Find all unused variable

Question

Normally it's easy to see unused variables in Netbeans, just a grey squiggly line.

But how would I find all of these unused variables in my project or of a single class?

Reason: I'm debugging a code base which had lots of copy and paste, but it wasn't done carefully. There's many bug of not replacing with the right variable after copy and paste.

Answer 1

You could run something like FindBugs on it.

FindBugs

Looking at the bug list it has

UuF: Unused field (UUF_UNUSED_FIELD) This field is never used. Consider removing it from the class.

You could filter on just this, but it is a good idea to run this on all code all the time, it is amazing what it finds.