Client Server Communication using UDP

UDP_Server.java

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

public class UDP_Server {

    public static void main(String args[]) {
        DatagramSocket dgSocket = null;
        if (args.length < 1) {
            System.out.println("UDP_Server");
            System.exit(1);
        }
        try {
            int socket_no = Integer.valueOf(args[0]).intValue();
            dgSocket = new DatagramSocket(socket_no);
            byte[] buffer_array = new byte[1000];
            while (true) {
                DatagramPacket request = new DatagramPacket(buffer_array, buffer_array.length);
                dgSocket.receive(request);
                DatagramPacket reply = new DatagramPacket(request.getData(), request.getLength(), request.getAddress(), request.getPort());
                dgSocket.send(reply);
            }
        } catch (SocketException e) {
            System.out.println("Socket : " + e.getMessage());
        } catch (IOException e) {
            System.out.println("i/o: " + e.getMessage());
        } finally {
            if (dgSocket != null) {
                dgSocket.close();
            }
        }
    }
}

        
  

UDP_Client.java

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

public class UDP_Client {

    public static void main(String args[]) {

        DatagramSocket dgSocket = null;
        if (args.length < 3) {
            System.out.println("UDP_Client   ");
            System.exit(1);
        }
        try {
            dgSocket = new DatagramSocket();
            byte[] m = args[0].getBytes();
            InetAddress hostAdr = InetAddress.getByName(args[1]);
            int serverPort = Integer.valueOf(args[2]).intValue();
            DatagramPacket request
                    = new DatagramPacket(m, args[0].length(), hostAdr, serverPort);
            dgSocket.send(request);
            byte[] buffer = new byte[1000];
            DatagramPacket dgRreply = new DatagramPacket(buffer, buffer.length);
            dgSocket.receive(dgRreply);
            System.out.println("Reply: " + new String(dgRreply.getData()));
        } catch (SocketException e) {
            System.out.println("Socket: " + e.getMessage());
        } catch (IOException e) {
            System.out.println("i/o " + e.getMessage());
        } finally {
            if (dgSocket != null) {
                dgSocket.close();
            }
        }
    }
}