This comment doesn't seem to describe this well. It's really making the underlying list equivalent to the list it was given. This seems a little strange because it's not going to reference the given list, and is actually modifying whatever it's currently pointing to. This doesn't seem to match the naming either - updateList sounds like something that checks the current state of the list versus the one it was given.

This logic seems to correspond to something like ```loadFromList(List<T> list)```. And I would comment something like "sets the underlying lists contents to match the items currently in the given list".