* MinMaxPriorityQueue, except poll, which is forwarded to pollMax. That way we can benchmark
   * pollMax using the same code that benchmarks poll.
   */
  static final class InvertedMinMaxPriorityQueue<T> extends ForwardingQueue<T> {
    MinMaxPriorityQueue<T> mmHeap;

    public InvertedMinMaxPriorityQueue(Comparator<T> comparator) {
      mmHeap = MinMaxPriorityQueue.orderedBy(comparator).create();
    }

    @Override

     * UnIterableQueue.iterator().
     */
    assertEquals(5, consumingIterator.next().intValue());
  }

  private static class UnIterableQueue<T> extends ForwardingQueue<T> {
    private final Queue<T> queue;

    UnIterableQueue(Queue<T> queue) {
      this.queue = queue;
    }

    @Override
    public Iterator<T> iterator() {

     * UnIterableQueue.iterator().
     */
    assertEquals(5, consumingIterator.next().intValue());
  }

  private static class UnIterableQueue<T> extends ForwardingQueue<T> {
    private final Queue<T> queue;

    UnIterableQueue(Queue<T> queue) {
      this.queue = queue;
    }

    @Override
    public Iterator<T> iterator() {