import javax.swing.JFrame;
import javax.swing.JButton;

public class FirstSwingDemo
{
    public static final int WIDTH = 300; 
    public static final int HEIGHT = 200;

    public static void main(String[] args)
    {
        JFrame firstWindow = new JFrame( );
        firstWindow.setSize(WIDTH, HEIGHT);

        firstWindow.setDefaultCloseOperation(
                              JFrame.DO_NOTHING_ON_CLOSE);

        JButton endButton = new JButton("Click to end program.");
        EndingListener buttonEar = new EndingListener( );
        endButton.addActionListener(buttonEar);
        firstWindow.getContentPane( ).add(endButton);

        firstWindow.setVisible(true);
    }
}