Java tutorial
import java.awt.Frame; import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.geom.Ellipse2D; public class MainClass extends Frame { public static void main(String[] args) { (new MainClass()).setVisible(true); } public MainClass() { setSize(250, 250); } public void paint(Graphics g) { Graphics2D g2d = (Graphics2D) g; Ellipse2D e = new Ellipse2D.Float(10, 10, 200, 200); g2d.clip(e); g2d.fillRect(40, 60, 500, 500); } }