Java tutorial
import java.net.DatagramPacket; import java.net.DatagramSocket; import java.net.InetAddress; public class Main { private final static int BUFSIZE = 20; public static void main(String args[]) { try { int port = 80; DatagramSocket ds = new DatagramSocket(port); byte buffer[] = new byte[BUFSIZE]; while (true) { DatagramPacket dp = new DatagramPacket(buffer, buffer.length); // Receive data ds.receive(dp); // Display address from the datagram packet InetAddress ia = dp.getAddress(); System.out.println(ia); System.out.println(dp.getSocketAddress()); } } catch (Exception e) { e.printStackTrace(); } } }