模拟器中未收到来自本地主机的 UDP 数据包

My app is unable to receive the UDP packets when running in the emulator. UDP packets are sent by below java program on "localhost" over the port 49999.

    DatagramSocket clientsocket;
        DatagramPacket dp;
        BufferedReader br;
        InetAddress ia;
        byte buf[] = new byte[1024];
        int cport = 50000, sport = 49999;

        clientsocket = new DatagramSocket(cport);
        dp = new DatagramPacket(buf, buf.length);
        br = new BufferedReader(new InputStreamReader(System.in));
        ia = InetAddress.getLocalHost();

        while(true)
        {
            Random rand = new Random();
            String str1 = rand.nextInt(100) + "";
            buf = str1.getBytes();

            System.out.println("Sending " + str1);
            clientsocket.send(new DatagramPacket(buf,str1.length(), ia, sport));

            try{
                Thread.sleep(100);
            } catch(Exception e){}
        }

在同一本地主机上运行的另一个 java UDP 服务器程序可以正常接收数据包.这意味着数据包被正确发送到 localhost:49999.

telnet localhost 49999
redir add udp:49999:49999

byte[] data = new byte[1400];
DatagramPacket packet = new DatagramPacket(data, 1400);
DatagramSocket socket = new DatagramSocket(49999);
socket.setSoTimeout(200);
try{
socket.receive(packet);  ---->> This throws a SocketTimeoutException
} catch(SocketTimeoutException e){}