I know that LinkedLists are implemented in a doubly-linked way, so each node has a next and a previous pointer. However, I couldn't find what syntax to use to access the previous nodes. I looked in the Java API, and there is a method to iterate through a linkedlist backwards. That to me, implies that there is an easy way to access previous nodes.
I am trying to design an experiment to prove that LinkedLists isn't just a singly-linked list, but I can't think of how to do so without moving backwards in linkedlists.
How do I move backwards in a LinkedList?
LinkedList has a listIterator(int) method. So you can use:
// Start at the end...
ListIterator<Foo> iterator = list.listIterator(list.size());
while (iterator.hasPrevious()) {
Foo foo = iterator.previous();
}
That doesn't prove that it's a doubly-linked list - that could be implemented very inefficiently in a single-linked list, for example - but that's how I'd go about iterating over a linked list backwards.