The above is a demonstration of a very simple applet that uses double-buffered animation. Click and drag to see what it does.
Honestly, the RippleApplet's a little more complicated than it really needs to be. I hope it's not too confusing.
To see how I included the applet in this web page, use your browser menu to "View Source". You might want to see a demo of how the java and class files are laid out in the directory; click here to see a directory listing.