Well, I suppose it was a bit of hyperbole on my part, but the thought of someone saying "I know Java" made me think of something like that "I know Kung Fu" mome

Well, I suppose it was a bit of hyperbole on my part, but the thought of someone saying "I know Java" made me think of something like that "I know Kung Fu" moment from The Matrix, as if there's some amount of knowledge after which you just have the skill. I consider Java to be one of these things like Kung Fu, or Chess, or photography, where thinking that you now know it just means that you're so early in your learning process that you can't see the full lay of the land yet.