Net Conference

Title A Simple Client-Server Multicasting Author S Balasubramanian Author Email spbalu_2k [at] yahoo.com Description NetConference Implementing 1-2-M Conference, Means One Server Responds to Many Clients. It Provides users about Basic Info about Netconference, Multicasting aswell as Multitherading in Java. Category Java � Networking Hits 13268 Code : /* Client Setting NetConference. ______________ */ /* Tips to run this : __________________ (After compiling chatkaro12mserver.java) Step1: Open another prompt and run java chatkaro12mclient ___________________________________ */ /* Server Setting ** NetConference** __________________ */ /* Tips to run this: __________________ Step1: Open command prompt and run java chatkaro12mserver. ______________________ Step2: Continue with client program. */ //Code: chatkaro12mserver.java // Program Starts... import java.io.*;

127.0.0.1.

import java.net.*; import java.util.Vector; import java.util.Enumeration; public class chatkaro12mServer { //static String k=socket.getInetAddress().getHostName(); private int port=5001; private boolean li=true; private Vector clients=new Vector(); public static void main(String a[]) { System.out.println(" Press ctrl-c to Quit."); new chatkaro12mServer().server(); } void server() { ServerSocket serverSock=null; try { InetAddress serverAddr=InetAddress.getByName(null); System.out.println("Waiting for"+serverAddr.getHostName()+"on port"+port); serverSock=new ServerSocket(port,50); } catch(IOException e) { System.out.println(e.getMessage()+":Failed"); return; } while(li) { try { Socket socket=serverSock.accept(); System.out.println("Accept "+socket.getInetAddress().getHostName()); DataOutputStream remoteOut= new DataOutputStream(socket.getOutputStream()); clients.addElement(remoteOut); new ServerHelper(socket,remoteOut,this).start(); } catch(IOException e) { System.out.println(e.getMessage()+":Failed"); } } if(serverSock !=null) { try { serverSock.close(); } catch(IOException x) { } } } synchronized Vector getClients()

{ return clients; } synchronized void removeFromClients(DataOutputStream remoteOut) { clients.removeElement(remoteOut); } } class ServerHelper extends Thread { private Socket sock; private DataOutputStream remoteOut; private chatkaro12mServer server; private boolean li=true; private DataInputStream remoteIn; ServerHelper(Socket sock,DataOutputStream remoteOut,chatkaro12mServer server) throws IOException { this.sock=sock; this.remoteOut=remoteOut; this.server=server; remoteIn=new DataInputStream(sock.getInputStream()); } public synchronized void run() { String s; try { while(li) { s=remoteIn.readUTF(); broadcast(s); } } catch(IOException e) { System.out.println(e.getMessage()+"connection lost"); } finally { try { cleanUp(); } catch (IOException x) { } } } private void broadcast(String s) { Vector clients=server.getClients(); DataOutputStream dataOut=null; for(Enumeration e=clients.elements(); e.hasMoreElements(); ) { dataOut=(DataOutputStream)(e.nextElement()); if(!dataOut.equals(remoteOut))

{ try { dataOut.writeUTF(s); } catch(IOException x) { System.out.println(x.getMessage()+"Failed"); server.removeFromClients(dataOut); } } } } private void cleanUp() throws IOException { if(remoteOut!=null) { server.removeFromClients(remoteOut); remoteOut.close(); remoteOut=null; } if(remoteIn!=null) { remoteIn.close(); remoteIn=null; } if(sock!=null) { sock.close(); sock=null; } } protected void finalize() throws Throwable { try { cleanUp(); } catch(IOException x) { } super.finalize(); } } Code: chatkaro12mclient.java // Program Starts... import import import import import

java.io.*; javax.swing.*; java.net.*; java.awt.*; java.awt.event.*;

public class chatkaro12mClient extends Panel { TextArea receivedText; Socket sock; private GridBagConstraints c; private GridBagLayout gridBag; private Frame frame; private Label label; JButton send; JButton exit; private int port=5001; private TextArea sendText; private String hostname; private String username; private DataOutputStream remoteOut; ImageIcon i1,i2; public static void main(String args[]) { if(args.length != 2) { System.out.println("Format is : java chatkaro12mClient "); return; } Frame f1=new Frame("Welcome Protocol"); f1.resize(800,600); f1.show(); JOptionPane.showMessageDialog(f1,"Welcome "+args[0]+".. Have a nice Session.","Welcome",0); Frame f= new Frame("Connecting to Mr. "+args[0]); chatkaro12mClient chat=new chatkaro12mClient(f,args[0],args[1]); f.add("Center",chat); f.setSize(800,600); f.show(); chat.client(); } public chatkaro12mClient(Frame f,String user,String host) { frame=f; frame.addWindowListener(new WindowExitHandler()); username=user; hostname=host; //Insets insets=new Insets(10,20,5,10); //gridBag=new GridBagLayout(); //setLayout(gridBag); /*c=new GridBagConstraints(); c.insets=insets; c.gridy=0; c.gridx=0;*/ label=new Label("Text to send :"); add(label); /*gridBag.setConstraints(label,c); c.gridx=1;*/ sendText=new TextArea(15,30); /*sendText.addActionListener(new TextActionHandler()); gridBag.setConstraints(sendText,c);*/ add(sendText); //c.gridy=1;

//c.gridx=0; label= new Label("Text received :"); //gridBag.setConstraints(label,c); add(label); //c.gridx=1; receivedText=new TextArea(15,30); //gridBag.setConstraints(receivedText,c); add(receivedText); ImageIcon i1=new ImageIcon("click.gif"); ImageIcon i2=new ImageIcon("doorin2.gif"); send=new JButton(i1); exit=new JButton(i2); add(send); add(exit); send.addActionListener(new TextActionHandler()); exit.addActionListener(new EXIT()); } void client() { try { if(hostname.equals("local")) hostname=null; InetAddress serverAddr= InetAddress.getByName(hostname); sock=new Socket(serverAddr.getHostName(),port); remoteOut=new DataOutputStream(sock.getOutputStream()); System.out.println("Connected to server " + serverAddr.getHostName() + " on port " + sock.getPort()); new chatkaro12mClientReceive(this).start(); } catch(IOException e) { System.out.println(e.getMessage() + " : Failed to connect to server."); } } protected void finalize() throws Throwable { try { if(remoteOut != null) remoteOut.close(); if(sock != null) sock.close(); } catch(IOException x) {} super.finalize(); } class WindowExitHandler extends WindowAdapter { public void windowClosing(WindowEvent e) { Window w=e.getWindow(); w.setVisible(false); w.dispose();

System.exit(0); } } class EXIT implements ActionListener { public void actionPerformed(ActionEvent e) { if((JOptionPane.showConfirmDialog(new Frame(),"Are You Sure to close the Session?"))==JOptionPane.YES_OPTION) { JOptionPane.showMessageDialog(new Frame(),"Thank U. Visit Again. ","Good Bye",0); System.exit(0); } } } class TextActionHandler implements ActionListener { public void actionPerformed(ActionEvent e) { try { remoteOut.writeUTF(sendText.getText()); JOptionPane.showMessageDialog(new Frame(),"Your msg has been sent ","Confirmation",0); sendText.setText(""); } catch(IOException x) { System.out.println(x.getMessage() + " : connection to peer lost."); } } } } class chatkaro12mClientReceive extends Thread { private chatkaro12mClient chat; chatkaro12mClientReceive(chatkaro12mClient chat) { this.chat=chat; } public synchronized void run() { String s; DataInputStream remoteIn=null; try { remoteIn= new DataInputStream(chat.sock.getInputStream()); while(true) { s=remoteIn.readUTF(); chat.receivedText.setText(s); } } catch(IOException e) {

System.out.println(e.getMessage() + " : connection to peer lost."); } finally { try { if(remoteIn !=null) remoteIn.close(); } catch(IOException x) {} } } }