public void insert(E value) {
   LinkedListElement<E> element = new LinkedListElement<E>(value);
   LinkedListElement<E> keep = null;
   keep = current.next;
   current.next = element;
   element.next = keep;
   current = element;
 }
 public void append(E value) {
   LinkedListElement<E> element = new LinkedListElement<E>(value);
   tail.next = element;
   tail = element;
 }