map.put(one, two);
    map.remove(one);
    assertNotified(listener, one, two, RemovalCause.EXPLICIT);

    map.put(two, three);
    map.remove(two, three);
    assertNotified(listener, two, three, RemovalCause.EXPLICIT);

    map.put(three, four);
    Iterator<?> i = map.entrySet().iterator();
    i.next();
    i.remove();
    assertNotified(listener, three, four, RemovalCause.EXPLICIT);

    map.put(one, two);
    map.remove(one);
    assertNotified(listener, one, two, RemovalCause.EXPLICIT);

    map.put(two, three);
    map.remove(two, three);
    assertNotified(listener, two, three, RemovalCause.EXPLICIT);

    map.put(three, four);
    Iterator<?> i = map.entrySet().iterator();
    i.next();
    i.remove();
    assertNotified(listener, three, four, RemovalCause.EXPLICIT);

    }
  }

  @CheckForNull
  @CanIgnoreReturnValue
  @Override
  public V remove(@CheckForNull Object key) {
    if (key == null) {
      return null;
    }
    int hash = hash(key);
    return segmentFor(hash).remove(key, hash);
  }

  @CanIgnoreReturnValue
  @Override
  public boolean remove(@CheckForNull Object key, @CheckForNull Object value) {
    if (key == null || value == null) {

    }

    @Override
    public boolean remove(@CheckForNull Object o) {
      try {
        return super.remove(o);
      } catch (UnsupportedOperationException e) {
        for (Entry<K, V> entry : map().entrySet()) {
          if (Objects.equal(o, entry.getValue())) {
            map().remove(entry.getKey());
            return true;
          }
        }

    }
  }

  @CheckForNull
  @CanIgnoreReturnValue
  @Override
  public V remove(@CheckForNull Object key) {
    if (key == null) {
      return null;
    }
    int hash = hash(key);
    return segmentFor(hash).remove(key, hash);
  }

  @CanIgnoreReturnValue
  @Override
  public boolean remove(@CheckForNull Object key, @CheckForNull Object value) {
    if (key == null || value == null) {

    assertThat(future.isDone()).isFalse();
    assertThat(executedRunnables).isEmpty();
    assertThat(pendingRunnables).hasSize(1);
    pendingRunnables.remove(0).run();
    assertThat(future.isDone()).isTrue();
    assertThat(executedRunnables).containsExactly(runnable);
    assertThat(pendingRunnables).isEmpty();
  }

    assertThat(future.isDone()).isFalse();
    assertThat(executedRunnables).isEmpty();
    assertThat(pendingRunnables).hasSize(1);
    pendingRunnables.remove(0).run();
    assertThat(future.isDone()).isTrue();
    assertThat(executedRunnables).containsExactly(runnable);
    assertThat(pendingRunnables).isEmpty();
  }