Timer Application

import java.awt.Color;
import java.awt.*;
import javax.swing.Timer;
import java.awt.event.*;
 
public class Dot 
{
    private int x, y, size ;
    private Color color;
     private Timer wait, duration;
    boolean visable;
    public Dot(int x, int y, int size, Color c, ActionListener app,
                   int w, int dur) 
    {
        this.x = x;
        this.y = y;
        this.size = size;
        color = c;
        visable = false;
        wait = new Timer(w, app);
        duration = new Timer(dur, app);
        color = c;
        //color = randomColor();
    }
    public void start(){
        wait.start();
    }
    public Timer getWaitTimer(){
        return wait;
    }
    public Timer getDurationTimer(){
        return duration;
    }
 
    public boolean isVisable(){ return visable;}
    public void setVisable(boolean b){  visable = b;}
    public boolean contains (int a, int b)
    {
        if (!visable) return false;
        double r = .5 * size;
        double dx = (this.x + r) -a;
        double dy = (this.y + r) -b;
        //return (int)(Math.sqrt(dx*dx+dy*dy ));
        return (dx*dx + dy*dy <= r*r);
    }
 
    /**
     * randomInt 
     * @param min
     * @param max
     * @return a random integer from min to max (inclusive)
     */
    public int randomInt(int min, int max){
        return min + (int)(Math.random()*(max-min+1));
    }
 
    /**
     * randomColor
     * @return random Color
     */
    public Color randomColor()
    {
        return new Color( randomInt(0,255), randomInt(0,255), randomInt(0,255)); 
    }
 
    /**
     * draw
     * @param The graphics object to draw itself
     */
    public void draw(Graphics g)
    {
        if (visable) 
        {
            g.setColor(color);
            g.fillOval(x, y, size, size);
        }
    }
 
 
}

<DotTester.java> import java.awt.Color; import java.awt.Font; import java.awt.Graphics; import java.awt.event.MouseEvent; import java.awt.event.MouseListener; import java.util.ArrayList; import javax.swing.Timer; import java.awt.event.*;

import javax.swing.JFrame; import javax.swing.JPanel;

public class DotTester extends JPanel implements MouseListener, ActionListener { public static int WIDTH=800;

  public static int HEIGHT=600;
  private Font titleFont, regularFont;
  private int x,y;
  private Dot[] dots;
  private String message;
  

  public DotTester()
  {

      //initialize variables here...
      titleFont = new Font("Roman", Font.BOLD, 18);
      regularFont = new Font("Helvetica", Font.PLAIN, 12);
      x=0;
      y=0;
      message="Hit the red dot";
      dots = new Dot[3];
      dots[0] = new Dot(50,200, 50, Color.BLUE,  this,400, 350);
      dots[1] = new Dot(110,200, 50, Color.BLUE, this, 10, 490);
      dots[2] = new Dot(170,200, 50, Color.RED, this, 10, 150);
      //wait = new Timer(1000, this);
      //duration = new Timer(100, this);
      //wait.addActionListener(this);
      //duration.addActionListener(this);
      dots[0].setVisable(true);
      dots[0].start();
  }
  public static void main(String[] args) {
      DotTester app= new DotTester();
      JFrame window = new JFrame("Dot Tester");
      window.setSize(WIDTH, HEIGHT);
      window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
      window.getContentPane().add(app);

      window.getContentPane().addMouseListener(app);
      

      window.setVisible(true);

  }
  public void paintComponent(Graphics g){
      super.paintComponent(g);
      g.setColor(Color.WHITE);
      g.fillRect(0, 0, getWidth(),getHeight());
      g.setColor(Color.BLUE);
      g.setFont(titleFont);
      g.drawString("Dot Tester", 20, 20);
      g.drawString("X = "+x+"   Y = "+y, 20, 100);
      g.drawString(message, 500,200);
      g.setColor(Color.BLACK);
      g.setFont(regularFont);
      g.drawString("Click with your mouse", 20, 40);
      
      for (Dot d:dots)
          d.draw(g);

  }
  // update is a workaround to cure Windows screen flicker problem
  public void update(Graphics g){
      paint(g);
  }
  /**
   * These are the Methods needed to implement the MouseListener Interface
   */
  @Override
  public void mouseClicked(MouseEvent e) {

  }
  @Override
  public void mousePressed(MouseEvent e) {

  }
  @Override
  public void mouseReleased(MouseEvent e) {
      x=e.getX();
      y=e.getY();
      
      if (dots[2].contains(x,y) )
         message = "hit!";
      else
         message = "miss";
      repaint();
  }
  @Override
  public void mouseEntered(MouseEvent e) {

  }
  @Override
  public void mouseExited(MouseEvent e) {

  }
  public void actionPerformed(ActionEvent e) {

      for(int i=0; i< dots.length; i++)
      {
          int next = (i+1)%3;
          Timer wait = dots[i].getWaitTimer();
          Timer duration = dots[i].getDurationTimer();
      if (e.getSource()==duration){// time turn off
          duration.stop();
          dots[next].getWaitTimer().start();
          dots[i].setVisable(false);
      }
      if (e.getSource()==wait)
      { 
          wait.stop();
          duration.start();
          dots[i].setVisable(true);
          
      }
     }
      repaint();
  }

} </cose>