Timer Application

Dot.java

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();
    }
 
 
}