There's knowing Java as in having a grasp on the language syntax itself and some parts of it's standard libraries (and of course OOP, as I think most would agre

There's knowing Java as in having a grasp on the language syntax itself and some parts of it's standard libraries (and of course OOP, as I think most would agree it's a sine qua non for a programmer nowadays), and then there's knowing Java as in JEE and the miriad of associated apis, frameworks and tools. While I (as an employer) am not interested in the later, I would pretty much expect any decent programmer to be familiar with Java at least on some basic level.