【Java】【Socket】通过DatagramPacket发送接收UDP组播

        //创建组播
        InetAddress groupAddress = InetAddress.getByName("239.0.0.1");
        MulticastSocket socket = new MulticastSocket(10010);
        socket.joinGroup(groupAddress);
        //接收数据
        byte[] data = new byte[1024 * 1024];
        DatagramPacket receivePacket = new DatagramPacket(data, data.length, groupAddress, 10010);
        socket.receive(receivePacket);
        String message = new String(receivePacket.getData()).trim();
        //回复数据
        String response = "ok";
        DatagramPacket replyPacket = new DatagramPacket(response.getBytes(), response.getBytes().length, receivePacket.getAddress(), receivePacket.getPort());
        socket.send(replyPacket);