java写netty客户端

下面是一个简单的Java Netty客户端示例代码：

import io.netty.bootstrap.Bootstrap;
import io.netty.channel.Channel;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.ChannelOption;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.SocketChannel;
import io.netty.channel.socket.nio.NioSocketChannel;

public class NettyClient {
    private final String host;
    private final int port;

    public NettyClient(String host, int port) {
        this.host = host;
        this.port = port;
    }

    public void run() throws Exception {
        NioEventLoopGroup group = new NioEventLoopGroup();
        try {
            Bootstrap bootstrap = new Bootstrap()
                    .group(group)
                    .channel(NioSocketChannel.class)
                    .option(ChannelOption.SO_KEEPALIVE, true)
                    .handler(new ChannelInitializer<SocketChannel>() {
                        @Override
                        protected void initChannel(SocketChannel socketChannel) throws Exception {
                            socketChannel.pipeline().addLast(new NettyClientHandler());
                        }
                    });

            ChannelFuture future = bootstrap.connect(host, port).sync();
            Channel channel = future.channel();
            channel.closeFuture().sync();
        } finally {
            group.shutdownGracefully();
        }
    }

    public static void main(String[] args) throws Exception {
        String host = "localhost";
        int port = 8080;
        NettyClient client = new NettyClient(host, port);
        client.run();
    }
}

其中，NettyClientHandler是自定义的ChannelHandler，用于处理接收到的消息，在这里你可以根据自己的需求进行实现。