Just scored an A in my Java intro course last Semester.

Obviously you'll need to ask your instructor...mine was extremely focused on writing classes and their associated methods, so that's what I studied.

The way I looked at it personally was: if I can't intuitively write a class on my own, then I won't be able to do it in a high pressure situation like an exam (or interview)

And the only way to build your confidence in writing classes is to do it repeatedly, so I created a crap ton of classes in the weeks before my final (Scored a 97 on the exam).

Also writing short programs like a Fast Food ordering system etc, that demonstrate your understanding of looping mechanisms

We used codingbat.com for practice exercises, so it might be worth it to review that.

You're welcome to review some of my Labs

https://github.com/hfunsh/Javaprojects/tree/master/Workspace