netty5服务端与客户端的构建-优快云博客

简单的介绍一些服务端代码的编写顺序。

1.得到 ServerBootstrap的对象，用来监听客户端

ServerBootstrap serverBootstrap = new ServerBootstrap();

2.创建两个线程池

EventLoopGroup boss = new NioEventLoopGroup();
EventLoopGroup worker = new NioEventLoopGroup();

boss用来对端口的监听，worker对数据进行处理

3.设置工厂

serverBootstrap.group(boss, worker);
serverBootstrap.channel(NioServerSocketChannel.class);

4.设置，可以理解为netty3中的管道

serverBootstrap.childHandler(new ChannelInitializer<Channel>() {

				@Override
				protected void initChannel(Channel channel) throws Exception {
					/**
					 * 将“上传下载”数据装饰成String类型
					 */
					channel.pipeline().addLast(new StringDecoder());
					channel.pipeline().addLast(new StringEncoder());
					// 要处理的Handler
					channel.pipeline().addLast(new ServerHandler2());
				}
			});

5.设置TCP参数

serverBootstrap.option(ChannelOption.SO_BACKLOG, 2048);// serverSocketchannel的设置，链接缓冲池的大小
serverBootstrap.childOption(ChannelOption.SO_KEEPALIVE, true);// socketchannel的设置,维持链接的活跃，清除死链接
serverBootstrap.childOption(ChannelOption.TCP_NODELAY, true);// socketchannel的设置,关闭延迟发送

6.绑定端口

ChannelFuture future = serverBootstrap.bind(new InetSocketAddress(
					9090));

7.(等待)关闭客户端

Channel channel = future.channel();
channel.closeFuture().sync();

完整代码如下:

服务端:

package com.netty5.server;

import java.net.InetSocketAddress;

import io.netty.bootstrap.ServerBootstrap;
import io.netty.channel.Channel;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.ChannelOption;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.SimpleChannelInboundHandler;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.nio.NioServerSocketChannel;
import io.netty.handler.codec.string.StringDecoder;
import io.netty.handler.codec.string.StringEncoder;

/**
 * @author Chalmers 2016年2月20日 下午7:52:49
 */
public class NettyServer2 {

	public static void main(String[] args) {
		// 得到ServerBootstrap对象
		ServerBootstrap serverBootstrap = new ServerBootstrap();

		// 创建线程池
		EventLoopGroup boss = new NioEventLoopGroup();
		EventLoopGroup worker = new NioEventLoopGroup();

		try {
			// 类似于Netty3中的工厂
			serverBootstrap.group(boss, worker);
			serverBootstrap.channel(NioServerSocketChannel.class);

			// 类似于Netty3中的管道
			serverBootstrap.childHandler(new ChannelInitializer<Channel>() {

				@Override
				protected void initChannel(Channel channel) throws Exception {
					/**
					 * 将“上传下载”数据装饰成String类型
					 */
					channel.pipeline().addLast(new StringDecoder());
					channel.pipeline().addLast(new StringEncoder());
					// 要处理的Handler
					channel.pipeline().addLast(new ServerHandler2());
				}
			});

			// 设置参数，TCP参数
			serverBootstrap.option(ChannelOption.SO_BACKLOG, 2048);// serverSocketchannel的设置，链接缓冲池的大小
			serverBootstrap.childOption(ChannelOption.SO_KEEPALIVE, true);// socketchannel的设置,维持链接的活跃，清除死链接
			serverBootstrap.childOption(ChannelOption.TCP_NODELAY, true);// socketchannel的设置,关闭延迟发送

			// 绑定端口，并且返回ChannelFuture对象
			ChannelFuture future = serverBootstrap.bind(new InetSocketAddress(
					9090));

			System.out.println("启动服务器...");

			// 等待客户端的关闭
			Channel channel = future.channel();
			// 要记得是closeFuture()，作用是等待服务端的关闭
			channel.closeFuture().sync();
			// 该条语句不会输出，原因:上面没有关闭...
			// System.out.println("客户端已经关闭...");
		} catch (Exception e) {
			e.printStackTrace();
		} finally {
			boss.shutdownGracefully();
			worker.shutdownGracefully();
		}
	}
}

class ServerHandler2 extends SimpleChannelInboundHandler<String> {

	@Override
	protected void messageReceived(ChannelHandlerContext arg0, String arg1)
			throws Exception {
		// 输出接收到的数据
		System.out.println(arg1);

		// 向客户端发送数据
		arg0.channel().writeAndFlush("hi");
	}

	/**
	 * 
	 */
	@Override
	public void channelActive(ChannelHandlerContext ctx) throws Exception {
		super.channelActive(ctx);
		System.out.println("channelActive");
	}

	@Override
	public void channelInactive(ChannelHandlerContext ctx) throws Exception {
		super.channelInactive(ctx);
		System.out.println("channelInactive");
	}
}

客户端:

package com.netty.client;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

import io.netty.bootstrap.Bootstrap;
import io.netty.channel.Channel;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.SimpleChannelInboundHandler;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.nio.NioSocketChannel;
import io.netty.handler.codec.string.StringDecoder;
import io.netty.handler.codec.string.StringEncoder;

/**
 * @author Chalmers 2016年2月20日 下午8:31:25
 */
public class Client {

	public static void main(String[] args) {
		Bootstrap bootstrap = new Bootstrap();

		EventLoopGroup worker = new NioEventLoopGroup();

		bootstrap.channel(NioSocketChannel.class);
		bootstrap.group(worker);

		bootstrap.handler(new ChannelInitializer<Channel>() {

			@Override
			protected void initChannel(Channel channel) throws Exception {
				channel.pipeline().addLast(new StringEncoder());
				channel.pipeline().addLast(new StringDecoder());
				channel.pipeline().addLast(new ClientHandler());
			}
		});

		ChannelFuture future = bootstrap.connect("127.0.0.1", 9090);

		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		while (true) {
			System.out.print("输入: ");
			try {
				String line = br.readLine();
				future.channel().writeAndFlush(line);
			} catch (IOException e) {
				e.printStackTrace();
			}
		}
	}
}

class ClientHandler extends SimpleChannelInboundHandler<String> {

	@Override
	protected void messageReceived(ChannelHandlerContext arg0, String arg1)
			throws Exception {
		System.out.println("收到服务端发送的消息..." + arg1);
	}

	@Override
	public void channelActive(ChannelHandlerContext ctx) throws Exception {
		// TODO Auto-generated method stub
		super.channelActive(ctx);
	}

	@Override
	public void channelInactive(ChannelHandlerContext ctx) throws Exception {
		// TODO Auto-generated method stub
		super.channelInactive(ctx);
	}
	
	
}

因为netty5与netty3的差别挺大，所以注意区分开。

http://moonmonster.iteye.com/blog/2278672

当然，因为本人水平有限，所以更详细的解释可见

netty权威指南作者的博客

http://www.infoq.com/cn/articles/netty-server-create