Do we ever need to use Iterators on ArrayList?

Question

Yesterday, when I was answering to question getting ConcurrentModificationException error while using iterator and remove I added a notice that

It\'s

Answer 1

You are probably talking about explicitly using an iterator (since the : operator is also using the iterator behind the scenes).

Say you want to have two "pointers" going over the array but the speed depends on the actual element values. How would you do this without explicitly using iterators (and without elementAt of course).

For example (pseudo code):

element1 = first element;
element2 = first element;
while(element1.hasNext && element2.hasNext)
{
    if(element1 * 2 < element)
    {
        element2 = element2.next;
    }
    else
    {
        element1 = element1.next;
    }

    //do something with the pair of elements
}