This applet lets you use your computer keyboard like a music keyboard.
Source is included.
Available in download. See the configuration file. In this tutorial Johannes Wallroth gives a series of fairly simple examples in order to enable you to get a grasp of the possibilities and the syntax of the Java language. Take a step by step walk through the process of building a Java applet with programmer Bavo Bruylandt. Throughout the Java tutorial all new lines of code are explained.