btpanel.java

The applet illustrates the behaviour of binary search trees, Searching and Sorting Algorithms, Self-

        case 1: // '\001'
        {
            int state = setSpeed(cmd) ? 0 : 1;
            tool.setState(command, state);
            break;
        }

        case 2: // '\002'
        {
            thoughtful = !thoughtful;
            int state = thoughtful ? 0 : 1;
            tool.setState(command, state);
            displayMessage("", MSG.THINKING[state], 1);
            break;
        }

        case 3: // '\003'
        {
            direction = -direction;
            int state = direction != 1 ? 1 : 0;
            tool.setState(command, state);
            displayMessage("", MSG.ASCEND[state], 1);
            break;
        }

        case 4: // '\004'
        {
            classic = !classic;
            int state = classic ? 0 : 1;
            tool.setState(command, state);
            displayMessage("", MSG.SHAPE[state], 1);
            break;
        }

        case 5: // '\005'
        {
            mute = !mute;
            int state = mute ? 0 : 1;
            tool.setState(command, state);
            displayMessage("", MSG.SOUND[state], 1);
            break;
        }

        case 9: // '\t'
        {
            if(tree.isAVL())
            {
                factors = !factors;
                int state = factors ? 0 : 1;
                tool.setState(command, state);
                displayMessage("", MSG.FACTORS[state], 1);
            } else
            {
                displayMessage("", MSG.FACTORS[2], 3);
            }
            break;
        }

        case 6: // '\006'
        {
            setTreeMode(2, !tree.isSPL());
            int state = tree.isSPL() ? 0 : 1;
            tool.setTreeMode(command, state);
            displayMessage("", MSG.SPL[state], 0);
            break;
        }

        case 7: // '\007'
        {
            setTreeMode(3, !tree.isRBL());
            int state = tree.isRBL() ? 0 : 1;
            tool.setTreeMode(command, state);
            displayMessage("", MSG.RBL[state], 0);
            break;
        }

        case 8: // '\b'
        {
            setTreeMode(1, !tree.isAVL());
            int state = tree.isAVL() ? 0 : 1;
            tool.setTreeMode(command, state);
            displayMessage("", MSG.AVL[state], 0);
            break;
        }

        case 10: // '\n'
        {
            if(!rotate(direction * cmd))
                break;
            int state;
            if(tree.isAVL())
            {
                state = tree.isAVLcompliant(tree.getRoot()) ? 0 : 1;
                addMessage("", MSG.AVLCMPL[state], 0);
                if(state == 1)
                {
                    setTreeMode(1, false);
                    tool.setTreeMode(8, 1);
                }
                break;
            }
            if(!tree.isRBL())
                break;
            state = tree.isRBLcompliant(tree.getRoot()) ? 0 : 1;
            addMessage("", MSG.RBLCMPL[state], 0);
            if(state == 1)
            {
                setTreeMode(3, false);
                tool.setTreeMode(7, 1);
            }
            break;
        }

        case 11: // '\013'
        {
            if(!splay())
                break;
            if(tree.isAVL())
            {
                setTreeMode(1, false);
                tool.setTreeMode(8, 1);
                break;
            }
            if(tree.isRBL())
            {
                setTreeMode(3, false);
                tool.setTreeMode(7, 1);
            }
            break;
        }
        }
    }

    public void setTreeMode(int mode, boolean state)
    {
        tree.setMode(mode, state);
        if(tree.isAVL())
        {
            if(!tree.isAVLcompliant(tree.getRoot()))
                reinsertTree(1);
            else
                resetNodes();
        } else
        {
            factors = false;
        }
        if(tree.isSPL())
            resetNodes();
        if(tree.isRBL())
            reinsertTree(3);
        else
            resetColors();
    }

    public void reinsertTree(int mode)
    {
        stopFID();
        BSTree temp = new BSTree(mode);
        for(BTNode node = tree.getRoot(); node != null; node = node.nextPrO())
            temp.insert(node.getData());

        tree = temp;
        temp = null;
        resetNodes();
    }

    public void setTreeSize(int cmd)
    {
        if(cmd == 4)
        {
            if(xstep > 8)
                xstep--;
            else
                displayMessage("", "Minimum size. ", 3);
        } else
        if(cmd == 6)
        {
            if(xstep < 48)
                xstep++;
            else
                displayMessage("", "Maximum size. ", 3);
        } else
        if(cmd == 8)
        {
            if(ystep < 96)
                ystep++;
            else
                displayMessage("", "Maximum size. ", 3);
        } else
        if(cmd == 2)
        {
            if(ystep > 16)
                ystep--;
            else
                displayMessage("", "Minimum size. ", 3);
        } else
        if(cmd == 5)
        {
            xstep = 16;
            ystep = 32;
            treetop.setLocation(400, 56);
            shakeNodes();
            displayMessage("", "Default tree size. ", 0);
        } else
        if(cmd == 1)
            treetop.move(0, -2);
        else
        if(cmd == 3)
            treetop.move(0, 2);
        else
        if(cmd == 7)
            treetop.move(-2, 0);
        else
        if(cmd == 9)
            treetop.move(2, 0);
    }

    public boolean setSpeed(int cmd)
    {
        if(cmd == 4)
        {
            if(SPEED > 1)
            {
                SPEED--;
                displayMessage(String.valueOf(SPEED), "Animation speed: {0}. ", 0);
            } else
            {
                displayMessage(String.valueOf(1), "Minimum speed: {0}. ", 3);
            }
            speed = SPEED;
        } else
        if(cmd == 6)
        {
            if(SPEED < 10)
            {
                SPEED++;
                displayMessage(String.valueOf(SPEED), "Animation speed: {0}. ", 0);
            } else
            {
                displayMessage(String.valueOf(10), "Maximum speed: {0}. ", 3);
            }
            speed = SPEED;
        } else
        if(cmd == 5)
        {
            if(speed == 0)
                speed = SPEED;
            else
                speed = 0;
            int state = speed <= 0 ? 1 : 0;
            displayMessage("", MSG.PAUSED[state], 1);
        } else
        if(cmd == 2)
        {
            speed = SPEED = 10;
            tool.setState(1, 0);
            displayMessage(String.valueOf(10), "Maximum speed: {0}. ", 0);
        } else
        if(cmd == 8)
        {
            speed = SPEED = 1;
            tool.setState(1, 0);
            displayMessage(String.valueOf(1), "Minimum speed: {0}. ", 0);
        }
        thinkcount = 48 + 160 / SPEED;
        return speed > 0;
    }

    public boolean rotate(int side)
    {
        if(!getPermission(4))
            return false;
        if(lastpick == null)
        {
            displayMessage("", "Pick a node first. ", 3);
            return false;
        }
        String key = lastpick.getKey();
        if(lastpick.getChild(-side) == null)
        {
            displayMessage(key, "Cannot rotate {0} " + getSideName(side), 3);
            return false;
        } else
        {
            lastpick = rotate(lastpick, side);
            displayMessage(key, "{0} rotated " + getSideName(side), 1);
            applet.setText(lastpick.getKey());
            return true;
        }
    }

    public boolean splay()
    {
        int i = 0;
        if(!getPermission(10))
            return false;
        target = lastpick;
        if(target == null)
        {
            displayMessage("", "Pick a node first. ", 3);
            return false;
        } else
        {
            pinball.setLocation(target);
            pinball.setData(target.getData());
            startSPL();
            return true;
        }
    }

    public boolean getPermission(int mode)
    {
        if(speed == 0)
        {
            displayMessage("", "Animation paused.  Resume? ", 3);
            return false;
        }
        if(pinball.getMode() != 0 && pinball.getMode() != mode || pinball.getEvent() != 0)
        {
            displayMessage("", "Another operation is in progress. ", 3);
            return false;
        }
        if(tree.isEmpty() && mode != 5)
        {
            displayMessage("", "The tree is empty. Operation not permitted. ", 3);
            return false;
        } else
        {
            return true;
        }
    }

    public void start()
    {
        if(engine == null)
        {
            engine = new Thread(this);
            engine.start();
        }
        createBackImage();
        createMainImage();
        populate();
    }

    public void run()
    {
        for(Thread thread = Thread.currentThread(); engine == thread;)
        {
            try
            {
                Thread.sleep(80L);
            }
            catch(InterruptedException _ex) { }
            animateTree();
            repaint();
        }

    }

    public void stop()
    {
        if(engine != null && engine.isAlive())
            engine.stop();
        engine = null;
    }

    public synchronized void update(Graphics g)
    {
        paint(g);
    }

    public boolean cycle(int count, int n)
    {
        return (float)(count / n) == (float)count / (float)n;
    }

    public String getSideName(int side)
    {
        int i = direction * side + 1;
        return MSG.SIDENAME[i];
    }

    public void createBackImage()
    {
        backImage = createImage(800, 340);
        Graphics g = backImage.getGraphics();
        for(int i = 0; i < MODE.BALL.length; i++)
            g.drawImage(applet.getBall(i), 0, 0, null);

        applet.playSound(2);
        g.setColor(Color.white);
        g.fill3DRect(0, 0, 800, 340, true);
        g.setColor(Color.black);
        g.drawRect(0, 0, 799, 339);
    }

    public void createMainImage()
    {
        mainImage = createImage(800, 340);
        bg = mainImage.getGraphics();
        fm = bg.getFontMetrics();
        tool.setFontMetrics(fm);
    }

    public void populate()
    {
        new Random();
        for(int i = 0; i < 12; i++)
        {
            BTData data = new BTData(applet.getTextRandom());
            tree.insert(data);
        }

        resetNodes();
    }

    public void setToolState()
    {
        tool.setState(0, 0);
        tool.setState(1, speed <= 0 ? 1 : 0);
        tool.setState(2, thoughtful ? 0 : 1);
        tool.setState(3, direction != 1 ? 1 : 0);
        tool.setState(4, classic ? 0 : 1);
        tool.setState(5, mute ? 0 : 1);
        tool.setState(6, tree.isSPL() ? 0 : 1);
        tool.setState(7, tree.isRBL() ? 0 : 1);
        tool.setState(8, tree.isAVL() ? 0 : 1);
        tool.setState(9, factors ? 0 : 1);
        tool.setState(10, 0);
        tool.setState(11, 0);
    }

    static final int XSIZE = 800;
    static final int YSIZE = 340;
    static final int XOFF = 2;
    static final int YOFF = 6;
    static final int ON = 0;
    static final int OFF = 1;
    static final int NA = 2;
    static final int YSTEP = 32;
    static final int XSTEP = 16;
    static final int BALLSIZE = 13;
    static final int CIRCLESIZE = 18;
    static final int BOUNCESIZE = 6;
    static final int NODECOUNT = 12;
    static final int BOUNCECOUNT = 1;
    static final int THINKCOUNT = 48;
    static final int SLEEPTIME = 80;
    static final Color GRAYCOLOR = new Color(224, 224, 224);
    public int xstep;
    public int ystep;
    public int speed;
    public int SPEED;
    public boolean thoughtful;
    public int thinkcount;
    public boolean classic;
    public boolean mute;
    public boolean factors;
    public int direction;
    public int minmax;
    BSTree tree;
    BTNode treetop;
    BTNode pinball;
    BTNode pinfall;
    BTNode target;
    BTNode picknode;
    BTNode lastpick;
    BTNode lastnode;
    BTNode swapnode;
    BTNode rootnode;
    BTNode fallnode;
    int order;
    int count;
    boolean rotatequeued;
    boolean rotating;
    String message;
    Thread engine;
    BTApplet applet;
    BTTool tool;
    Image backImage;
    Image mainImage;
    Graphics bg;
    FontMetrics fm;
    int animation;

}