请教：Applet小球放大的例子？

Question

帮你改了一下（已测试）
import java.awt.*;
import java.applet.*;public class Applet1 extends Applet implements Runnable 
{
int currentX=0,currentY =0;
Thread m_Draw=null;
public void init()
{
m_Draw=new Thread(this);
}
public void paint(Graphics g)
{
g.setColor(Color.green);
mycircle(g,getSize().width/2,getSize().height/2,currentX,currentY);
}
public void start()
{
m_Draw.start();
try
{
Thread.sleep(50);
}catch(InterruptedException e){}
}
public void stop()
{
if(m_Draw.isAlive())
m_Draw.stop();
}
public void run()
{
try
{
int i=1;
while(true)
{
currentX=currentX+i;
currentY=currentY+i;
if(currentX>100||(currentY>100))
{
i=-1;
}
else if(currentX<=0||currentY<=0){
currentX=0;
currentY=0;
i=1;
} repaint();
Thread.sleep(100);
}
}
catch(InterruptedException e){}
}
public void mycircle(Graphics g,int x,int y,int rx,int ry)
{
g.fillOval(x-rx,y-ry,2*rx,2*ry);
}
}
记得给分，老兄