Getting the time using UDP

Question

I have the following class (source code from java core tips):
public class GetTime {
     final private static int DAYTIME_PORT = 13;
     public static void main(String args[]) throws
     IOException {
          if (args.length == 0) {
               System.err.println
               ("Please specify daytime host");
               System.exit(-1);
          String host = args[0];
          byte message[] = new byte[256];
          InetAddress address = InetAddress.getByName(host);
          System.out.println("Checking at: " + address);
          DatagramPacket packet =
               new DatagramPacket(message, message.length,
                         address, DAYTIME_PORT);
          DatagramSocket socket = new DatagramSocket();
          socket.send(packet);
          packet =
               new DatagramPacket(message, message.length);
          socket.receive(packet);
          String time = new String(packet.getData());
          System.out.println("The time at" + host + " is: " + time);
          socket.close();
I am running this code but it does not show me the time. The host is the 'localhost'. I read that upon a connection to port 13 a response with the data and time should be automatically sent. By me it just prompts this: "Checking at: localhost/127.0.0.1" and it remains like that while it's still running...
Can anyone tell me what it's wrong. I've tried instead of localhost to give a time server name and changed the port number but it still doesn't work.

Answer 1

Is the Server running and listening on port 13????