www.pudn.com > src.rar > FishIcon.java

/* 
* Copyright (c) 1996, 1997 Bill Venners. All Rights Reserved. 
* 
* This Java source file is part of the Interactive Illustrations Web 
* Site, which is delivered in the applets directory of the CD-ROM 
* that accompanies the book "Inside the Java Virtual Machine" by Bill 
* Venners, published by McGraw-Hill, 1997,ISBN: 0-07-913248-0. This 
* source file is provided for evaluation purposes only, but you can 
* redistribute it under certain conditions, described in the full 
* copyright notice below. 
* 
* Full Copyright Notice: 
* 
* All the web pages and Java applets delivered in the applets 
* directory of the CD-ROM, consisting of ".html," ".gif," ".class," 
* and ".java" files, are copyrighted (c) 1996, 1997 by Bill 
* Venners, and all rights are reserved.  This material may be copied 
* and placed on any commercial or non-commercial web server on any 
* network (including the internet) provided that the following 
* guidelines are followed: 
* 
* a. All the web pages and Java Applets (".html," ".gif," ".class," 
* and ".java" files), including the source code, that are delivered 
* in the applets directory of the CD-ROM that 
* accompanies the book must be published together on the same web 
* site. 
* 
* b. All the web pages and Java Applets (".html," ".gif," ".class," 
* and ".java" files) must be published "as is" and may not be altered 
* in any way. 
* 
* c. All use and access to this web site must be free, and no fees 
* can be charged to view these materials, unless express written 
* permission is obtained from Bill Venners. 
* 
* d. The web pages and Java Applets may not be distributed on any 
* media, other than a web server on a network, and may not accompany 
* any book or publication. 
* 
* BILL VENNERS MAKES NO REPRESENTATIONS OR WARRANTIES ABOUT THE 
* SUITABILITY OF THE SOFTWARE, EITHER EXPRESS OR IMPLIED, INCLUDING 
* BUT NOT LIMITED TO THE IMPLIED WARRANTIES OF MERCHANTABILITY, 
* FITNESS FOR PARTICULAR PURPOSE, OR NON-INFRINGEMENT.  BILL VENNERS 
* SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY A LICENSEE AS A 
* RESULT OF USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS 
* DERIVATIVES. 
*/ 
import java.awt.Graphics; 
import java.awt.Point; 
import java.awt.Dimension; 
import java.awt.Polygon; 
import java.awt.Color; 
 
// Fish Icon 
// 
// topTail   frontTail 
//      |\       |       /\ 
//      |  \     |     /    \ 
//       \   \   |   /        \ 
//         \   \   /        o   \ 
// backTail  >--><               > 
//         /   /   \            / 
//       /   /       \        / 
//       | /           \    / 
//       |/              \/ 
// bottomTail 
// 
/** 
* This class represents each fish icon that appears on 
* the user interface. It is an abstract class that is 
* subclass by BigRedFishIcon, MediumBlueFishIcon, and 
* LittleYellowFishIcon, which initialize many of the 
* protected instance variables and define the abstract 
* method getFishColor(). This class takes care of drawing 
* the fish. For each fish on the heap, the object handle 
* data contains a reference to an instance of this class, 
* which serves as the "class data" for the objects on 
* this simulated heap. 
* 
* @author  Bill Venners 
*/ 
abstract class FishIcon { 
 
    protected Point topTail; 
    protected Point backTail; 
    protected Point bottomTail; 
    protected Point frontTail; 
    protected Polygon staticTail = new Polygon(); 
 
    protected final int swimmingTailPositionCount = 10; 
    protected Polygon[] swimmingTail = new Polygon[swimmingTailPositionCount]; 
    protected int currentSwimmingTailPos = 0; 
    protected int holdTailPositionCounter = 0; 
    protected int maxPaintsToHoldTailInOnePosition; 
 
    protected Point ovalPos; 
    protected Dimension ovalDim; 
 
    protected Point eyePos; 
    protected Dimension eyeDim; 
 
    protected Point fishPosition; 
    protected boolean fishHasBeenInitiallyPositioned; 
 
    protected boolean fishIsSwimming; 
 
    protected Color fishColor; 
 
    public void moveFish(int x, int y) { 
 
        fishHasBeenInitiallyPositioned = true; 
        fishPosition.x = x; 
        fishPosition.y = y; 
    } 
 
    public int getFishHeight() { 
        return bottomTail.y; 
    } 
 
    public int getFishWidth() { 
        return frontTail.x + ovalDim.width; 
    } 
 
    public Point getFishPosition() { 
        return new Point(fishPosition.x, fishPosition.y); 
    } 
 
    public boolean getFishHasBeenInitiallyPositioned() { 
        return fishHasBeenInitiallyPositioned; 
    } 
 
    public Point getFishNosePosition() { 
        return new Point(fishPosition.x + frontTail.x + ovalDim.width, 
            fishPosition.y + (ovalDim.height / 2)); 
    } 
 
    public abstract Color getFishColor(); 
 
    public void paint(Graphics g) { 
        paintWithSpecialColors(g, fishColor, Color.black); 
    } 
 
    public void paintWithSpecialColors(Graphics g, Color bodyColor, Color eyeColor) { 
 
        g.translate(fishPosition.x, fishPosition.y); 
 
        g.setColor(bodyColor); 
        if (fishIsSwimming) { 
            if (holdTailPositionCounter < maxPaintsToHoldTailInOnePosition) { 
                ++holdTailPositionCounter; 
            } 
            else { 
                holdTailPositionCounter = 0; 
                ++currentSwimmingTailPos; 
                if (currentSwimmingTailPos == swimmingTailPositionCount) { 
                    currentSwimmingTailPos = 0; 
                } 
            } 
            g.fillPolygon(swimmingTail[currentSwimmingTailPos]); 
        } 
        else { 
            g.fillPolygon(staticTail); 
        } 
 
        g.fillOval(ovalPos.x, ovalPos.y, ovalDim.width, ovalDim.height); 
 
        g.setColor(eyeColor); 
        g.fillOval(eyePos.x, eyePos.y, eyeDim.width, eyeDim.height); 
 
        g.translate(0 - fishPosition.x, 0 - fishPosition.y); 
    } 
 
    public void drawFishOutline(Graphics g, int x, int y) { 
 
        g.translate(x, y); 
 
        g.drawPolygon(staticTail); 
 
        g.drawOval(ovalPos.x, ovalPos.y, ovalDim.width, ovalDim.height); 
 
        g.drawOval(eyePos.x, eyePos.y, eyeDim.width, eyeDim.height); 
 
        g.translate(0 - x, 0 - y); 
    } 
}