No problem... I've never actually run in to a case where I've had to think about this (other than academically)--what's your usecase?
And welcome to JavaRanch!
posted 8 years ago
what's your usecase?
You got it in one: academics. I make some interface source files and a jar file full of classes available in a read-only public directory. I try to discourage copying files to avoid obsolete-file problems, but compilations were failing because javac was trying to write the class files into the public directory. I resisted describing -d, but I may have to give in.