import java.awt.*;
import java.awt.event.*;

public class ApplicationFrame extends Frame {

    public ApplicationFrame() {
	this("ApplicationFrame v1.0");
    }

    public ApplicationFrame (String title) {
	super(title);
	createUI();
    }

    protected void createUI () {
	setSize(500, 400);
	center();

	addWindowListener (new WindowAdapter() {
		public void windowClosing (WindowEvent e) {
		    dispose();
		    System.exit(0);
		}
	    });
    }

    public void center () {
	Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
	Dimension frameSize = getSize();
	int x = (screenSize.width - frameSize.width) / 2;
	int y = (screenSize.height - frameSize.height) / 2;
	setLocation(x, y);
    }
}