I think you need to memorize the common functions for the Wrapper classes and the Math functions. Questions might be asked on the commonaly used methods like Math.floor() etc. Go through some of the
SCJP mock exams and see the type of questions asked on the Wrapper class methods. That would give you a general idea.
It should be pretty easy memorizing, as most of the methods speak for themselves. But you still have to know to which Wrapper class they belong to.
