import java.applet.Applet;
import java.awt.*;
import java.awt.event.*;
import java.util.Vector;

/** An applet that draws a small circle where you click.
 *
 *  Taken from Core Web Programming from 
 *  Prentice Hall and Sun Microsystems Press,
 *  http://www.corewebprogramming.com/.
 *  © 2001 Marty Hall and Larry Brown;
 *  may be freely used or adapted.
 */

public class DrawCircles extends Applet {

  private Vector circles;

  /** When you click the mouse, create a SimpleCircle,
   *  put it in the Vector, and tell the system
   *  to repaint (which calls update, which clears
   *  the screen and calls paint).
   */

  private class CircleDrawer extends MouseAdapter {
    public void mousePressed(MouseEvent event) {
      circles.addElement(
         new SimpleCircle(event.getX(),event.getY(),25));
      repaint();
    }
  }

  public void init() {
    circles = new Vector();
    addMouseListener(new CircleDrawer());
    setBackground(Color.white);
  }

  /** This loops down the available SimpleCircle objects,
   *  drawing each one.
   */

  public void paint(Graphics g) {
    SimpleCircle circle;
    for(int i=0; i<circles.size(); i++) {
      circle = (SimpleCircle)circles.elementAt(i);
      circle.draw(g);
    }
  }
}