Netty入门服务端&客户端demo

服务端

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

// 自定义网络服务器
public class MySimpleServer {
    public static void main(String[] args) throws InterruptedException {
        ServerBootstrap sb = new ServerBootstrap();
        NioEventLoopGroup group = new NioEventLoopGroup();
        try {
            sb.group(group);
            sb.channel(NioServerSocketChannel.class);
            sb.localAddress(8090);
            sb.childHandler(new MySimpleChannelInitializer());
            ChannelFuture future = sb.bind();
            future.sync().channel().closeFuture().sync();
        } finally {
            group.shutdownGracefully().sync();
        }

    }
}
// 通道初始化
class MySimpleChannelInitializer extends ChannelInitializer<SocketChannel> {

    @Override
    protected void initChannel(SocketChannel ch) throws Exception {
        // 增加字符串编解码器，否则自定义消息处理器无法解析字节数据
        ch.pipeline().addLast(new StringDecoder());
        ch.pipeline().addLast(new StringEncoder());
        // 将自定义服务器消息处理器加入通道
        ch.pipeline().addLast(new MySimpleHandler());
    }

}
// 消息处理器
class MySimpleHandler extends SimpleChannelInboundHandler<String> {
    // 读取消息
    @Override
    protected void channelRead0(ChannelHandlerContext ctx, String msg) throws Exception {
        System.out.println("Server Receive:" + msg);
        ctx.writeAndFlush("this is server");
    }
}

客户端

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

import java.net.InetSocketAddress;

public class MySimpleClient {
    public static void main(String[] args) throws InterruptedException {
        Bootstrap bs = new Bootstrap();
        NioEventLoopGroup group = new NioEventLoopGroup();
        try {
            bs.group(group);
            bs.channel(NioSocketChannel.class);
            bs.handler(new MyClientChannelInitializer());
            ChannelFuture future = bs.connect(new InetSocketAddress("localhost", 8090));
            future.sync().channel().closeFuture().sync();
        } finally {
            group.shutdownGracefully().sync();
        }

    }
}

// 客户端通道初始化
class MyClientChannelInitializer extends ChannelInitializer<SocketChannel> {
    @Override
    protected void initChannel(SocketChannel ch) throws Exception {
        // 增加字符串编解码器，否则自定义消息处理器无法解析字节数据
        ch.pipeline().addLast(new StringDecoder());
        ch.pipeline().addLast(new StringEncoder());
        // 将客户端消息处理器加入通道中
        ch.pipeline().addLast(new MyClientHandler());
    }
}

// 自定义客户端消息处理器
class MyClientHandler extends SimpleChannelInboundHandler<String> {
    @Override
    public void channelActive(ChannelHandlerContext ctx) throws Exception {
        ctx.writeAndFlush("hello ,this is client");
    }

    @Override
    protected void channelRead0(ChannelHandlerContext channelHandlerContext, String string) throws Exception {
        //
        System.out.println("Client Receive:" + string);
    }
}