LinuxQuestions.org - problem in java web server

I make a simple java web server.It works well,but now i want to stop it by using stop button.But it don't works correctly.Here is my code...

import java.awt.event.ActionListener;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import javax.swing.*;
import java.net.Socket;
import java.net.ServerSocket;
import java.net.InetAddress;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.IOException;
import java.io.File;

class HttpServer
{
/* WEB_ROOT is the directory where our HTML and other files reside.
*/
public static final String WEB_ROOT =
System.getProperty("user.dir") + File.separator + "content";

// shutdown command
public static final String SHUTDOWN_COMMAND = "/SHUTDOWN";

// the shutdown command received
public boolean shutdown = false;
ServerSocket serverSocket;
Socket socket;
InputStream input;
OutputStream output;

public void await() {
serverSocket = null;
int port = 8080;
try {
serverSocket = new ServerSocket(port, 1, InetAddress.getByName("127.0.0.1"));
}
catch (IOException e) {
e.printStackTrace();
System.exit(1);
}

// Loop waiting for a request
while (!shutdown)
{
try {
socket = serverSocket.accept();
input = socket.getInputStream();
output = socket.getOutputStream();

// create Request object and parse
Request request = new Request(input);
request.parse();

// create Response object
Response response = new Response(output);
response.setRequest(request);
response.sendStaticResource();

// Close the socket
socket.close();

}
catch (Exception e) {
e.printStackTrace();
continue;
}
}

}

public void closeConnection()
{
String errorMessage = "Connection terminating";
try {
output.write(errorMessage.getBytes());
}
catch (IOException e) {
e.printStackTrace();
}
output=null;
input=null;
socket=null;

}
}

class button extends JFrame
{
private JButton start;
private JButton stop;

public button()
{
super("Testing buttons");
setLayout(new FlowLayout());

start=new JButton("Start");
add(start);

stop=new JButton("Stop");
add(stop);

start.addActionListener( new ActionListener()
{
public void actionPerformed(ActionEvent ae)
{
HttpServer server = new HttpServer();
server.await();
start.setEnabled(false);
stop.setEnabled(true);
}
});

stop.addActionListener( new ActionListener()
{
public void actionPerformed(ActionEvent ae1)
{
HttpServer server = new HttpServer();
server.closeConnection();
stop.setEnabled(false);
start.setEnabled(true);
}
});
}
}

public class Server {
public static void main(String args[])
{
button b=new button();
b.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
b.setSize(300,200);
b.setVisible(true);
}
}

Anyone can help me..?
Thanks for any answer.