Onjava

<p><a href="http://www.onjava.com/pub/a/onjava/2005/06/08/prevayler.html">Prevalence: Transparent, Fault-Tolerant Object Persistence</a> by Jim Paterson -- Want to persist your objects, with transactional integrity? You probably assume you're going to be using a database, but not so fast--for lighter uses, particularly for prototyping and testing, the idea of "prevalence" may make more sense. Jim Paterson introduces it by way of Prevayler, a popular prevalence framework.</p>