One tool, which gathers quite niche statistics is Testability Explorer. It operates on Java byte code, providing stats for cyclomatic complexity, mutable global state and some other things. It s free and open-source under the Apache 2.0 license.
As I said it is very niche, and probably won t give metrics which are as easy to relate to as LOC. However, what s interesting is that you would be able to compare the projects you run it on against several well known open-source projects. This would perhaps make the results more useful.
Another tool which I recently used is SLOCCount. It s a command line tool designed to give statistics for many different languages, including Java. After failing to run JavaNCSS on a large codebase (it complained of too many files) I got this tool running no problem, for a very large codebase (IntelliJ IDEA). A nice feature is that it takes very little configurability, I didn t even have to tell it to look for *.java
files, it recognised different languages automatically and reported on them.
The downside to SLOCCount is if you re running Windows - you ll have to use Cygwin to run it.