RTF: How can I implement conditional compilation in Java?

In terms of your underlying design question, I suggest using the Abstract Factory or the Factory Method design patterns (see the Patterns FAQ for more information).

Mark,

I had a similar problem in the past. In my case I was using a specific implementation of an interface, based on a series of factor. The simplest solution (I had no time to think of something better) was to insert the right class and have my code trying to create a new instance of the class using Class.forName().newINstance(). If that was giving me a ClassNotFoundException, then I was initializing the other.

I know, this is not the best solution but I hope it could give you some hints.