import java.io.*;
import java.net.*;

public class TimeServer {

    // server port
    static private final int port = 6789;

    public static void main(String[] args) {

        // multicast address
        String dategroup;

        // get the multicast address in input
        dategroup = args[0];

        DatagramSocket ms = null;

        System.out.println("S> Server ready");

        try {
            // create inet address
            InetAddress ia = InetAddress.getByName(dategroup);

            byte [] data;
            long time;

            // create the datagram socket
            ms = new DatagramSocket(2000);

            // infinite cycle
            while(true) {
                // get the time
                time = System.currentTimeMillis();

                // convert the time in a String, then in byte array
                data = Long.toString(time).getBytes();

                // create the datagram packet to send
                DatagramPacket dp = new DatagramPacket(data, data.length, ia, port);

                // send the packet
                ms.send(dp);

                // sleep a bit
                try {
                    Thread.sleep(3000);
                }
                catch(InterruptedException e) {
                    System.out.println("S> INTERROTTO: " + e.toString());
                }

            }
        }
        catch(IOException e) {
            System.out.println("S> ERROR: "+e.toString());
        }
        finally {
            // close datagram socket in case of exception
            if(ms != null)
                ms.close();
        }

    }

}