java iterator with index parameter

hi a normal iterator for a LinkedList would be the following, however, how do we build an iterator that returns an iterator starting at a specified index? How do we build:

public Iterator<E>iterator(int index)???  

thanks! normal Iterator:

    public Iterator<E> iterator( )
    {
        return new ListIterator();
    }

private class ListIterator implements Iterator<E>
    {
        private Node current;

        public ListIterator()
        {
            current = head; // head in the enclosing list
        }
        public boolean hasNext()
        {
            return current != null;
        }
        public E next()
        {
            E ret = current.item;
            current = current.next;
            return ret;
        }
        public void remove() { /* omitted because optional */ }
    }