netty4.0 Server和Client的通信-白红宇

创建一个maven项目

添加Netty依赖

<groupId>io.netty</groupId>

<artifactId>netty-all</artifactId>

<version>4.1.16.Final</version>

</dependency>

Server端开发

public class HelloServer {

public void start(int port) {

ServerBootstrap serverBootstrap = new ServerBootstrap();//注意和 client 的区别

EventLoopGroup boosGroup = new NioEventLoopGroup();

EventLoopGroup workerGroup = new NioEventLoopGroup();

serverBootstrap.group(boosGroup, workerGroup);

serverBootstrap.channel(NioServerSocketChannel.class);//注意和 client 端的区别，client 端是 NioSocketChannel

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

protected void initChannel(SocketChannel socketChannel) throws Exception {

ChannelPipeline pipeline = socketChannel.pipeline();

pipeline.addLast(new HelloServerInHandler());

}

});

serverBootstrap.option(ChannelOption.SO_BACKLOG, 128);

serverBootstrap.childOption(ChannelOption.SO_KEEPALIVE, true);

try {

// 绑定端口，开始接收进来的连接

ChannelFuture f = serverBootstrap.bind(port).sync();

// 等待服务器 socket 关闭。

// 在这个例子中，这不会发生，但你可以优雅地关闭你的服务器。

f.channel().closeFuture().sync();

} catch (InterruptedException e) {

e.printStackTrace();

} finally {

boosGroup.shutdownGracefully();

workerGroup.shutdownGracefully();

}

public static void main(String[] args) {

HelloServer helloServer = new HelloServer();

int port = 8080;

if (args.length > 0) {

port = Integer.parseInt(args[0]);

}

helloServer.start(port);

}

server 消息处理

@ChannelHandler.Sharable

public class HelloServerInHandler extends ChannelInboundHandlerAdapter {

@Override

public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {

try{

ByteBuf inMsg = (ByteBuf) msg;

byte[] bytes = new byte[inMsg.readableBytes()];

inMsg.readBytes(bytes);

String inStr = new String(bytes);

System.out.println("client send msg: " + inStr);

String response = "i am ok!";

ByteBuf outMsg = ctx.alloc().buffer(4 * response.length());

outMsg.writeBytes(response.getBytes());

ctx.writeAndFlush(outMsg);

}finally {

ReferenceCountUtil.release(msg);

}

@Override

public void channelReadComplete(ChannelHandlerContext ctx) throws Exception {

super.channelReadComplete(ctx);

ctx.flush();

}

@Override

public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {

super.exceptionCaught(ctx, cause);

ctx.close();

}

client 开发

public class HelloClient {

public void connect(String host, int port) {

EventLoopGroup eventLoopGroup = new NioEventLoopGroup();

Bootstrap bootstrap = new Bootstrap(); //注意和 server 的区别

bootstrap.group(eventLoopGroup);

bootstrap.channel(NioSocketChannel.class);//注意和 server 端的区别，server 端是 NioServerSocketChannel

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

protected void initChannel(SocketChannel socketChannel) throws Exception {

ChannelPipeline pipeline = socketChannel.pipeline();

pipeline.addLast(new HelloClientIntHandler());

}

});

bootstrap.option(ChannelOption.SO_KEEPALIVE, true);

try {

// Start the client.

ChannelFuture future = bootstrap.connect(host, port).sync();

// 等待服务器 socket 关闭。

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

} catch (InterruptedException e) {

e.printStackTrace();

} finally {

eventLoopGroup.shutdownGracefully();

}

public static void main(String[] args) {

HelloClient client = new HelloClient();

client.connect("127.0.0.1", 8080);

}

client 消息处理

public class HelloClientIntHandler extends ChannelInboundHandlerAdapter {

// 连接成功后，向server发送消息

@Override

public void channelActive(ChannelHandlerContext ctx) throws Exception {

System.out.println("connected server. start send msg.");

String msg = "r u ok?";

ByteBuf encoded = ctx.alloc().buffer(4 * msg.length());

encoded.writeBytes(msg.getBytes());

ctx.writeAndFlush(encoded);

}

// 接收server端的消息，并打印出来

@Override

public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {

try {

ByteBuf result = (ByteBuf) msg;

byte[] serverMsg = new byte[result.readableBytes()];

result.readBytes(serverMsg);

System.out.println("Server said:" + new String(serverMsg));

} finally {

ReferenceCountUtil.release(msg);

}

测试

分别启动server端和client端

server端会输出如下内容：

client send msg: r u ok?

client端会输出如下内容：

Server said:i am ok!

本文转自秋楓博客园博客，原文链接：http://www.cnblogs.com/rwxwsblog/p/7742597.html，如需转载请自行联系原作者