MultiCast Messaging in Java

Sending the file or message to a set of clients or group of clients

import java.awt.*;
import java.awt.event.*;
import java.net.*;
import javax.swing.JFrame;

public class Multicast extends JFrame implements ActionListener,Runnable{
 Label entermsgl,receivedmsgl,sentmsgl;
 TextField entermsg;
 TextArea receivedmsg,sentmsg;
 Button Multicast,exit;
 int myport;
 MulticastSocket ms_send,ms_receive;
 DatagramPacket dp;
 InetAddress address;
 Thread t;
 Multicast(){
  initialise();
 }
 public void initialise(){
  setTitle("Multicast ");
  setVisible(true);
  setSize(600,400);
  entermsgl=new Label("Enter Message:");
  receivedmsgl=new Label("Received Messages:");
  sentmsgl=new Label("Sent Messages:");
  entermsg=new TextField();
  receivedmsg=new TextArea();
  sentmsg=new TextArea();
  Multicast=new Button("Multicast");
  exit=new Button("Exit");
  setLayout(null);
  add(entermsgl);
  entermsgl.setBounds(25,25,100,25);
  add(receivedmsgl);
  receivedmsgl.setBounds(25,70,150,25);
  add(sentmsgl);
  sentmsgl.setBounds(25,185,150,25);
  add(entermsg);
  entermsg.setBounds(130,25,200,25);
  add(receivedmsg);
  receivedmsg.setBounds(180,70,370,100);
  add(sentmsg);
  sentmsg.setBounds(180,185,370,100);
  add(Multicast);
  Multicast.setBounds(470,25,100,25);
  add(exit);
  exit.setBounds(250,300,100,25);
  try{
   address=InetAddress.getByName("230.150.150.15");
   ms_send=new MulticastSocket();
   ms_receive=new MulticastSocket(2001);
   ms_receive.joinGroup(address);
  }catch(Exception e){
   System.out.println(e);
  }
  Multicast.addActionListener(this);
  exit.addActionListener(this);
  t=new Thread(this);
  t.start();
 }
 //class Receive extends Thread{
 // Receive(){
  // start();
  //}
  public void run(){
   while(true){
    System.out.println("1");
    try{
     DatagramPacket dp1;
     byte b[]=new byte[100];
     System.out.println("2");
     dp1=new DatagramPacket(b,b.length);
     ms_receive.receive(dp1);
     System.out.println("3");
     receivedmsg.append("From "+dp1.getAddress()+" "+dp1.getPort()+": "+new String(dp1.getData(),0,dp1.getLength())+"\n");
     repaint();
    }catch(Exception e){
     System.out.println(e);
    }
   }
   
  }
 //}
 public void actionPerformed(ActionEvent ae){
  if(ae.getSource()==Multicast){
   byte b[]=entermsg.getText().getBytes();
   try{
    dp=new DatagramPacket(b,b.length,address,2001);
    ms_send.send(dp,(byte)1);
    sentmsg.append(ms_send.getLocalAddress()+" port:"+ms_send.getLocalPort()+": "+entermsg.getText()+"\n");
   }catch(NumberFormatException nfe){
   }catch(Exception e){
    System.out.println(e);
   }
  }
  else{
   System.exit(0);
  }
 }
 public static void main(String args[]){
  new Multicast();
 }

}