netty 底层的工作原理

喜欢ヅ旅行 2024-03-31 15:56 72阅读 0赞

#### 什么是 Netty ####

Netty 是一个高性能的网络通信框架，封装了底层复杂的 socket 编程细节，让我们可以高效快速构建自己的应用

有哪些开源框架用了 Netty 呢？grpc、dubbo、kafka、rocketmq、zookeeper、hadoop

#### Netty Demo ####

**server 端启动 netty 服务器**

public static void main(String[] args) throws InterruptedException {
        EventLoopGroup boss = new NioEventLoopGroup();
        EventLoopGroup worker = new NioEventLoopGroup();
        try {
            ServerBootstrap serverBootstrap = new ServerBootstrap();
            serverBootstrap.group(boss, worker)
                    .channel(NioServerSocketChannel.class)
                    // 设置接收缓冲区大小
                        // 控制窗口值
                    .childOption(ChannelOption.SO_RCVBUF, 32 * 1024)
                    // 设置发送缓冲区大小
                    .childOption(ChannelOption.SO_SNDBUF, 32 * 1023)
                    .childHandler(new ChannelInitializer<SocketChannel>() {
                        @Override
                        protected void initChannel(SocketChannel ch) throws Exception {
                            ChannelPipeline channelPipeline = ch.pipeline();
                            channelPipeline.addLast(new JdrpcCodec());
                            channelPipeline.addLast(new JdrpcServerHandler());
                        }
                    });
            ChannelFuture channelFuture = serverBootstrap.bind(JdrpcConstant.PORT).sync();
    
            channelFuture.addListener(future -> {
               if (future.isSuccess()) {
                   logger.info("服务启动成功，绑定端口: {}", JdrpcConstant.PORT);
               } else {
                   logger.error("服务启动失败");
               }
            });
            channelFuture.channel().closeFuture().sync();
    
        } finally {
            boss.shutdownGracefully();
            worker.shutdownGracefully();
        }
    }

**启动 client**

public static void main(String[] args) throws InterruptedException {
        EventLoopGroup eventLoopGroup = new NioEventLoopGroup();
        Bootstrap bootstrap = new Bootstrap();
        bootstrap.group(eventLoopGroup)
                .channel(NioSocketChannel.class)
                    // 连接超时时间
                .option(ChannelOption.CONNECT_TIMEOUT_MILLIS, 5000)
                // 保持长连接心跳
                .option(ChannelOption.SO_KEEPALIVE, true)
                // 禁用 Nagle 算法
                .option(ChannelOption.TCP_NODELAY, true)
                .handler(new ChannelInitializer<SocketChannel>() {
                    @Override
                    protected void initChannel(SocketChannel ch) throws Exception {
                        ch.pipeline()
                                    // 设置编码解码器
                                .addLast(new JdrpcCodec())
                                // 业务逻辑处理类
                                .addLast(new JdrpcClientHandler());
                    }
                });
        bootstrap.connect("127.0.0.1", JdrpcConstant.PORT).addListener(future -> {
            if (future.isSuccess()) {
                logger.info("连接成