5-UDPS.java

// Write a program on datagram socket for client/server to display the messages on client side, typed at the server side.

import java.util.*;
import java.net.*;

public class UDPS{
	public static void main(String[] args) throws Exception{
		DatagramSocket serverSocket=new DatagramSocket(9876);
		System.out.println("Server is ready for connection");
		byte[] receiveData=new byte[1024];
		byte[] sendData=new byte[1024];
		
		while(true){
			DatagramPacket receivePacket=new DatagramPacket(receiveData,receiveData.length);
			serverSocket.receive(receivePacket);
			String sentence=new String(receivePacket.getData());
			System.out.println("RECEIVED: "+sentence);
			
			InetAddress IPAddress=receivePacket.getAddress();
			int port=receivePacket.getPort();
			String capitalizedSentence=sentence.toUpperCase();
			sendData=capitalizedSentence.getBytes();
			DatagramPacket sendPacket=new DatagramPacket(sendData,sendData.length,IPAddress,port);
			serverSocket.send(sendPacket);
		}
	}
}