Filling shape with texture

[kyojin]

I'm trying to improve one of my project by adding texture to a shape. The shape is oval, it basically the moon. I want it to have a realistic feel rather than gradient fill. So I look up some tutorial and this is what i got from http://java.sun.com/products/java-media/jai/forDevelopers/jai1_0_1guide-unc/Graphics.doc.html

// Create a buffered image texture patch of size 5 X 5.
     BufferedImage bi = new BufferedImage(5, 5,
                            BufferedImage.TYPE_INT_RGB);
     Graphics2D big bi.createGraphics();

     // Render into the BufferedImage graphics to create the texture.
     big.setColor(Color.green);
     big.fillRect(0, 0, 5, 5);
     big.setColor(Color.lightGray);
     big.fillOval(0, 0, 5, 5);

     // Create a texture paint from the buffered image.
     Rectangle r = new Rectangle(0, 0, 5, 5);
     TexturePaint tp = new
         TexturePaint(bi, r, TexturePaint.NEAREST_NEIGHBOR);

     // Add the texture paint to the graphics context.
     g2.setPaint(tp);

     // Create and render a rectangle filled with the texture.
     g2.fillRect(0, 0, 200, 200);

I try to run it and it show an error. Can someone explain to me what part of that program can I change to choose my own texture and fillOval? or give a nice tutorial for beginner?