->AbstractClusterInvoker#invoke

​ ->FailoverClusterInvoker#doInvoke

​ ->Filter#invoke

​ ->ListenerInvokerWrapper#invoke

​ ->AbstractInvoker#invoke

​ ->DubboInvoker#doInvoke

​ ->ReferenceCountExchangeClient#request

​ ->HeadExchangeClient#request

​ ->HeadExchangeChannel#request

​ ->AbstractPeer#send

​ ->AbstractClient#send

​ ->NettyChannel#send

​ ->NioClientSocketChannel#write

调用服务(NAMHAE) messageReceved+receved*4+execute

NettyHandler#messageReceived(ChannelHandlerContext, MessageEvent)

​ —> AbstractPeer#received(Channel, Object)

​ —> MultiMessageHandler#received(Channel, Object)

​ —> HeartbeatHandler#received(Channel, Object)

​ —> AllChannelHandler#received(Channel, Object)

​ —> ExecutorService#execute(Runnable) // 由线程池执行后续的调用逻辑