Add button functionality to the resulting GUI of number 2 above.When the button is clicked,the title of the window changes to "Modified First Window".

Additional code for button functionality appears below in bold text.
import javax.swing.JFrame;
import javax.swing.JButton;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
public class FirstGui
{
public static final int WIDTH = 300;
public static final int HEIGHT = 300;
public static void mainString args[])
{
final JFrame window = new JFrame);
window.setSizeWIDTH,HEIGHT);
JButton btnClick = new JButton"Click Me");
window.getContentPane).addbtnClick);
btnClick.addActionListenernew ActionListener)
{
public void actionPerformedActionEvent e)
{
window.setTitle"Modified First Window");
}
});
window.setTitle"First Window");
window.setDefaultCloseOperation JFrame.EXIT_ON_CLOSE );
window.setVisibletrue);
}
}