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Yasir Khan
3,937 PointsHow do i compare the last item of a HashSet with something else?
basically I need my animation to stop as soon as the last ball in my HashSet goes past the Xposition, which is 550.
so far this is what I have but it is wrong
if(ball[ballSet.size()].getXPosition() >= 550) { finished = true;
2 Answers
Seth Kroger
56,416 PointsIt looks like you're confusing array, Set, and List. The first problem is you're using an array lookup on an object that isn't an array.
Second, the concept of "last item" isn't compatible with the concept of Set. Think of a Set more like a bag or sack of unique items. An item can be in the bag or not but it doesn't matter how the items get jumbled together. The different implementations like HashSet and TreeSet are just different ways to fit the items into the bag.
It looks like you should be using an array (the number of balls you need is fixed throughout the program), a List (the number of balls you need changes dynamically), or reconsider what "last ball" means in your program.
Yasir Khan
3,937 PointsThank you very much Seth Kroger your explanation helped a lot.