* {@code ForwardingIterator}.
 *
 * @author Kevin Bourrillion
 * @since 2.0
 */
@GwtCompatible
public abstract class ForwardingIterator<T extends @Nullable Object> extends ForwardingObject
    implements Iterator<T> {

  /** Constructor for use by subclasses. */
  protected ForwardingIterator() {}

  @Override
  protected abstract Iterator<T> delegate();

 * methods on the {@code ForwardingListIterator}.
 *
 * @author Mike Bostock
 * @since 2.0
 */
@GwtCompatible
public abstract class ForwardingListIterator<E extends @Nullable Object>
    extends ForwardingIterator<E> implements ListIterator<E> {

  /** Constructor for use by subclasses. */
  protected ForwardingListIterator() {}

  @Override
  protected abstract ListIterator<E> delegate();

  @Override