// DgmSend.java sends a little UDP message via DatagramPacket import java.net.*; import java.io.*; class DgmSend { static final int PORT = 3030; public static void main(String[] args) throws Exception { String msg = (args.length > 0) ? args[0] : "DatagramDemo"; InetAddress dest = InetAddress.getByName( (args.length > 1) ? args[1] : "127.0.0.1" ); DatagramSocket sock = new DatagramSocket(); byte[] buf = msg.getBytes(); DatagramPacket pack = new DatagramPacket(buf, buf.length, dest, PORT); sock.send(pack); } }