/** Synchronized example based on pg 266 of
    'Java Certification Exam Guide for Programmers and Developers'  
    by Barry Boone, McGraw-Hill, 1997
    Synchronized display of number of times the mouse has been clicked 
    Modified to remove deprecated methods
 */
 
 import java.awt.*;
 import java.awt.event.*;
 import java.applet.*;
 
 public class ClickApplet extends Applet implements MouseListener{
    boolean clicked;
    int counter;
    
    public void init() {
        
        // add a mouse handler to the applet        
        addMouseListener(this);
        
        // add two ClickCanvas components                
        add(new ClickCanvas(this));
        add(new ClickCanvas(this));

    }

    // handle mouse clicked event    
    public void mouseClicked(MouseEvent e) {
       synchronized (this) {
        clicked = true;
        notifyAll();
       }                        
        counter++;
        System.out.println("Count: " + counter);
        Thread.currentThread().yield();
        clicked = false;
    }
    
    // stub methods
    public void mouseEntered(MouseEvent e) {}
    public void mouseExited(MouseEvent e) {}
    public void mousePressed(MouseEvent e) {}
    public void mouseReleased(MouseEvent e) {}          
            
} // end of ClickApplet

class ClickCanvas extends Canvas implements Runnable {
    ClickApplet applet;
        
    ClickCanvas(ClickApplet applet) {
        this.applet = applet;
        setSize(30,30);                     // original resize() deprecated
        new Thread(this).start();
    } 
    
    // override run() in Runnable
    public void run() {
        while(true) {
            synchronized(applet) {
                while( !applet.clicked) {
                    try {
                        applet.wait();
                    } catch(InterruptedException e) {
                    }
                } // end of while
            } // end of synchronized block
            repaint();
            
        } // end of while
    } // end of run()
    
    public void paint(Graphics g) {
        g.drawString(new Integer(applet.counter).toString(), 10,20);
    }
         
} // end of ClickCanvas