How good is the world of java advanced for a career these days? I learned java basics (collections,OOP, syntaxes, threads, a little bit of spring,etc) aka core java in college and then went straight to Android dev.

I am thinking of learning about the contents of java ee and me or whatever "advanced" java is. How tough is it? What is the career in it? How good is the possibility of getting a fresher job in it?