Netty UDP协议网络打洞实例

package com.hh.common.codec; import java.net.InetSocketAddress; import com.hh.common.server.UdpServer; import io.netty.buffer.ByteBuf; import io.netty.buffer.Unpooled; import io.netty.channel.Channel; import io.netty.channel.ChannelHandlerContext; import io.netty.channel.SimpleChannelInboundHandler; import io.netty.channel.socket.DatagramPacket; import lombok.extern.slf4j.Slf4j; @Slf4j public class UdpDecoder extends SimpleChannelInboundHandler<DatagramPacket>{ private InetSocketAddress inetAddress; private Channel ch ; @Override protected void channelRead0(ChannelHandlerContext ctx, DatagramPacket msg) throws Exception { // 接受client的消息 // log.info("开始接收来自client的数据"); final ByteBuf buf = msg.content(); int readableBytes = buf.readableBytes(); byte[] content = new byte[readableBytes]; buf.readBytes(content); String clientMessage = new String(content,"GBK"); if(clientMessage.contains("UDP_MAIN_CHANNEL_CLIENT")){ inetAddress=msg.sender(); }else{ ctx.writeAndFlush(new DatagramPacket(Unpooled.wrappedBuffer(content),this.inetAddress)); } log.info("msg recv :{}",clientMessage); // ch.writeAndFlush(new DatagramPacket(Unpooled.wrappedBuffer(("channel"+ch.id()+":helloClient").getBytes()),msg.sender())); } public UdpDecoder() { super(); } public UdpDecoder(Channel ch,InetSocketAddress inetAddress) { super(); this.ch=ch; this.inetAddress = inetAddress; } @Override public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception { // TODO Auto-generated method stub cause.printStackTrace(); super.exceptionCaught(ctx, cause); } // /** // * 发送数据包并监听结果 // * @param datagramPacket // */ // public static void senderInternal(final DatagramPacket datagramPacket,List<Channel> channelList) { // for (Channel channel : NettyTCPClient.channelList) { // if(channel != null){ // channel.writeAndFlush(datagramPacket).addListener(new GenericFutureListener<ChannelFuture>() { // @Override // public void operationComplete(ChannelFuture future) // throws Exception { // boolean success = future.isSuccess(); // if(logger.isInfoEnabled()){ // logger.info("Sender datagramPacket result : "+success); // } // } // }); // } // } // } // // /** // * 组装数据包 // * @param msg 消息串 // * @param inetSocketAddress 服务器地址 // * @return DatagramPacket // */ // private static DatagramPacket datagramPacket(String msg, InetSocketAddress inetSocketAddress){ // ByteBuf dataBuf = Unpooled.copiedBuffer(msg,Charset.forName("UTF-8")); // DatagramPacket datagramPacket = new DatagramPacket(dataBuf, inetSocketAddress); // return datagramPacket; // } // // /** // * 发送数据包服务器无返回结果 // * @param datagramPacket // */ // private static void senderInternal(final DatagramPacket datagramPacket) { // logger.info("LogPushUdpClient.channel"+LogPushUdpClient.channel); // if(LogPushUdpClient.channel != null){ // LogPushUdpClient.channel.writeAndFlush(datagramPacket).addListener(new GenericFutureListener<ChannelFuture>() { // @Override // public void operationComplete(ChannelFuture future) // throws Exception { // boolean success = future.isSuccess(); // if(logger.isInfoEnabled()){ // logger.info("Sender datagramPacket result : "+success); // } // } // }); // }else{ // throw new NullPointerException("channel is null"); // } // } }