netty4handler的执行顺序四

接上篇，本例中加有outhandler，先说明，本例是个不正常程序，只能用于理解

1）outhandler要放到inhandler之前，或者至少一个inhandler之前，否者outhadler.write不运行

package com.wang.netty4Out.first;

import org.apache.cassandra.cli.CliParser.newColumnFamily_return;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import io.netty.bootstrap.ServerBootstrap;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.ChannelOption;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.SocketChannel;
import io.netty.channel.socket.nio.NioServerSocketChannel;

/**
* 这个用于测试handler的传递功能
* @author wangzg
*
* 本例子使用的是实现的handler中，各个函数都是先super，然后打印，除了handler1中的channelRead,这样打印出的顺序是，先2后1,也就是最后加进去的，先做，先进去的后做，跟
* 网上的不一致
*
* 本例子中各个handler中的方法，都在最后使用了super()的方法，顺序和网上的一致
*
* 本例子将用于数据解析
* 本例的例子是inhandler2 和inhandler3都发送了数据，但是客户断接收的时候，是连在一起的，因此这里需要想办法，也就是连包拆包
*
* 本例子发现个问题，在Inhandler中都可以使用ctx.writeAndflush(msg),但这样的做法会造成，如果有outhandler的时候，发送回客户端的数据，有多个
* outhandler发回的数据（都是一样的，个数是inhander中ctx.writeAndFlush()个数），如何解决的，既然需要msg向后传递，又不能
* 有多个重复数据发回，那就需要在inhandler的channelRead()不能使用super.channelread(),而是使用ctx.fireChannelRead(加工过的msg)
*/
public class WangNetty4Out1Server {

   private static final Logger LOGGER = LoggerFactory.getLogger(WangNetty4Out1Server.class);

   public void start(int port){
       EventLoopGroup boss = new NioEventLoopGroup();
       EventLoopGroup work = new NioEventLoopGroup();
       ServerBootstrap bootstrap = new ServerBootstrap();
       try {
           bootstrap.group(boss, work)
           .channel(NioServerSocketChannel.class)
           .option(ChannelOption.SO_BACKLOG, 1024)
//           .option(ChannelOption.SO_TIMEOUT, 5 * 1000)
           .childOption(ChannelOption.SO_KEEPALIVE, true)
           .childOption(ChannelOption.SO_RCVBUF, 10 * 1024)
           .childOption(ChannelOption.SO_SNDBUF, 10 * 1024)
           .childHandler(new ChannelInitializer<SocketChannel>() {

               @Override
               protected void initChannel(SocketChannel sc) throws Exception {
                   sc.pipeline().addLast(new WangOuthandler1());

                   sc.pipeline().addLast(new WangInHandler1());
                   sc.pipeline().addLast(new WangInHandler2());
                   sc.pipeline().addLast(new WangInHandler3());

//                   sc.pipeline().addLast(new WangOuthandler1());

               }
           });
           ChannelFuture future = bootstrap.bind(port).sync();
           future.channel().closeFuture().sync();
       } catch (Exception e) {
           LOGGER.error("server 启动失败",e);
       }finally{
           boss.shutdownGracefully();
           work.shutdownGracefully();
       }
   }

   public static void main(String[] args) {
       WangNetty4Out1Server server = new WangNetty4Out1Server();
       server.start(8085);
   }
}

package com.wang.netty4Out.first;

import org.apache.cassandra.utils.OutputHandler.SystemOutput;

import com.wang.netty4.six.NettyUtil;

import io.netty.channel.ChannelHandler;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelInboundHandlerAdapter;

public class WangInHandler1 extends ChannelInboundHandlerAdapter {

   @Override
   public void channelRead(ChannelHandlerContext ctx, Object msg)
           throws Exception {
       // TODO Auto-generated method stub
       System.out.println(" WangInHandler1 channelRead");
       System.out.println(" WangInHandler1 receive:"+NettyUtil.parseByteBufMsg(msg));
       ctx.fireChannelRead(msg);
   }

   @Override
   public void channelReadComplete(ChannelHandlerContext ctx) throws Exception {
       // TODO Auto-generated method stub
       System.out.println(" WangInHandler1 channelReadComplete");
       super.channelReadComplete(ctx);

   }

   @Override
   public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause)
           throws Exception {
       // TODO Auto-generated method stub
       System.out.println(" WangInHandler1 exceptionCaught");
       super.exceptionCaught(ctx, cause);

   }

   @Override
   public void channelActive(ChannelHandlerContext ctx) throws Exception {
       // TODO Auto-generated method stub
       System.out.println(" WangInHandler1 channelActive");
       super.channelActive(ctx);

   }

   @Override
   public void channelInactive(ChannelHandlerContext ctx) throws Exception {
       // TODO Auto-generated method stub
       System.out.println(" WangInHandler1 channelInactive");
       super.channelInactive(ctx);

   }

   @Override
   public void channelRegistered(ChannelHandlerContext ctx) throws Exception {
       // TODO Auto-generated method stub
       System.out.println(" WangInHandler1 channelRegistered");
       super.channelRegistered(ctx);

   }

   @Override
   public void channelUnregistered(ChannelHandlerContext ctx) throws Exception {
       // TODO Auto-generated method stub
       System.out.println(" WangInHandler1 channelUnregistered");
       super.channelUnregistered(ctx);

   }

   @Override
   public void channelWritabilityChanged(ChannelHandlerContext ctx)
           throws Exception {
       // TODO Auto-generated method stub
       System.out.println(" WangInHandler1 channelWritabilityChanged");
       super.channelWritabilityChanged(ctx);

   }

   @Override
   public void userEventTriggered(ChannelHandlerContext ctx, Object evt)
           throws Exception {
       // TODO Auto-generated method stub
       System.out.println(" WangInHandler1 userEventTriggered");
       super.userEventTriggered(ctx, evt);

   }
}

package com.wang.netty4Out.first;

import com.wang.netty4.six.NettyUtil;

import io.netty.channel.ChannelHandler;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelInboundHandlerAdapter;

public class WangInHandler2 extends ChannelInboundHandlerAdapter {

   @Override
   public void channelRead(ChannelHandlerContext ctx, Object msg)
           throws Exception {
       // TODO Auto-generated method stub
       System.out.println(" WangInHandler2 channelRead");
       System.out.println(" WangInHandler2 receive:"+NettyUtil.parseByteBufMsg(msg));
       ctx.writeAndFlush(NettyUtil.packageStringToByteBuf("I am handler2"));
//       ctx.write(NettyUtil.packageStringToByteBuf(" I am inhandler2"));
       super.channelRead(ctx, msg);
//       ctx.fireChannelRead(NettyUtil.packageStringToByteBuf("aaaaaaa"));

   }

   @Override
   public void channelReadComplete(ChannelHandlerContext ctx) throws Exception {
       // TODO Auto-generated method stub
       System.out.println(" WangInHandler2 channelReadComplete");
       super.channelReadComplete(ctx);

   }

   @Override
   public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause)
           throws Exception {
       // TODO Auto-generated method stub
       System.out.println(" WangInHandler2 exceptionCaught");
       super.exceptionCaught(ctx, cause);

   }

   @Override
   public void channelActive(ChannelHandlerContext ctx) throws Exception {
       // TODO Auto-generated method stub
       System.out.println(" WangInHandler2 channelActive");
       super.channelActive(ctx);

   }

   @Override
   public void channelInactive(ChannelHandlerContext ctx) throws Exception {
       // TODO Auto-generated method stub
       System.out.println(" WangInHandler2 channelInactive");
       super.channelInactive(ctx);

   }

   @Override
   public void channelRegistered(ChannelHandlerContext ctx) throws Exception {
       // TODO Auto-generated method stub
       System.out.println(" WangInHandler2 channelRegistered");
       super.channelRegistered(ctx);

   }

   @Override
   public void channelUnregistered(ChannelHandlerContext ctx) throws Exception {
       // TODO Auto-generated method stub
       System.out.println(" WangInHandler2 channelUnregistered");
       super.channelUnregistered(ctx);

   }

   @Override
   public void channelWritabilityChanged(ChannelHandlerContext ctx)
           throws Exception {
       // TODO Auto-generated method stub
       System.out.println(" WangInHandler2 channelWritabilityChanged");
       super.channelWritabilityChanged(ctx);

   }

   @Override
   public void userEventTriggered(ChannelHandlerContext ctx, Object evt)
           throws Exception {
       // TODO Auto-generated method stub
       System.out.println(" WangInHandler2 userEventTriggered");
       super.userEventTriggered(ctx, evt);

   }
}

package com.wang.netty4Out.first;

import com.wang.netty4.six.NettyUtil;

import io.netty.channel.ChannelHandler;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelInboundHandlerAdapter;

public class WangInHandler3 extends ChannelInboundHandlerAdapter {

   @Override
   public void channelRead(ChannelHandlerContext ctx, Object msg)
           throws Exception {
       // TODO Auto-generated method stub
//       super.channelRead(ctx, msg);
       System.out.println(" WangInHandler3 channelRead");
       ctx.writeAndFlush(NettyUtil.packageStringToByteBuf(" I am inHandler3"));
//       ctx.writeAndFlush(msg);
   }

   @Override
   public void channelReadComplete(ChannelHandlerContext ctx) throws Exception {
       // TODO Auto-generated method stub
       System.out.println(" WangInHandler3 channelReadComplete");
       super.channelReadComplete(ctx);

   }

   @Override
   public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause)
           throws Exception {
       // TODO Auto-generated method stub
       System.out.println(" WangInHandler3 exceptionCaught");
       super.exceptionCaught(ctx, cause);

   }

   @Override
   public void channelActive(ChannelHandlerContext ctx) throws Exception {
       // TODO Auto-generated method stub
       System.out.println(" WangInHandler3 channelActive");
       super.channelActive(ctx);

   }

   @Override
   public void channelInactive(ChannelHandlerContext ctx) throws Exception {
       // TODO Auto-generated method stub
       System.out.println(" WangInHandler3 channelInactive");
       super.channelInactive(ctx);

   }

   @Override
   public void channelRegistered(ChannelHandlerContext ctx) throws Exception {
       // TODO Auto-generated method stub
       System.out.println(" WangInHandler3 channelRegistered");
       super.channelRegistered(ctx);

   }

   @Override
   public void channelUnregistered(ChannelHandlerContext ctx) throws Exception {
       // TODO Auto-generated method stub
       System.out.println(" WangInHandler3 channelUnregistered");
       super.channelUnregistered(ctx);

   }

   @Override
   public void channelWritabilityChanged(ChannelHandlerContext ctx)
           throws Exception {
       // TODO Auto-generated method stub
       System.out.println(" WangInHandler3 channelWritabilityChanged");
       super.channelWritabilityChanged(ctx);

   }

   @Override
   public void userEventTriggered(ChannelHandlerContext ctx, Object evt)
           throws Exception {
       // TODO Auto-generated method stub
       System.out.println(" WangInHandler3 userEventTriggered");
       super.userEventTriggered(ctx, evt);
   }
}

运行结果

服务端

WangInHandler1 channelRegistered
WangInHandler2 channelRegistered
WangInHandler3 channelRegistered
WangInHandler1 channelActive
WangInHandler2 channelActive
WangInHandler3 channelActive
WangOuthandler1 read
WangInHandler1 channelRead
WangInHandler1 receive:Are you ok?
WangInHandler2 channelRead
WangInHandler2 receive:
WangOuthandler1 write
WangOuthandler1 receive I am handler2
WangOuthandler1 flush
WangInHandler3 channelRead
WangOuthandler1 write
WangOuthandler1 receive I am inHandler3
WangOuthandler1 flush
WangInHandler1 channelReadComplete
WangInHandler2 channelReadComplete
WangInHandler3 channelReadComplete
WangOuthandler1 read

客户断

channelActive
ctx.channel().localAddress():/192.168.1.31:58072
channelRead

Server said:WangOuthandler1WangOuthandler1

大家可以看到我的客户端接收到了2个WangOuthandler1，原因是Inhandler2和inhandler3都ctx.writeandflush()的原因，同时还有indhandler2的super.channelRead(ctx, msg);

在看服务端，由于我的outhandler放在了inhandler之前，因此WangOuthandler1 read WangInHandler1 channelRead，

同时因为inhandler2的super原因，outhandler1.write第一次接收到了数据，进行写操作，发送给客户端，inhandler3的writeandflush(),再次进入outhandler.write()操作，发送给客户端，因此客户端收到了2个数据WangOuthandler1，因此当inhandler中每一次ctx.write()或这ctx.writeandflush,outhandler1都会发送给客户端，只有使用ctx.firechannelread,不会触发outhandler操作

netty4handler的执行顺序四

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