Use of Control Loops in Applets

import java.awt.*;
import java.applet.*;
public class Loop extends Applet
{
public void paint(Graphics g)
{
for(int i=0; i<=4; i++)
{
if(i%2)==0)
g.drawOval(120, i*60+10, 50, 50);
else
g.fillOval(120, 1*60+10, 50, 50);
}
}
}