Tuesday, May 29, 2012

Datagram Client in Java

This Example is implementation of Datagram Client or UDP client purpose of this example is to provide a fare idea about the working of UDP client server this client example works with server example and link to server example is given at the end of this code example works on the concept of UDP protocol (simple transmission model without implicit handshaking)

import java.io.*;

import java.net.*;

public class Client {

    public static void main(String[] args) {

      DatagramSocket clientSkt = null;

      InetAddress IPAdd = null;

      String text =null;

      DatagramPacket receivePkt= null;

      BufferedReader inFromUser =

         new BufferedReader(new InputStreamReader(System.in));

      try{

      clientSkt = new DatagramSocket();

      IPAdd = InetAddress.getByName("localhost");

      }

      catch(SocketException exp){

          System.out.println(exp);

      }

      catch(UnknownHostException exp){

          System.out.println(exp);

      }      

      byte[] sendData = new byte[1024];

      byte[] receiveData = new byte[1024];

      try{

      text = inFromUser.readLine();

      sendData = text.getBytes();

      DatagramPacket sendPacket = new DatagramPacket(sendData, sendData.length, IPAdd, 3030);

      clientSkt.send(sendPacket);

      receivePkt = new DatagramPacket(receiveData, receiveData.length);

      clientSkt.receive(receivePkt);

      }

      catch(IOException exp){

          System.out.println(exp);

      }

      String modifiedSentence = new String(receivePkt.getData());

      System.out.println("FROM SERVER:" + modifiedSentence);

      clientSkt.close();

    }

}

Datagram Server Source

Datagram Server in Java

This example is about Datagram Server or UDP server purpose of this example is to provide a fare idea about the working of UDP client server this server example works with client example and link to the client example is given at the end of this code example works on the concept of UDP protocol (simple transmission model without implicit handshaking)


import java.io.*;

import java.net.*;

public class Server {

    public static void main(String[] args) {

        DatagramSocket serverSkt= null;

        try{

            serverSkt = new DatagramSocket(3030);

        }

        catch(SocketException exp)

        {

            System.out.println(exp);

        }

        byte[] receiveData = new byte[1024];

        byte[] sendData = new byte[1024];

        while(true)

          {

            DatagramPacket receivePkt = new DatagramPacket(receiveData, receiveData.length);

            try{

                serverSkt.receive(receivePkt);

            }

            catch(IOException exp)

            {

                System.out.println(exp);

            }

            String sentence = new String( receivePkt.getData());

            System.out.println("RECEIVED: " + sentence);

            InetAddress IPAddress = receivePkt.getAddress();

            int port = receivePkt.getPort();

            String capitalizedSentence = sentence.toUpperCase();

            sendData = capitalizedSentence.getBytes();

            DatagramPacket sendPkt =

            new DatagramPacket(sendData, sendData.length, IPAddress, port);

            try{

            serverSkt.send(sendPkt);

            }

            catch(IOException exp)

            {

                System.out.println(exp);

            }   

        }

      }        

  }
Datagram Client Source

Friday, February 10, 2012

Get Your PC's IP Address in Java

This example returns IP address of your PC.

import java.net.*;

public class TellMyIP {

public static void main(String[] args) {

 InetAddress localHostIP= null;

   //creates instance of InetAddress

  try{

  localHostIP=InetAddress.getLocalHost();

  //initializes localHostIP

  System.out.println("IP ADDRESS OF MY PC IS = "+localHostIP.getHostAddress());

  //gets IP address and prints it

  }catch (Exception exception){

  System.out.println("Something that went wrong is :"+exception.getMessage());

  }

   }

}