How to have List Iterator start at a given index?

Question

I have a linked list and I need to make method that returns an iterator at a given point in the list. I currently have an iterator that starts at the head:

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Answer 1

Simply use the listIterator(index); method from List, in which index is an int resembling the starting index. Edit: in your case it would be

List<...> list = ...;
return list.listIterator(x);

Answer 2

So I ended up going with this.

public Iterator<E> iterator(int x){

    Iterator<E> it = new ListIterator();

    for (; x > 0; --x){
        it.next(); 
    }
    return it;
}

Given more range I might have added a constructor but without being able to change much this worked the best.

Answer 3

Without seeing your implementation, the trivial way to do this is:

public Iterator<E> iterator(int x) {
    if (x < 0 || this.size() < x) {
        throw new IndexOutOfBoundsException();
    }

    Iterator<E> it = new ListIterator();

    for (; x > 0; --x) {
        it.next(); // ignore the first x values
    }
    return it;
}

Otherwise, you could traverse the list to the xth node, but there's no reason you can't do it this way.