RaceApplet.java Source code

Introduction

Here is the source code for RaceApplet.java

Source

/* From http://java.sun.com/docs/books/tutorial/index.html */

/*
 * Copyright (c) 2006 Sun Microsystems, Inc. All Rights Reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * -Redistribution of source code must retain the above copyright notice, this
 *  list of conditions and the following disclaimer.
 *
 * -Redistribution in binary form must reproduce the above copyright notice,
 *  this list of conditions and the following disclaimer in the documentation
 *  and/or other materials provided with the distribution.
 *
 * Neither the name of Sun Microsystems, Inc. or the names of contributors may
 * be used to endorse or promote products derived from this software without
 * specific prior written permission.
 *
 * This software is provided "AS IS," without a warranty of any kind. ALL
 * EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING
 * ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE
 * OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN MIDROSYSTEMS, INC. ("SUN")
 * AND ITS LICENSORS SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE
 * AS A RESULT OF USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS
 * DERIVATIVES. IN NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE FOR ANY LOST
 * REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL,
 * INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY
 * OF LIABILITY, ARISING OUT OF THE USE OF OR INABILITY TO USE THIS SOFTWARE,
 * EVEN IF SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
 *
 * You acknowledge that this software is not designed, licensed or intended
 * for use in the design, construction, operation or maintenance of any
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 */
import java.awt.Color;
import java.awt.Graphics;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;

import javax.swing.JApplet;
import javax.swing.JPanel;

public class RaceApplet extends JApplet implements Runnable {

    private final static int NUMRUNNERS = 2;

    private final static int SPACING = 20;

    private Runner[] runners = new Runner[NUMRUNNERS];

    private Thread updateThread = null;

    public void init() {
        String raceType = getParameter("type");
        for (int i = 0; i < NUMRUNNERS; i++) {
            runners[i] = new Runner();
            if (raceType.compareTo("unfair") == 0)
                runners[i].setPriority(i + 2);
            else
                runners[i].setPriority(2);
        }
        if (updateThread == null) {
            updateThread = new Thread(this, "Thread Race");
            updateThread.setPriority(NUMRUNNERS + 2);
        }
        addMouseListener(new MyAdapter());
        setContentPane(new AppletContentPane());
    }

    class MyAdapter extends MouseAdapter {
        public void mouseClicked(MouseEvent evt) {
            if (!updateThread.isAlive())
                updateThread.start();
            for (int i = 0; i < NUMRUNNERS; i++) {
                if (!runners[i].isAlive())
                    runners[i].start();
            }
        }
    }

    public void run() {
        Thread myThread = Thread.currentThread();
        while (updateThread == myThread) {
            repaint();
            try {
                Thread.sleep(3);
            } catch (InterruptedException e) {
            }
        }
    }

    public void stop() {
        for (int i = 0; i < NUMRUNNERS; i++) {
            if (runners[i].isAlive())
                runners[i] = null;
        }
        if (updateThread.isAlive())
            updateThread = null;
    }

    class AppletContentPane extends JPanel {
        public void paintComponent(Graphics g) {
            super.paintComponent(g);
            g.setColor(Color.white);
            g.fillRect(0, 0, getSize().width, getSize().height);
            g.setColor(Color.black);
            for (int i = 0; i < NUMRUNNERS; i++) {
                int pri = runners[i].getPriority();
                g.drawString(new Integer(pri).toString(), 0, (i + 1) * SPACING);
            }
            for (int i = 0; i < NUMRUNNERS; i++) {
                g.drawLine(SPACING, (i + 1) * SPACING, SPACING + (runners[i].tick) / 23000, (i + 1) * SPACING);
            }
        }
    }
}

class Runner extends Thread {
    public int tick = 1;

    public void run() {
        while (tick < 10000000)
            tick++;
    }
}