Java News from Sunday, September 4, 2005

David Hovemeyer and Bill Pugh have posted FindBugs 0.9.3, an automated open source tool for finding potential bugs in Java code. New detectors in this version include:

• abstract methods that implement an interface
• stores of literal booleans inside if or while expressions
• final classes that declare protected fields
• subclass methods that simply forward, verbatim to the superclass
• instances where code is attempting to write an object out via an implemention of DataOutput, but the object is not guaranteed to be Serializable

I tested this out on XOM where it "found" over 3000 bugs. Almost all of them were false positives. In particular, it objected to the numerous times XOM uses the same code in different branches of a switch statement. (Sometimes it's important to do this to optimize by using table switches.) However, it did find one minor but real problem that is now fixed. If I hadn't used this tool frequently in the past, it would have found more.