I just read that a company called Enerjy  did a “fault proneness”
analysis of many Java open-source projects, and DrJava was among them . We rank in the lower half, but just above Eclipse.
I don’t exactly know how the rules are weighted, but they are pretty
arbitrary. One thing I noticed, for example, is this rule: “You can
configure JAVA0020 for allowable names. The default is for the name to
begin with a letter followed by letters, digits or underscores.”
We consistently prefix fields with an underscore, so we consistently
violate their convention. I don’t put a lot of trust into metrics like
these, particularly when they are ill-configured.
I still thought this was interesting.