Netty demo 时间查询

最新推荐文章于 2023-03-11 11:02:53 发布

yunshouhu

最新推荐文章于 2023-03-11 11:02:53 发布

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Netty实现简单的时间查询服务

package com.jiepu.netty2.time;

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;

/**
 * server 有粘包问题
 * 
 * @author xwalker
 */
public class TimeServer {
	public void bind(int port) throws Exception {
		// 服务器线程组 用于网络事件的处理 一个用于服务器接收客户端的连接
		// 另一个线程组用于处理SocketChannel的网络读写
		EventLoopGroup bossGroup = new NioEventLoopGroup();
		EventLoopGroup workerGroup = new NioEventLoopGroup();
		try {
			// NIO服务器端的辅助启动类 降低服务器开发难度
			ServerBootstrap serverBootstrap = new ServerBootstrap();
			serverBootstrap.group(bossGroup, workerGroup)
					.channel(NioServerSocketChannel.class)// 类似NIO中serverSocketChannel
					.option(ChannelOption.SO_BACKLOG, 1024)// 配置TCP参数
					.childHandler(new ChildChannelHandler());// 最后绑定I/O事件的处理类
																// 处理网络IO事件

			// 服务器启动后 绑定监听端口 同步等待成功 主要用于异步操作的通知回调 回调处理用的ChildChannelHandler
			ChannelFuture f = serverBootstrap.bind(port).sync();
			System.out.println("timeServer启动");
			// 等待服务端监听端口关闭
			f.channel().closeFuture().sync();

		} finally {
			// 优雅退出 释放线程池资源
			bossGroup.shutdownGracefully();
			workerGroup.shutdownGracefully();
			System.out.println("服务器优雅的释放了线程资源...");
		}

	}

	/**
	 * 网络事件处理器
	 */
	private class ChildChannelHandler extends ChannelInitializer<SocketChannel> {
		@Override
		protected void initChannel(SocketChannel ch) throws Exception {
			ch.pipeline().addLast(new TimeServerHandler());
		}

	}

	public static void main(String[] args) throws Exception {
		int port = 8000;
		new TimeServer().bind(port);
	}

}

package com.jiepu.netty2.time;


import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelHandlerAdapter;
import io.netty.channel.ChannelHandlerContext;

import java.util.Date;
/**
 * server端网络IO事件处理
 * @author xwalker
 *
 */
public class TimeServerHandler extends ChannelHandlerAdapter {
    @Override
    public void channelRead(ChannelHandlerContext ctx, Object msg)
            throws Exception {
        System.out.println("服务器读取到客户端请求...");
        ByteBuf buf=(ByteBuf) msg;
        byte[] req=new byte[buf.readableBytes()];
        buf.readBytes(req);
        String body=new String(req,"UTF-8");
        System.out.println("the time server receive order:"+body);
        String curentTime="QUERY TIME ORDER".equalsIgnoreCase(body)?new Date(System.currentTimeMillis()).toString():"BAD ORDER";
        ByteBuf resp=Unpooled.copiedBuffer(curentTime.getBytes());
        ctx.write(resp);
        System.out.println("服务器做出了响应");
    }
     
    @Override
    public void channelReadComplete(ChannelHandlerContext ctx) throws Exception {
        ctx.flush();
        System.out.println("服务器readComplete 响应完成");
    }
     
    @Override
    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause)
            throws Exception {
        ctx.close();
        System.out.println("服务器异常退出"+cause.getMessage());
    }
}

package com.jiepu.netty2.time;
 
import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelHandlerAdapter;
import io.netty.channel.ChannelHandlerContext;
 
import java.util.logging.Logger;
/**
 * Client 网络IO事件处理
 * @author xwalker
 *
 */
public class TimeClientHandler extends ChannelHandlerAdapter {
    private static final Logger logger=Logger.getLogger(TimeClientHandler.class.getName());
    private  ByteBuf firstMessage;
    public TimeClientHandler(){
        byte[] req ="QUERY TIME ORDER".getBytes();
        firstMessage=Unpooled.buffer(req.length);
        firstMessage.writeBytes(req);
    }
    @Override
    public void channelActive(ChannelHandlerContext ctx) throws Exception {
        ctx.writeAndFlush(firstMessage);
        System.out.println("客户端active");
    }
     
    @Override
    public void channelRead(ChannelHandlerContext ctx, Object msg)
            throws Exception {
        System.out.println("客户端收到服务器响应数据");
        ByteBuf buf=(ByteBuf) msg;
        byte[] req=new byte[buf.readableBytes()];
        buf.readBytes(req);
        String body=new String(req,"UTF-8");
        System.out.println("Now is:"+body);
         
    }
     
    @Override
    public void channelReadComplete(ChannelHandlerContext ctx) throws Exception {
        ctx.flush();
        System.out.println("客户端收到服务器响应数据处理完成");
    }
     
    @Override
    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause)
            throws Exception {
        logger.warning("Unexpected exception from downstream:"+cause.getMessage());
        ctx.close();
        System.out.println("客户端异常退出");
    }
}

package com.jiepu.netty2.time;

import io.netty.bootstrap.Bootstrap;
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.NioSocketChannel;
/**
 * client 存在TCP粘包问题
 * @author xwlaker
 * Netty实现简单的时间查询服务
 * http://www.oschina.net/code/snippet_374_44686
 *
 */
public class TimeClient {
    /**
     * 连接服务器
     * @param port
     * @param host
     * @throws Exception
     */
    public void connect(int port, String host) throws Exception {
        //配置客户端NIO线程组
        EventLoopGroup group = new NioEventLoopGroup();
        try {
            //客户端辅助启动类 对客户端配置
            Bootstrap b = new Bootstrap();
            b.group(group).channel(NioSocketChannel.class)
                    .option(ChannelOption.TCP_NODELAY, true)
                    .handler(new ChannelInitializer<SocketChannel>() {
                        @Override
                        protected void initChannel(SocketChannel ch)
                                throws Exception {
                            ch.pipeline().addLast(new TimeClientHandler());
                        }
                    });
            //异步链接服务器 同步等待链接成功
            ChannelFuture f = b.connect(host, port).sync();
            //等待链接关闭
            f.channel().closeFuture().sync();
 
        } finally {
            group.shutdownGracefully();
            System.out.println("客户端优雅的释放了线程资源...");
        }
 
    }
 
    public static void main(String[] args) throws Exception {
    	
        new TimeClient().connect(8000, "127.0.0.1");
    }
 
}

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
	<modelVersion>4.0.0</modelVersion>

	<groupId>com.jiepu</groupId>
	<artifactId>netty2</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<packaging>jar</packaging>

	<name>netty2</name>
	<url>http://maven.apache.org</url>

	<properties>
		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
	</properties>

	<dependencies>
		<dependency>
			<groupId>junit</groupId>
			<artifactId>junit</artifactId>
			<version>4.10</version>
			<scope>test</scope>
		</dependency>
		<dependency>
			<groupId>io.netty</groupId>
			<artifactId>netty-all</artifactId><!-- netty-all -->
			<version>5.0.0.Alpha1</version>
		</dependency>
	</dependencies>
	<build>
		<plugins>
			<plugin>
				<groupId>org.apache.maven.plugins</groupId>
				<artifactId>maven-compiler-plugin</artifactId>
				<configuration>
					<source>1.7</source>
					<target>1.7</target>
				</configuration>
			</plugin>

		</plugins>
	</build>
</project>