Question

Problem descriptions:

In this mini project, you are to develop a chat program for peer-to-peer communications. The techniques involved in this mini project include multithreading, client-server application using sockets, and graphical user interface (GUI).

Part A. In this part your implementation should include a client-server chatting functionality with one server and one client, where the client initiates the communication and the server responds. Show below is an example of a simple GUI for communications. You can fine-tune the GUI to include more features.

Part B. Modify your program developed in Part A to make it a peer-to-peer chat program so that either side can initiate the communication.

Answer 1

Hi,

This client server application is basic GUI based application..client or server both can initiate the chat.

How to run Client-Server

1.First compile both client and server programs.

2. Start server program then

3.Start client program

enjoy the chatting!

Chat Client:

import java.awt.*;
import java.awt.event.*;

import java.io.*;
import java.net.*;
/**
 App client which will connection to server.
 */
public class ChatClient extends Frame implements ActionListener,Runnable
{
 //Declarations
 Button b;
 TextField tf;
 TextArea ta;
 Socket s;
 PrintWriter pw;
 BufferedReader br;
 Thread th;
 
 public ChatClient()
 {
  Frame f=new Frame("Client Window");//Frame for Client
  f.setLayout(new FlowLayout());//set layout
  f.setBackground(Color.blue);//set background color of the Frame
  b=new Button("Send");//Send Button
  //b=setBackground(Color.white);

  b.addActionListener(this);//Add action listener to send button.
  f.addWindowListener(new W1());//add Window Listener to the Frame
  tf=new TextField(15);
  ta=new TextArea(12,20);
  ta.setBackground(Color.white);
  f.add(tf);//Add TextField to the frame
  f.add(b);//Add send Button to the frame
  f.add(ta);//Add TextArea to the frame
  try{
   s=new Socket(InetAddress.getLocalHost(),12000);//Socket for client
   //below line reads input from InputStreamReader
   br=new BufferedReader(new InputStreamReader(s.getInputStream()));
   //below line writes output to OutPutStream
   pw=new PrintWriter(s.getOutputStream(),true);
  }catch(Exception e)  
  {
  }
  th=new Thread(this);//start a new thread
  th.setDaemon(true);//set the thread as demon
  th.start();
  setFont(new Font("Arial",Font.BOLD,20));
  f.setSize(300,300);//set the size
  f.setVisible(true);
  f.setLocation(100,300);//set the location
  f.validate();
 }
 //method required to close the Frame on clicking "X" icon.
 private class W1 extends WindowAdapter
 {
  public void windowClosing(WindowEvent we)
  {
   System.exit(0);
  }
 }
 //This method will called after clicking on Send button.
 public void actionPerformed(ActionEvent ae)
 {
  pw.println(tf.getText());//write the value of textfield into PrintWriter
  tf.setText("");//clean the textfield
 }
 //Thread running as a process in background
 public void run()
 {
  while(true)
  {
   try{
    ta.append(br.readLine()+"\n");//Append to TextArea
   }catch(Exception e) {}
  }
 }
 //Main method
 public static void main(String args[])
 {
  //Instantiate AppClient class
   ChatClient client = new ChatClient();
 }
}

:

Chat Server:

import java.awt.*;
import java.awt.event.*;
import java.io.*;
import java.net.*;

// chat server will handle request.
public class ChatServer extends Frame implements ActionListener,Runnable
{
 //Declarations
 Button b1;
 TextField tf;
 TextArea ta;
 ServerSocket ss;
 Socket s;
 PrintWriter pw;
 BufferedReader br;
 Thread th;
 
 public ChatServer()
 {
  Frame f=new Frame("Server Window");//Frame for Server
  f.setLayout(new FlowLayout());//set layout
  f.setBackground(Color.blue);//set background color of the Frame
  b1=new Button("Send");//Send Button
  //b1.setBackground(Color.red);
  b1.addActionListener(this);//Add action listener to send button.
  tf=new TextField(15);
  ta=new TextArea(12,20);
  ta.setBackground(Color.white);
  f.addWindowListener(new W1());//add Window Listener to the Frame
  f.add(tf);//Add TextField to the frame
  f.add(b1);//Add send Button to the frame
  f.add(ta);//Add TextArea to the framered
  try{
   ss=new ServerSocket(12000);//Socket for server
   s=ss.accept();//accepts request from client
   System.out.println(s);
   //below line reads input from InputStreamReader
   br=new BufferedReader(new InputStreamReader(s.getInputStream()));
   //below line writes output to OutPutStream
   pw=new PrintWriter(s.getOutputStream(),true);
  }catch(Exception e)
  {
  }
  th=new Thread(this);//start a new thread
  th.setDaemon(true);//set the thread as demon
  th.start();
  setFont(new Font("Arial",Font.BOLD,20));
  f.setSize(300,300);//set the size
  f.setLocation(300,300);//set the location
  f.setVisible(true);
  f.validate();
 }
 //method required to close the Frame on clicking "X" icon.
 private class W1 extends WindowAdapter
 {
  public void windowClosing(WindowEvent we) 
  {
   System.exit(0);
  }
 }
 //This method will called after clicking on Send button.
 public void actionPerformed(ActionEvent ae)
 {
  pw.println(tf.getText());//write the value of textfield into PrintWriter
  tf.setText("");//clean the textfield
 }
 //Thread running as a process in background
 public void run()
 {
  while(true)
  {
   try{
    String s=br.readLine();//reads the input from textfield
    ta.append(s+"\n");//Append to TextArea
   }catch(Exception e)
   {
   }
  } 
 }
 //Main method
 public static void main(String args[]) 
 {
  //Instantiate AppServer class
  ChatServer server = new ChatServer();
 }
} 

Output:

Client Window - - Send Micros (c) 2€ 1°C:\Use Hi I'm doing well.How are yo This is amazing chat app cs. Command Prompt - java AppServer erved. 04 03 1990 05 false false C:\USE E: 2 Server Window C:\>e: E: Send E:\>CO E: ava Hi How are you doing? ya very nice! E: Soc alport=12000] E:\ja E:\ja dae: \ja E: \java programs\chatApp>javac AppClient.java E:\java programs\chatApp>java AppClient E: E: E: E: E: E: E: E: cl ope nal or external command, E: ava E:\java programs\chatApp>java AppServer Socket[addr=/192.168.43.254, port=64834, localport=12000] 33 private class wi extends WindowAdapt 54 { 55 public void windorisine indosent we

Thanks