public void testPoll_empty() {
    assertNull("emptyQueue.poll() should return null", getQueue().poll());
    expectUnchanged();
  }

  @CollectionFeature.Require(SUPPORTS_REMOVE)
  @CollectionSize.Require(ONE)
  public void testPoll_size1() {
    assertEquals("size1Queue.poll() should return first element", e0(), getQueue().poll());
    expectMissing(e0());
  }

  public void testPoll_empty() {
    assertNull("emptyQueue.poll() should return null", getQueue().poll());
    expectUnchanged();
  }

  @CollectionFeature.Require(SUPPORTS_REMOVE)
  @CollectionSize.Require(ONE)
  public void testPoll_size1() {
    assertEquals("size1Queue.poll() should return first element", e0(), getQueue().poll());
    expectMissing(e0());
  }

  @Override
  public boolean offer(@ParametricNullness E o) {
    return delegate().offer(o);
  }

  @CanIgnoreReturnValue // TODO(cpovirk): Consider removing this?
  @Override
  public @Nullable E poll() {
    return delegate().poll();
  }

  @CanIgnoreReturnValue
  @Override
  @ParametricNullness
  public E remove() {
    return delegate().remove();
  }

  @Override
  public @Nullable E peek() {

  @Override
  public boolean offer(@ParametricNullness E o) {
    return delegate().offer(o);
  }

  @CanIgnoreReturnValue // TODO(cpovirk): Consider removing this?
  @Override
  public @Nullable E poll() {
    return delegate().poll();
  }

  @CanIgnoreReturnValue
  @Override
  @ParametricNullness
  public E remove() {
    return delegate().remove();
  }

  @Override
  public @Nullable E peek() {

    return delegate().offer(e, timeout, unit);
  }

  @CanIgnoreReturnValue // TODO(kak): consider removing this
  @Override
  public @Nullable E poll(long timeout, TimeUnit unit) throws InterruptedException {
    return delegate().poll(timeout, unit);
  }

  @Override
  public void put(E e) throws InterruptedException {
    delegate().put(e);
  }

  @Override
  public int remainingCapacity() {

      }
    }
  }

  /**
   * Implementation of the InvertedMinMaxPriorityQueue which forwards all calls to a
   * 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;

      }
    }
  }

  /**
   * Implementation of the InvertedMinMaxPriorityQueue which forwards all calls to a
   * 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;

    @Override
    public boolean offer(E o) {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.offer(o);
    }

    @Override
    public @Nullable E poll() {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.poll();
    }

    @Override
    public E remove() {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.remove();
    }

    @Override

  }

  @Override
  public E take() throws InterruptedException {
    return delegate().take();
  }

  @Override
  public @Nullable E poll(long timeout, TimeUnit unit) throws InterruptedException {
    return delegate().poll(timeout, unit);
  }

  @Override
  public int drainTo(Collection<? super E> c) {
    return delegate().drainTo(c);
  }

  @Override

  }

  @Override
  public E take() throws InterruptedException {
    return delegate().take();
  }

  @Override
  public @Nullable E poll(long timeout, TimeUnit unit) throws InterruptedException {
    return delegate().poll(timeout, unit);
  }

  @Override
  public int drainTo(Collection<? super E> c) {
    return delegate().drainTo(c);
  }

  @Override