SlidePuzzle.java Source code

Introduction

Here is the source code for SlidePuzzle.java

Source

import java.applet.Applet;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.MediaTracker;
import java.awt.Rectangle;

/* SlidePuzzle, originally from VisualJ++ Developer's News, July 1997 */
public class SlidePuzzle extends Applet implements Runnable {
    Thread m_SlidePuzzle = null;

    private Graphics m_Graphics;

    private Image logo;

    private boolean m_fAllLoaded = false;

    private Rectangle squares[];

    private int order[];

    private int x = 1;

    private int y = 0;

    public void init() {
        //Define and populate Rectangle array
        squares = new Rectangle[9];
        squares[0] = new Rectangle(0, 0, 60, 60);
        squares[1] = new Rectangle(0, 60, 60, 60);
        squares[2] = new Rectangle(0, 120, 60, 60);
        squares[3] = new Rectangle(60, 0, 60, 60);
        squares[4] = new Rectangle(60, 60, 60, 60);
        squares[5] = new Rectangle(60, 120, 60, 60);
        squares[6] = new Rectangle(120, 0, 60, 60);
        squares[7] = new Rectangle(120, 60, 60, 60);
        squares[8] = new Rectangle(120, 120, 60, 60);

        //Define and populate int array
        order = new int[9];
        order[0] = 6;
        order[1] = 2;
        order[2] = 8;
        order[3] = 1;
        order[4] = 0;
        order[5] = 7;
        order[6] = 5;
        order[7] = 4;
        order[8] = 3;
    }

    public void paint(Graphics g) {
        if (m_fAllLoaded) {
            Rectangle r = g.getClipRect();
            g.clearRect(r.x, r.y, r.width, r.height);
            g.drawImage(logo, 0, 0, null);

        } else
            g.drawString("Loading images...", 10, 20);

    }

    public void start() {
        if (m_SlidePuzzle == null) {
            m_SlidePuzzle = new Thread(this);
            m_SlidePuzzle.start();
        }
    }

    public void stop() {
        if (m_SlidePuzzle != null) {
            m_SlidePuzzle.stop();
            m_SlidePuzzle = null;
        }
    }

    public void run() {
        if (!m_fAllLoaded) {
            m_Graphics = getGraphics();
            MediaTracker tracker = new MediaTracker(this);
            logo = getImage(getDocumentBase(), "vjlogo.gif");
            tracker.addImage(logo, 0);

            try {
                tracker.waitForAll();
                m_fAllLoaded = !tracker.isErrorAny();
            } catch (InterruptedException e) {
            }

            if (!m_fAllLoaded) {
                stop();
                m_Graphics.drawString("Error loading images!", 10, 40);
                return;
            }
        }

        //Clear the screen and draw first image
        repaint();

        //Move the squares
        while (true) {
            for (x = 1; x < 9; x++) {
                //Slow down the animation
                try {
                    Thread.sleep(350);
                } catch (InterruptedException e) {
                }

                //Move square to next location

                m_Graphics.copyArea(squares[order[x]].x, squares[order[x]].y, 60, 60,
                        squares[order[x - 1]].x - squares[order[x]].x,
                        squares[order[x - 1]].y - squares[order[x]].y);

                //Clear most recently copied square

                m_Graphics.clearRect(squares[order[x]].x, squares[order[x]].y, 60, 60);
            }

            //Repaint original graphic after two cycles
            y++;
            if (y == 2) {
                repaint();
                y = 0;
            }
        }
    }
}