Well, even just that is already twice again as much space per item, right? Then you have to add to that whatever the expense of a
Java object is in general, because each link is an Object with three members (the item and those two pointers.) The exact size isn't specified (it's VM dependent,) but it's at
least another 8 bytes in any VM I've seem, and 16 bytes is more typical. That means (assuming 4-byte pointers) that LinkedList uses 24 bytes per item, as opposed to 4 for ArrayList -- 600% more storage per item.