bouncing ball using JApplet

[src]
import java.awt.*;
import javax.swing.*;
import java.util.*;

public class test extends JApplet implements Runnable
{
public void init(){}
public void paint(Graphics g)
{
int dx= -1,dy= -1;
int x=0,y=0,o=0;
Color c[]={Color.red,Color.green,Color.blue};
Color l=Color.red;
Random r=new Random();
for (int i=0;;i++)
{
try{
if (dx<0||dy<0)
{
if (x<0||y<0)
{
dx=2;
dy=1;
l=c[o%3];
o++;
}
}
else if (dx>0||dy>0)
{
if (x>490||y>290)
{
dx= -2;
dy= -1;
l=c[o%3];
o++;
}
}
x+=dx;
y+=dy;
g.setColor(l);
g.fillOval(x,y,10,10);
Thread.sleep(10);}
catch(Exception e){}
g.setColor(Color.white);
g.fillRect(0,0,500,300);
}
}
public void run()
{
try{Thread.sleep(10);}
catch(Exception e){}
repaint();
}
}[/src]