import java.net.*;
import java.io.*;
class UDPClient{
    public static void main(String args[]){ 
	// args give message contents and server hostname
	DatagramSocket aSocket = null;
	try {
	    aSocket = new DatagramSocket();    
	    byte [] m = args[0].getBytes();
	    InetAddress aHost = InetAddress.getByName(args[1]);
	    int serverPort = 6789;                                                 
	    DatagramPacket request = new DatagramPacket(m,  args[0].length(), aHost, serverPort);
	    aSocket.send(request);                        
	    byte[] buffer = new byte[1000];
	    DatagramPacket reply = new DatagramPacket(buffer, buffer.length);
	    aSocket.receive(reply);
	    System.out.println("Reply: " + new String(reply.getData()));
	}
	catch (SocketException e){System.out.println("Socket: " + e.getMessage());}
	catch (IOException e){System.out.println("IO: " + e.getMessage());}
        finally {if(aSocket != null) aSocket.close();}
    }
}