�� I have a java applet program (yanhua.java) need help!!!

Question

�� I have a java applet program (yanhua.java) that use mouse click a area show a fireworks, the applet program that a java fan mail me. Now i find some bug in the program, can you help me? thank in advance!
The backdrop of the question: The yanhua.java applet program works well. But one day, i install j2re 1.4.1 plugin for my microsfot Internet Explorer, i run the yanhua.java applet program again, it show difficult(i move my mouse in the area, slowness), the fireworks is not fluent. Then i try my best to find the cause , i get some information, the following: yanhua.java run in j2re 1.4.1 plugin,it will deplete 100% cpu; else yanhua.java does not run in j2re 1.4.1 plugin, it will deplete 90%--95% cpu too; but my computer c3 1G cpu and 256MB memory, without running other program at that time. So i can have the assurance to say that the yanhua.java have some bug or error. can you help me to find all bug in yanhua.java? thank you very much!!!
i want to solve the question: finding all bug in yanhua.java
NOTE:
1��fireworks show specially good effect(a yanhua.java applet) you can look at:
http://www.3ren.net/down/java/yanhua.html
2��all program you can get from http://www.3ren.net/down/java/yanhua.rar
/*************************yanhua.java******************************
import java.applet.Applet;
import java.applet.AudioClip;
import java.awt.*;
import java.awt.image.MemoryImageSource;
import java.util.Random;
public class yanhua extends Applet
implements Runnable
private int m_nAppX;
private int m_nAppY;
private int m_centerX;
private int m_centerY;
private int m_mouseX;
private int m_mouseY;
private int m_sleepTime;
private boolean isError;
private boolean m_isPaintFinished;
boolean isRunning;
boolean isInitialized;
Thread runner;
int pix0[];
MemoryImageSource offImage;
Image dbImg;
int pixls;
int pixls2;
Random rand;
int bits;
double bit_px[];
double bit_py[];
double bit_vx[];
double bit_vy[];
int bit_sx[];
int bit_sy[];
int bit_l[];
int bit_f[];
int bit_p[];
int bit_c[];
int bit_max;
int bit_sound;
int ru;
int rv;
AudioClip sound1;
AudioClip sound2;
public yanhua()
m_mouseX = 0;
m_mouseY = 0;
m_sleepTime = 5;
isError = false;
isInitialized = false;
rand = new Random();
bits = 10000;
bit_px = new double[bits];
bit_py = new double[bits];
bit_vx = new double[bits];
bit_vy = new double[bits];
bit_sx = new int[bits];
bit_sy = new int[bits];
bit_l = new int[bits];
bit_f = new int[bits];
bit_p = new int[bits];
bit_c = new int[bits];
ru = 50;
rv = 50;
public void init()
String s = getParameter("para_bits");
if(s != null)
bits = Integer.parseInt(s);
s = getParameter("para_max");
if(s != null)
bit_max = Integer.parseInt(s);
s = getParameter("para_blendx");
if(s != null)
ru = Integer.parseInt(s);
s = getParameter("para_blendy");
if(s != null)
rv = Integer.parseInt(s);
s = getParameter("para_sound");
if(s != null)
bit_sound = Integer.parseInt(s);
m_nAppX = this.getSize().width;
m_nAppY = this.getSize().height;
m_centerX = m_nAppX / 2;
m_centerY = m_nAppY / 2;
m_mouseX = m_centerX;
m_mouseY = m_centerY;
resize(m_nAppX, m_nAppY);
pixls = m_nAppX * m_nAppY;
pixls2 = pixls - m_nAppX * 2;
pix0 = new int[pixls];
offImage = new MemoryImageSource(m_nAppX, m_nAppY, pix0, 0, m_nAppX);
offImage.setAnimated(true);
dbImg = createImage(offImage);
for(int i = 0; i < pixls; i++)
pix0[i] = 0xff000000;
sound1 = getAudioClip(getDocumentBase(), "firework.au");
sound2 = getAudioClip(getDocumentBase(), "syu.au");
for(int j = 0; j < bits; j++)
bit_f[j] = 0;
isInitialized = true;
start();
public void run()
while(!isInitialized)
try
Thread.sleep(200L);
catch(InterruptedException interruptedexception) { }
do
for(int j = 0; j < pixls2; j++)
int k = pix0[j];
int l = pix0[j + 1];
int i1 = pix0[j + m_nAppX];
int j1 = pix0[j + m_nAppX + 1];
int i = (k & 0xff0000) >> 16;
int k1 = ((((l & 0xff0000) >> 16) - i) * ru >> 8) + i;
i = (k & 0xff00) >> 8;
int l1 = ((((l & 0xff00) >> 8) - i) * ru >> 8) + i;
i = k & 0xff;
int i2 = (((l & 0xff) - i) * ru >> 8) + i;
i = (i1 & 0xff0000) >> 16;
int j2 = ((((j1 & 0xff0000) >> 16) - i) * ru >> 8) + i;
i = (i1 & 0xff00) >> 8;
int k2 = ((((j1 & 0xff00) >> 8) - i) * ru >> 8) + i;
i = i1 & 0xff;
int l2 = (((j1 & 0xff) - i) * ru >> 8) + i;
int i3 = ((j2 - k1) * rv >> 8) + k1;
int j3 = ((k2 - l1) * rv >> 8) + l1;
int k3 = ((l2 - i2) * rv >> 8) + i2;
pix0[j] = i3 << 16 | j3 << 8 | k3 | 0xff000000;
rend();
offImage.newPixels(0, 0, m_nAppX, m_nAppY);
try
Thread.sleep(m_sleepTime);
catch(InterruptedException interruptedexception1) { }
} while(true);
public void update(Graphics g)
paint(g);
public void paint(Graphics g)
g.drawImage(dbImg, 0, 0, this);
public void start()
if(isError)
return;
isRunning = true;
if(runner == null)
runner = new Thread(this);
runner.start();
public void stop()
if(runner != null)
runner.stop();
runner = null;
public boolean mouseMove(Event event, int i, int j)
m_mouseX = i;
m_mouseY = j;
return true;
public boolean mouseDown(Event event, int i, int j)
m_mouseX = i;
m_mouseY = j;
int k = (int)(rand.nextDouble() * 256D);
int l = (int)(rand.nextDouble() * 256D);
int i1 = (int)(rand.nextDouble() * 256D);
int j1 = k << 16 | l << 8 | i1 | 0xff000000;
int k1 = 0;
for(int l1 = 0; l1 < bits; l1++)
if(bit_f[l1] != 0)
continue;
bit_px[l1] = m_mouseX;
bit_py[l1] = m_mouseY;
double d = rand.nextDouble() * 6.2800000000000002D;
double d1 = rand.nextDouble();
bit_vx[l1] = Math.sin(d) * d1;
bit_vy[l1] = Math.cos(d) * d1;
bit_l[l1] = (int)(rand.nextDouble() * 100D) + 100;
bit_p[l1] = (int)(rand.nextDouble() * 3D);
bit_c[l1] = j1;
bit_sx[l1] = m_mouseX;
bit_sy[l1] = m_nAppY - 5;
bit_f[l1] = 2;
if(++k1 == bit_max)
break;
if(bit_sound > 1)
sound2.play();
return true;
public boolean mouseExit(Event event, int i, int j)
m_mouseX = i;
m_mouseY = j;
return true;
void rend()
boolean flag = false;
boolean flag1 = false;
boolean flag2 = false;
for(int k = 0; k < bits; k++)
switch(bit_f[k])
default:
break;
case 1: // '\001'
bit_vy[k] += rand.nextDouble() / 50D;
bit_px[k] += bit_vx[k];
bit_py[k] += bit_vy[k];
bit_l[k]--;
if(bit_l[k] == 0 || bit_px[k] < 0.0D || bit_py[k] < 0.0D || bit_px[k] > (double)m_nAppX || bit_py[k] > (double)(m_nAppY - 3))
bit_c[k] = 0xff000000;
bit_f[k] = 0;
} else
if(bit_p[k] == 0)
if((int)(rand.nextDouble() * 2D) == 0)
bit_set((int)bit_px[k], (int)bit_py[k], -1);
} else
bit_set((int)bit_px[k], (int)bit_py[k], bit_c[k]);
break;
case 2: // '\002'
bit_sy[k] -= 5;
if((double)bit_sy[k] <= bit_py[k])
bit_f[k] = 1;
flag2 = true;
if((int)(rand.nextDouble() * 20D) == 0)
int i = (int)(rand.nextDouble() * 2D);
int j = (int)(rand.nextDouble() * 5D);
bit_set(bit_sx[k] + i, bit_sy[k] + j, -1);
break;
if(flag2 && bit_sound > 0)
sound1.play();
void bit_set(int i, int j, int k)
int l = i + j * m_nAppX;
pix0[l] = k;
/*********************************end*******************************

Answer 1

no one help me???????????