基于Netty3的RPC架构笔记2之服务端与客户端

   netty版本大致分为  netty3.x  和  netty4.x、netty5.x
   netty可以运用在以下领域？
1分布式进程通信
例如: hadoop、dubbo、akka等具有分布式功能的框架，底层RPC通信都是基于netty实现的，这些框架使用的版本通常都还在用netty3.x
2、游戏服务器开发
最新的游戏服务器有部分公司可能已经开始采用netty4.x 或 netty5.x
1、netty服务端hello world案例
SimpleChannelHandler 处理消息接收和写
{
messageReceived接收消息
channelConnected新连接，通常用来检测IP是否是黑名单
channelDisconnected链接关闭，可以再用户断线的时候清楚用户的缓存数据等
}
2、netty客户端hello world案例
channelDisconnected与channelClosed的区别？
channelDisconnected只有在连接建立后断开才会调用

channelClosed无论连接是否成功都会调用关闭资源

下面是服务端代码

package com.server;import java.net.InetSocketAddress;import java.util.concurrent.ExecutorService;import java.util.concurrent.Executors;import org.jboss.netty.bootstrap.ServerBootstrap;import org.jboss.netty.channel.ChannelPipeline;import org.jboss.netty.channel.ChannelPipelineFactory;import org.jboss.netty.channel.Channels;import org.jboss.netty.channel.socket.nio.NioServerSocketChannelFactory;import org.jboss.netty.handler.codec.string.StringDecoder;import org.jboss.netty.handler.codec.string.StringEncoder;/** * netty服务端入门 */public class Server {public static void main(String[] args) {//服务类ServerBootstrap bootstrap = new ServerBootstrap();//boss线程监听端口，worker线程负责数据读写ExecutorService boss = Executors.newCachedThreadPool();ExecutorService worker = Executors.newCachedThreadPool();//设置niosocket工厂bootstrap.setFactory(new NioServerSocketChannelFactory(boss, worker));//设置管道的工厂bootstrap.setPipelineFactory(new ChannelPipelineFactory() {@Overridepublic ChannelPipeline getPipeline() throws Exception {ChannelPipeline pipeline = Channels.pipeline();pipeline.addLast("decoder", new StringDecoder());pipeline.addLast("encoder", new StringEncoder());pipeline.addLast("helloHandler", new HelloHandler());return pipeline;}});bootstrap.bind(new InetSocketAddress(10101));System.out.println("start!!!");}}

上面是server信息，下面这个是处理绑定信息类

package com.server;import org.jboss.netty.channel.ChannelHandlerContext;import org.jboss.netty.channel.ChannelStateEvent;import org.jboss.netty.channel.ExceptionEvent;import org.jboss.netty.channel.MessageEvent;import org.jboss.netty.channel.SimpleChannelHandler;/** * 消息接受处理类 */public class HelloHandler extends SimpleChannelHandler {/** * 接收消息 */@Overridepublic void messageReceived(ChannelHandlerContext ctx, MessageEvent e) throws Exception {String s = (String) e.getMessage();System.out.println(s);//回写数据ctx.getChannel().write("hi");super.messageReceived(ctx, e);}/** * 捕获异常 */@Overridepublic void exceptionCaught(ChannelHandlerContext ctx, ExceptionEvent e) throws Exception {System.out.println("exceptionCaught");super.exceptionCaught(ctx, e);}/** * 新连接 */@Overridepublic void channelConnected(ChannelHandlerContext ctx, ChannelStateEvent e) throws Exception {System.out.println("channelConnected");super.channelConnected(ctx, e);}/** * 必须是链接已经建立，关闭通道的时候才会触发 */@Overridepublic void channelDisconnected(ChannelHandlerContext ctx, ChannelStateEvent e) throws Exception {System.out.println("channelDisconnected");super.channelDisconnected(ctx, e);}/** * channel关闭的时候触发 */@Overridepublic void channelClosed(ChannelHandlerContext ctx, ChannelStateEvent e) throws Exception {System.out.println("channelClosed");super.channelClosed(ctx, e);}}

接下来是客户端服务代码

package com.client;import java.net.InetSocketAddress;import java.util.Scanner;import java.util.concurrent.ExecutorService;import java.util.concurrent.Executors;import org.jboss.netty.bootstrap.ClientBootstrap;import org.jboss.netty.channel.Channel;import org.jboss.netty.channel.ChannelFuture;import org.jboss.netty.channel.ChannelPipeline;import org.jboss.netty.channel.ChannelPipelineFactory;import org.jboss.netty.channel.Channels;import org.jboss.netty.channel.socket.nio.NioClientSocketChannelFactory;import org.jboss.netty.handler.codec.string.StringDecoder;import org.jboss.netty.handler.codec.string.StringEncoder;/** * netty客户端入门 * */public class Client {public static void main(String[] args) {//服务类ClientBootstrap bootstrap = new  ClientBootstrap();//线程池ExecutorService boss = Executors.newCachedThreadPool();ExecutorService worker = Executors.newCachedThreadPool();//socket工厂bootstrap.setFactory(new NioClientSocketChannelFactory(boss, worker));//管道工厂bootstrap.setPipelineFactory(new ChannelPipelineFactory() {@Overridepublic ChannelPipeline getPipeline() throws Exception {ChannelPipeline pipeline = Channels.pipeline();pipeline.addLast("decoder", new StringDecoder());pipeline.addLast("encoder", new StringEncoder());pipeline.addLast("hiHandler", new HiHandler());return pipeline;}});//连接服务端ChannelFuture connect = bootstrap.connect(new InetSocketAddress("127.0.0.1", 10101));Channel channel = connect.getChannel();System.out.println("client start");Scanner scanner = new Scanner(System.in);while(true){System.out.println("请输入");channel.write(scanner.next());}}}

客户端处理代码

package com.client;import org.jboss.netty.channel.ChannelHandlerContext;import org.jboss.netty.channel.ChannelStateEvent;import org.jboss.netty.channel.ExceptionEvent;import org.jboss.netty.channel.MessageEvent;import org.jboss.netty.channel.SimpleChannelHandler;/** * 消息接受处理类 * @author -琴兽- * */public class HiHandler extends SimpleChannelHandler {/** * 接收消息 */@Overridepublic void messageReceived(ChannelHandlerContext ctx, MessageEvent e) throws Exception {String s = (String) e.getMessage();System.out.println(s);super.messageReceived(ctx, e);}/** * 捕获异常 */@Overridepublic void exceptionCaught(ChannelHandlerContext ctx, ExceptionEvent e) throws Exception {System.out.println("exceptionCaught");super.exceptionCaught(ctx, e);}/** * 新连接 */@Overridepublic void channelConnected(ChannelHandlerContext ctx, ChannelStateEvent e) throws Exception {System.out.println("channelConnected");super.channelConnected(ctx, e);}/** * 必须是链接已经建立，关闭通道的时候才会触发 */@Overridepublic void channelDisconnected(ChannelHandlerContext ctx, ChannelStateEvent e) throws Exception {System.out.println("channelDisconnected");super.channelDisconnected(ctx, e);}/** * channel关闭的时候触发 */@Overridepublic void channelClosed(ChannelHandlerContext ctx, ChannelStateEvent e) throws Exception {System.out.println("channelClosed");super.channelClosed(ctx, e);}}