server.java

Small chat on Java. works good

package javaapplication2;
import java.io.*;
import java.net.*;
public class Server extends javax.swing.JFrame {

    public Server()
    {
            initComponents();
    }
    public Server(int port) {
        initComponents();
        
    }
   
   
    // <editor-fold defaultstate="collapsed" desc="Generated Code">//GEN-BEGIN:initComponents
    private void initComponents() {

        jLabel1 = new javax.swing.JLabel();
        Port = new javax.swing.JTextField();
        Start = new javax.swing.JButton();

        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);

        jLabel1.setText("Port");

        Port.setText("8111");

        Start.setText("Start");
        Start.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                StartActionPerformed(evt);
            }
        });

        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
        getContentPane().setLayout(layout);
        layout.setHorizontalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addContainerGap()
                .addComponent(jLabel1)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addComponent(Port, javax.swing.GroupLayout.PREFERRED_SIZE, 34, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addComponent(Start)
                .addContainerGap(25, Short.MAX_VALUE))
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addContainerGap()
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                    .addComponent(jLabel1)
                    .addComponent(Start)
                    .addComponent(Port, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
                .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
        );

        pack();
    }// </editor-fold>//GEN-END:initComponents

    private void StartActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_StartActionPerformed
       Start.setEnabled(false);
        Thread c= new StartServer(Integer.parseInt(Port.getText()));
        c.start();    
    }//GEN-LAST:event_StartActionPerformed
    
   
    public static void main(String args[]) {
        java.awt.EventQueue.invokeLater(new Runnable() {
            public void run() {
                new Server().setVisible(true);
            }
        });
    }
    
    // Variables declaration - do not modify//GEN-BEGIN:variables
    private javax.swing.JTextField Port;
    private javax.swing.JButton Start;
    private javax.swing.JLabel jLabel1;
    // End of variables declaration//GEN-END:variables
    
}



//********************************************************************
class StartServer extends Thread
{

 static Socket clientSocket = null;
    static PrintStream os = null;
    static DataInputStream is = null;
    static BufferedReader inputLine = null;
    static boolean closed = false;
    int port_number;
    static  ServerSocket serverSocket = null;

    static  clientThread t[] = new clientThread[10];           
    public StartServer(int port) 
    {
        port_number=port;
    
    }
    
    public void run()
    {
    
       try {
	    serverSocket = new ServerSocket(port_number);
        }
        catch (IOException e)
	    {System.out.println(e);}
	
	while(true){
	    try {
		clientSocket = serverSocket.accept();
		for(int i=0; i<=9; i++){
		    if(t[i]==null){
			    (t[i] = new clientThread(clientSocket,t)).start();
			    break;
			}
		}
	    }
	    catch (IOException e) {
		System.out.println(e);}
	}
    
    
    }
        	
	
}

//********************************************************************
class clientThread extends Thread{ 
    DataInputStream is = null;
    PrintStream os = null;
    Socket clientSocket = null;       
    clientThread t[]; 
    
    public clientThread(Socket clientSocket, clientThread[] t){
	this.clientSocket=clientSocket;
        	this.t=t;
    }
    
    public void run() 
    {
	String line;
        	String name;
	try{
	    is = new DataInputStream(clientSocket.getInputStream());
	    os = new PrintStream(clientSocket.getOutputStream());
	    os.println("Enter your name.");
	    name = is.readLine();
	    os.println("Welcome "+name+" to our chat room.\nEnter /quit to leave room"); 
	    for(int i=0; i<=9; i++)
		if (t[i]!=null && t[i]!=this)  
		    t[i].os.println("*** A new user "+name+" entered the chat room !!! ***" );
	    while (true) {
		line = is.readLine();
                		if(line.startsWith("/quit")) break; 
		for(int i=0; i<=9; i++)
		    if (t[i]!=null)  t[i].os.println("<"+name+"> "+line); 
	    }
	    for(int i=0; i<=9; i++)
		if (t[i]!=null && t[i]!=this)  
		    t[i].os.println("*** The user "+name+" is leaving the chat room !!! ***" );
	    
	    os.println("*** Bye "+name+" ***"); 

	    for(int i=0; i<=9; i++)
		if (t[i]==this) t[i]=null;  
		
	    is.close();
	    os.close();
	    clientSocket.close();
	}
	catch(IOException e){};
    }
}