三、Netty入门到精通(RPC实现)——Netty客户端helloWorld入门

阳光穿透心脏的1/2处 2023-08-17 17:06 114阅读 0赞

### 1、代码 ###

CLient.java

import org.jboss.netty.bootstrap.ClientBootstrap;
    import org.jboss.netty.channel.*;
    import org.jboss.netty.channel.socket.nio.NioClientSocketChannelFactory;
    import org.jboss.netty.handler.codec.string.StringDecoder;
    import org.jboss.netty.handler.codec.string.StringEncoder;
    
    import java.net.InetSocketAddress;
    import java.util.Scanner;
    import java.util.concurrent.ExecutorService;
    import java.util.concurrent.Executors;
    /**
     * \* Created with IntelliJ IDEA.
     * \* User: sunxianpeng
     * \* Date: 2019/9/30
     * \* Time: 11:28
     * \* To change this template use File | Settings | File Templates.
     * \* Description:based on netty 3.10.5.Final
     * \
     */
    public class Client {
        public static void main(String[] args) {
            String host = "openbarrage.douyutv.com"; //"127.0.0.1"
            int port = 8601; //10101
            //1.创建客户端服务类
            //与服务端不同，用的是ClientBootstrap
            ClientBootstrap bootstrap = new ClientBootstrap();
            //2.创建两个线程池
            /**
             * 第一个经常被叫做‘boss’，用来接收进来的连接。
             * 第二个经常被叫做‘worker’，用来处理已经被接收的连接，
             * 一旦‘boss’接收到连接，就会把连接信息注册到‘worker’上。
             * */
            ExecutorService boss = Executors.newCachedThreadPool();
            ExecutorService worker = Executors.newCachedThreadPool();
            //3.为客户端设置一个NioSocket工厂
            //与服务端不同，用的是NioClientSocketChannelFactory
            bootstrap.setFactory(new NioClientSocketChannelFactory(boss, worker));
            //4.设置管道的工厂（匿名内部类实现）
            bootstrap.setPipelineFactory(new ChannelPipelineFactory() {
                //            @Override
                public ChannelPipeline getPipeline() throws Exception {
                    ChannelPipeline pipeline = Channels.pipeline();
                    //设置解码方式为String
                    pipeline.addLast("decoder", new StringDecoder());
                    pipeline.addLast("encoder", new StringEncoder());
                    //设置一个处理服务端消息和各种消息事件的类(Handler)
                    pipeline.addLast("hellohandler", new ClientHelloHandler());
                    return pipeline;
                }
            });
            //5.连接服务端
            ChannelFuture connect = bootstrap.connect(new InetSocketAddress(host, port));
            Channel channel = connect.getChannel();
            //获取控制台输入对象
            Scanner scanner = new Scanner(System.in);
            while (true) {
                //向服务端写入控制台中输入的信息
                System.out.println("请输入：");
                channel.write(scanner.next());
            }
        }
    }

ClientHelloHandler.java

import org.jboss.netty.channel.*;
    //based on netty 3.10.5.Final
    public class ClientHelloHandler extends SimpleChannelHandler {
    	/**
         * 连接关闭
    	 * */
    	@Override
    	public void channelClosed(ChannelHandlerContext ctx, ChannelStateEvent e)
    			throws Exception {
    		System.out.println("channelClosed");
    		super.channelClosed(ctx, e);
    	}
    	/**
    	 * 新建连接
    	 * */
    	@Override
    	public void channelConnected(ChannelHandlerContext ctx, ChannelStateEvent e)
    			throws Exception {
    		System.out.println("channelConnected");
    		super.channelConnected(ctx, e);
    	}
     
    	/**
    	 * 连接断开
    	 * */
    	@Override
    	public void channelDisconnected(ChannelHandlerContext ctx,
    			ChannelStateEvent e) throws Exception {
    		System.out.println("channelDisconnected");
    		super.channelDisconnected(ctx, e);
    	}
    	/**
    	 * 捕获异常
    	 * */
    	@Override
    	public void exceptionCaught(ChannelHandlerContext ctx, ExceptionEvent e)
    			throws Exception {
    		System.out.println("exceptionCaught,error:"+e.toString());
    		super.exceptionCaught(ctx, e);
    	}
    	/**
    	 * 消息接收
    	 * */
    	@Override
    	public void messageReceived(ChannelHandlerContext ctx, MessageEvent e)
    			throws Exception {
    		System.out.println("messageReceived");
    		String msg = (String)e.getMessage();//将字节流转换为String
    		System.out.println(msg);//打印收到的字符串
    		super.messageReceived(ctx, e);
    	}
    }

### 2、测试 ###

先启动服务端，然后启动客户端，

在客户端发送消息，测试是否成功