I wanted to put in an add method but we are supposed to use what is in our outline.
Basically, you are writing test code. If you modify your class with special methods just for your test code, aren't you just wasting a testing opportunity?
Your class seems to have two add methods that add individual elements -- addBefore and addAfter. Do they work correctly? Have you tested them? If you have tested them, I am assuming that you wrote a loop that load them up? And if you did, can you reuse that testing code here?
Henry