ActionListener,FocusListener,WindowListener

import java.awt.event.*;
import java.awt.*;
import javax.swing.*;
public class EvtCk extends JFrame implements WindowListener
{
JButton b;
JTextField text;
frame f;
public EvtCk()
{
super("Events");
setVisible(true);
setSize(300,300);
getContentPane().setLayout(new FlowLayout());
b=new JButton("OK");
text=new JTextField(10);
getContentPane().add(b);
getContentPane().add(text);
ButtonListener blisten=new ButtonListener();
b.addActionListener(blisten);
text.addFocusListener(blisten);
this.addWindowListener(this);
}
public void windowClosing(WindowEvent win)
{
System.out.println("Window Closing");//-----

System.exit(0);
}
public void windowDeactivated(WindowEvent win)
{
System.out.println("Window Deactivated");//----
}
public void windowIconified(WindowEvent win)
{
System.out.println("Window Iconified");//-----
}
public void windowDeiconified(WindowEvent win)
{
System.out.println("Window Deiconified");//---
}
public void windowActivated(WindowEvent win)
{
System.out.println("Window Activated");//-----

}
public void windowClosed(WindowEvent win)
{
f=new frame();
f.show();
System.out.println("Window Closed");
}

public void windowOpened(WindowEvent win)
{
System.out.println("Window Opened");

}
class ButtonListener implements ActionListener,FocusListener
{
public void actionPerformed(ActionEvent e)
{
String msg=e.getActionCommand();
if(msg=="OK")
System.out.println("Button Clicked");
}
public void focusGained(FocusEvent f)
{
System.out.println("Text got focus");
}
public void focusLost(FocusEvent f)
{
text.requestFocus();
System.out.println("Text lost focus");
}
}
public static void main(String args[])
{
new EvtCk();
}
}
class frame extends JFrame
{
frame()
{
setSize(200,300);
}
}