Welcome to the forums!
Syntactically, preliminary tests show everything is ok.
Logically, I didn't read your code because frankly I don't have the time, this will be left to you. Also, you need to be specific about issues here... what are you looking to test? What are you looking to list, how are you planning to add to the list, what objects are you listing, what are your bounds... etc. I can't think this stuff up for you because it's your project.
Create test classes or main() to run tests on your code. If things do not
come back the way you initially intended- then come back here and post the specifics of it and we can then take a look at it. I'd be happy to.
See you around!
