In a major refactoring exercise I have split the SimpleDBM modules into two higher level packages. The Latch Manager, the Object Registry and the Util packages all go under the package org.simpledbm.common. The rest of the packages go under org.simpledbm.rss. I decided to use the acronym RSS for the low level data management API in honour of System R. System R called its low level API Research Storage System or RSS in short. See the paper Morton M. Astrahan, Mike W. Blasgen, Donald D. Chamberlin, Kapali P. Eswaran, Jim Gray, Patricia P. Griffiths, W. Frank King III, Raymond A. Lorie, Paul R. McJones, James W. Mehl, Gianfranco R. Putzolu, Irving L. Traiger, Bradford W. Wade, Vera Watson: System R: Relational Approach to Database Management. ACM Trans. Database Syst. 1(2): 97-137(1976).
Of course, all this refactoring has left CVS in a mess, as now there are many empty subdirectories under src/org/simpledbm.
I have also been working on a Developer's Reference Manual. This will hopefully contain sufficient information for interested hackers and database technology enthusiasts to play around with various modules. You can access the document here. I would welcome any feedback.
Finally, the SimpleDBM project has now graduated out of the incubator at www.java.net. This should lead to greater exposure and interest in the project.