UDP广播无法正常工作

Question

我的要求是从服务器向所有连接的客户端广播UDP消息。

我正在使用netty 4.x.x来实现客户端服务器。我不是我无法将消息广播到所有连接的客户端。

服务器代码

public class UDPServer {

    private static final Logger logger = LogManager.getLogger(UDPServer.class.getName());

    private final ServerConfig conf;

    /*
     * Constructor of Server class 
     */
    public UDPServer(ServerConfig conf) {
        this.conf = conf;


    public void run() throws Exception {

        EventLoopGroup bossGroup = new NioEventLoopGroup();
        EventLoopGroup workerGroup = new NioEventLoopGroup();

        try {


        EventLoopGroup udpGroup = new NioEventLoopGroup();
        try {

            Bootstrap b = new Bootstrap();
            b.group(udpGroup)
                    .channel(NioDatagramChannel.class)                    
                    .handler(new ChannelInitializer<DatagramChannel>() {
                        @Override
                        protected void initChannel(DatagramChannel ch) throws Exception {
                            ChannelPipeline p = ch.pipeline();
                            p.addLast("udpDecoder", new MessageToMessageDecoder<DatagramPacket>() {

                                @Override
                                protected void decode(ChannelHandlerContext ctx, DatagramPacket msg, List<Object> out) throws Exception {
                                    out.add(msg.content());
                                    msg.retain();
                                }
                            });
                            p.addLast("handler", new UDServerPHandler());
                            p.addLast("frameDecoder", new LengthFieldBasedFrameDecoder(65535, 2, 2));
                        }
                    })
                    .option(ChannelOption.SO_BROADCAST, true);

          //  b.bind(9998).sync().channel().closeFuture().sync();
              b.bind(9998).channel().closeFuture().sync();
        } finally {
            udpGroup.shutdownGracefully();
        }
    }

    /**
     * Main method to run the class
     *
     * @param args
     * @throws Exception
     */
    public static void main(String[] args) throws Exception {
        new UDPServer(new ServerConfig()).run();
    }

}

服务器处理程序

package com.quantotrade.shamse.udp;
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.SimpleChannelInboundHandler;
import io.netty.channel.socket.DatagramPacket;
import io.netty.util.CharsetUtil;

import java.util.Random;

public class UDServerPHandler extends SimpleChannelInboundHandler<DatagramPacket> {

    private static final Random random = new Random();

    private static final String[] quotes = {
        "ONE",
        "TWO",
        "THREE",
        "FOUR",
    };

    private static String nextQuote() {
        int quoteId;
        synchronized (random) {
            quoteId = random.nextInt(quotes.length);
        }
        return quotes[quoteId];
    }

    @Override
    protected void channelRead0(ChannelHandlerContext ctx, DatagramPacket packet) throws Exception {
        //System.err.println(packet.content().toString(CharsetUtil.UTF_8));
        //if ("Quote".equals(packet.content().toString(CharsetUtil.UTF_8))) {
          //  ctx.write(new DatagramPacket(Unpooled.copiedBuffer("Quote" + nextQuote(), CharsetUtil.UTF_8), packet.sender()));
            ctx.channel().writeAndFlush(new DatagramPacket(Unpooled.copiedBuffer("Quote" + nextQuote(), CharsetUtil.UTF_8), packet.sender()));

        //}
    }



    @Override
    public void channelReadComplete(ChannelHandlerContext ctx) {
        ctx.flush();
    }
}

客户代码

public class UDPClientHandler extends SimpleChannelInboundHandler<DatagramPacket> {

    //private final EventExecutor executor = new NioEventLoopGroup();
    //private final ChannelGroup channels = new DefaultChannelGroup();

    @Override
    protected void channelRead0(ChannelHandlerContext ctx, DatagramPacket msg) throws Exception {
        String response = msg.content().toString(CharsetUtil.UTF_8);
        if (response.startsWith("Quote")) {
            System.out.println("Quote:" + response.substring(5));
            //ctx.writeAndFlush(new DatagramPacket(Unpooled.copiedBuffer("Quote", CharsetUtil.UTF_8), msg.sender()));
           // channels.add(ctx.channel());
        }
    }

请帮助