Client Side Application

For creating the Client side application firstly creates the login frame it consist one textfield and the login button. After hitting the login button it shows the next frame that Client Frame and it consist one textfield for writing the message and one send button for sending it. And two list boxes, one is for showing the all messages and another list box is use to show the all user names. This frame has one more button that is Logout button for terminating the chat.

For running the whole Client operation we can run the Login file (Login.java). It can directly call Client file (MyClient.java).

Here is the code of Login.java file :


/****************************************************************

*  Version    :  1.0

*  Date    :  02/03/2007

*  

*  Description

*  This is a Login frame of client side application in chat System.

*  It is used to just take the user name 

*  

*  Remarks

*  Before running the Login application make sure the server is 

*  running.

*  If server is running then only you can execute your application.

******************************************************************/



import javax.swing.*;

import java.awt.*;

import java.awt.event.*;

import java.io.*;

import java.util.*;



// Login class which takes a user name and passed it to client class

public class Login implements ActionListener{

  JFrame frame1;

  JTextField tf;

  JButton button;

  JLabel heading;

  JLabel label;

  public static void main(String[] args){

    new Login();

  }

  public Login(){

    frame1 = new JFrame("Login Page");

    tf=new JTextField();

    button=new JButton("Login");

    heading=new JLabel("Chat Server");

    heading.setFont(new Font("Impact", Font.BOLD,40));

    label=new JLabel("Enter you Login Name");

    label.setFont(new Font("Serif", Font.PLAIN, 24));

    JPanel panel = new JPanel();

    button.addActionListener(this);

    panel.add(heading);panel.add(tf);panel.add(label);

    panel.add(button);

    heading.setBounds(30,20,280,80);

    label.setBounds(20,100,250,60);

    tf.setBounds(50,150,150,30);

    button.setBounds(70,200,90,30);

    frame1.add(panel);

    panel.setLayout(null);

    frame1.setSize(300, 300);

      frame1.setVisible(true);

    frame1.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

  }

  // pass the user name to MyClient class

  public void actionPerformed(ActionEvent e){

    String name="";

    try{

      name=tf.getText();

      frame1.dispose();

      MyClient mc=new MyClient(name);

    }catch (IOException te){}

  }

}

Output of the code is :

The Client side application follows these steps :

In the client sides firstly creates a new socket and specifies the address and port of the server and establish the connection with the Server.
Socket s=new Socket("localhost",1004);

Note - Instead of "localhost" you have to write the server IP address or computer name.

After that client makes a new thread and DataInputStream, ObjectInputStream and DataOutputStream for sending the user name and retrieving the list of all users and add the all user name in its list box through iterator.
        DataOutputStream dout=new DataOutputStream(s.getOutputStream());
        dout.writeUTF(name);
        DataInputStream din1=new DataInputStream(s.getInputStream());
        ObjectInputStream obj=new ObjectInputStream(din1);
        ArrayList alname=new ArrayList();
        Alname=(ArrayList)obj.readObject();
        String lname;
        Iterator i1=alname.iterator();
        while(i1.hasNext()){
        lname=(String)i1.next();
        model1.addElement(lname);
        }

Note � model1 is the object of DefaultListModel that is used to add the element in JList Box.

Now we make one new thread for sending and receiving the messages from the server. It does this task by using DataInputStream and DataOutputStream.
        dout.writeUTF(str); // for sending the messages
        str1=din.readUTF(); // receiving the messages
        model.addElement(str1) // add these messages to JList Box

When the client is logged out it sends its name and message �User_Name has Logged out� and terminate the chatting
dout.writeUTF(name+" has Logged out");
dlout.writeUTF(name);

Here is the code of Client Side application :


/****************************************************************

*  Version    :  1.0

*  Date       :  02/03/2007

*  

*  Description

*  This is a client side of chat application.

*  This application is used to sending and receiving the messages

*  and in this we can maintain the list of all online users

*  

*  Remarks

*  Before running the client application make sure the server is 

*  running.If server is running then only you can execute your

*  application.

******************************************************************/

import javax.swing.*;

import java.awt.*;

import java.awt.event.*;

import java.io.*;

import java.net.*;

import java.util.ArrayList;

import java.util.Iterator;



//create the GUI of the client side

public class MyClient extends WindowAdapter implements ActionListener{

  JFrame frame;

  JList list;

  JList list1;

  JTextField tf;

  DefaultListModel model;

  DefaultListModel model1;

  JButton button;

  JButton lout;

  JScrollPane scrollpane;

  JScrollPane scrollpane1;

  JLabel label;

  Socket s,s1,s2;

  DataInputStream din;

  DataOutputStream dout;

  DataOutputStream dlout;

  DataOutputStream dout1;

  DataInputStream din1;

  String name;

  

  MyClient(String name)throws IOException{

    frame = new JFrame("Client Side");

    tf=new JTextField();

    model=new DefaultListModel();

    model1=new DefaultListModel();

    label=new JLabel("Message");

    list=new JList(model);

    list1=new JList(model1);

    button=new JButton("Send");

    lout=new JButton("Logout");

    scrollpane=new JScrollPane(list);

    scrollpane1=new JScrollPane(list1);

    JPanel panel = new JPanel();

    button.addActionListener(this);

    lout.addActionListener(this);

    panel.add(tf);panel.add(button);panel.add(scrollpane);

    panel.add(label);panel.add(lout);

    panel.add(scrollpane1);

    scrollpane.setBounds(10,20,180,150);

    scrollpane1.setBounds(250,20,100,150);

    label.setBounds(20,180,80,30);

    tf.setBounds(100,180,140,30);

    button.setBounds(260,180,90,30);

    lout.setBounds(260,230,90,30);

    frame.add(panel);

    panel.setLayout(null);

    frame.setSize(400, 400);

       frame.setVisible(true);

    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    this.name=name;

    frame.addWindowListener(this);

    s=new Socket("localhost",1004);  //creates a socket object

    s1=new Socket("localhost",1004);

    s2=new Socket("localhost",1004);

      //create inputstream for a particular socket

    din=new DataInputStream(s.getInputStream());

    //create outputstream

    dout=new DataOutputStream(s.getOutputStream());

    //sending a message for login

    dout.writeUTF(name+" has Logged in");  

    dlout=new DataOutputStream(s1.getOutputStream());

    dout1=new DataOutputStream(s2.getOutputStream());

    din1=new DataInputStream(s2.getInputStream());



// creating a thread for maintaning the list of user name

    My1 m1=new My1(dout1,model1,name,din1);

    Thread t1=new Thread(m1);

    t1.start();      

  //creating a thread for receiving a messages

    My m=new My(din,model);

    Thread t=new Thread(m);

    t.start();

    }

  public void actionPerformed(ActionEvent e){

    // sending the messages

    if(e.getSource()==button){  

      String str="";

      str=tf.getText();

      tf.setText("");

      str=name+": > "+str;

      try{

      dout.writeUTF(str);

      System.out.println(str);

      dout.flush();

      }catch(IOException ae){System.out.println(ae);}

    }

    // client logout

    if (e.getSource()==lout){

      frame.dispose();

      try{

         //sending the message for logout

      dout.writeUTF(name+" has Logged out");

      dlout.writeUTF(name);

      dlout.flush();

      Thread.currentThread().sleep(1000);

      System.exit(1);

      }catch(Exception oe){}

    }

  }

  public void windowClosing(WindowEvent w){

    try{

      dlout.writeUTF(name);

      dlout.flush();  

      Thread.currentThread().sleep(1000);

      System.exit(1);

      }catch(Exception oe){}

    }

}



// class is used to maintaning the list of user name

class My1 implements Runnable{

  DataOutputStream dout1;

  DefaultListModel model1;  

  DataInputStream din1;

  String name,lname;

  ArrayList alname=new ArrayList(); //stores the list of user names

  ObjectInputStream obj; // read the list of user names

  int i=0;

  My1(DataOutputStream dout1,DefaultListModel model1,

         String name,DataInputStream din1){

    this.dout1=dout1;

    this.model1=model1;

    this.name=name;

    this.din1=din1;

  }

  public void run(){

    try{

    dout1.writeUTF(name);  // write the user name in output stream

    while(true){

      obj=new ObjectInputStream(din1);

      //read the list of user names

      alname=(ArrayList)obj.readObject(); 

      if(i>0)

      model1.clear(); 

      Iterator i1=alname.iterator();

      System.out.println(alname);

      while(i1.hasNext()){

        lname=(String)i1.next();

        i++;

         //add the user names in list box

        model1.addElement(lname);

        }

      }

    }catch(Exception oe){}

  }

}

//class is used to received the messages

class My implements Runnable{

  DataInputStream din;

  DefaultListModel model;

  My(DataInputStream din, DefaultListModel model){

    this.din=din;

    this.model=model;

  }

  public void run(){

    String str1="";

    while(true){

      try{

        str1=din.readUTF(); // receive the message

        // add the message in list box

        model.addElement(str1);

      }catch(Exception e){}

    }

  }

}

Output of the Client Side Application is