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

/* 
 * Copyright (c) 2005 Your Corporation. All Rights Reserved. 
 */ 
import java.awt.*; 
import java.applet.*; 
 
/** 
* This applet simulates a compacting, mark-and-sweep 
* garbage-collected heap inside a Java Virtual Machine. 
* 
* @author  Bill Venners 
*/ 
/* 
 
 
*/ 
public class HeapOfFish extends Applet { 
 
    private GCHeap gcHeap = new GCHeap(15, 50); 
    private LocalVariables localVars = new LocalVariables(); 
 
    private HeapOfFishControlPanel controlPanel = new HeapOfFishControlPanel(); 
    private HeapOfFishCanvases canvases = new HeapOfFishCanvases(gcHeap, localVars, controlPanel.getTextArea()); 
    private String currentHeapOfFishMode = HeapOfFishStrings.swim; 
 
    public void init() { 
 
        super.init(); 
        setBackground(Color.cyan); 
 
        setLayout(new BorderLayout(5, 5)); 
        add("North", new ColoredLabel("HEAP OF FISH", Label.CENTER, Color.white)); 
        add("South", controlPanel); 
        add("Center", canvases); 
    } 
 
    public void start() { 
        canvases.start(); 
    } 
 
    public void stop() { 
        canvases.stop(); 
    } 
 
    public Insets insets() { 
        return new Insets(5, 5, 5, 5); 
    } 
 
    public boolean action(Event evt, Object arg) { 
        if (evt.target instanceof Checkbox) { 
            Checkbox cb = (Checkbox) evt.target; 
            String cbname = cb.getLabel(); 
            if (cbname.equals(HeapOfFishStrings.allocateFish)) { 
                if (!currentHeapOfFishMode.equals(HeapOfFishStrings.allocateFish)) { 
                    controlPanel.getTextArea().setText(HeapOfFishStrings.allocateFishInstructions); 
                    canvases.setMode(HeapOfFishStrings.allocateFish); 
                } 
            } 
            else if (cbname.equals(HeapOfFishStrings.assignReferences)) { 
                if (!currentHeapOfFishMode.equals(HeapOfFishStrings.assignReferences)) { 
                    canvases.setMode(HeapOfFishStrings.assignReferences); 
                } 
            } 
            else if (cbname.equals(HeapOfFishStrings.garbageCollect)) { 
                if (!currentHeapOfFishMode.equals(HeapOfFishStrings.garbageCollect)) { 
                    canvases.setMode(HeapOfFishStrings.garbageCollect); 
                } 
            } 
            else if (cbname.equals(HeapOfFishStrings.compactHeap)) { 
                if (!currentHeapOfFishMode.equals(HeapOfFishStrings.compactHeap)) { 
                    controlPanel.getTextArea().setText(HeapOfFishStrings.compactHeapInstructions); 
                    canvases.setMode(HeapOfFishStrings.compactHeap); 
                } 
            } 
            else if (cbname.equals(HeapOfFishStrings.swim)) { 
                if (!currentHeapOfFishMode.equals(HeapOfFishStrings.swim)) { 
                    controlPanel.getTextArea().setText(""); 
                    canvases.setMode(HeapOfFishStrings.swim); 
                } 
            } 
            currentHeapOfFishMode = cbname; 
            canvases.repaint(); 
        } 
        return true; 
    } 
}