return new StandardElementSet();
    }

    @Override
    public Iterator<T> iterator() {
      return standardIterator();
    }

    @Override
    public boolean isEmpty() {
      return standardIsEmpty();
    }

    @Override
    public int size() {
      return standardSize();
    }
  }

  public static Test suite() {
    TestSuite suite = new TestSuite();

     * @throws IllegalArgumentException if duplicate keys were added
     */
    public ImmutableClassToInstanceMap<B> build() {
      ImmutableMap<Class<? extends B>, B> map = mapBuilder.buildOrThrow();
      if (map.isEmpty()) {
        return of();
      } else {
        return new ImmutableClassToInstanceMap<>(map);
      }
    }
  }

  /**

  @CollectionFeature.Require(SUPPORTS_REMOVE)
  public void testEntrySet_clear() {
    getMultiset().entrySet().clear();
    assertTrue("multiset not empty after entrySet().clear()", getMultiset().isEmpty());
  }

  @CollectionSize.Require(ONE)
  @CollectionFeature.Require(SUPPORTS_ITERATOR_REMOVE)
  public void testEntrySet_iteratorRemovePropagates() {

    GeneralRange<Integer> range = GeneralRange.range(ORDERING, 2, OPEN, 4, CLOSED);
    assertTrue(range.intersect(GeneralRange.range(ORDERING, 5, CLOSED, 6, CLOSED)).isEmpty());
    assertTrue(range.intersect(GeneralRange.range(ORDERING, 1, OPEN, 2, OPEN)).isEmpty());
  }

  public void testFromRangeAll() {
    assertEquals(GeneralRange.all(Ordering.natural()), GeneralRange.from(Range.all()));
  }

    Set<MethodSignature> found = getAllFauxveridden(descendant, ancestor);
    Set<MethodSignature> missing = ImmutableSortedSet.copyOf(difference(required, found));
    if (!missing.isEmpty()) {
      fail(
          rootLocaleFormat(
              "%s should hide the public static methods declared in %s: %s",
              descendant.getSimpleName(), ancestor.getSimpleName(), missing));
    }
  }

      failed = this.failed
      code = receivedCloseCode
      reason = receivedCloseReason

      readerToClose = reader
      reader = null

      if (enqueuedClose && messageAndCloseQueue.isEmpty()) {
        // Close the writer on the writer's thread.
        val writerToClose = this.writer
        if (writerToClose != null) {
          this.writer = null

    return new EntrySet();
  }

  @Override
  int distinctElements() {
    return countMap.size();
  }

  @Override
  public boolean isEmpty() {
    return countMap.isEmpty();
  }

  @Override
  Iterator<Entry<E>> entryIterator() {
    // AbstractIterator makes this fairly clean, but it doesn't support remove(). To support

  }

  @Override
  public @Nullable K higherKey(K key) {
    return delegate.higherKey(checkValid(key));
  }

  @Override
  public boolean isEmpty() {
    return delegate.isEmpty();
  }

  @Override
  public NavigableSet<K> keySet() {
    return navigableKeySet();
  }

  @Override
  public @Nullable Entry<K, V> lastEntry() {

  }

  @Override
  public boolean isEmpty() {
    return false;
  }

  @Override
  @SuppressWarnings("unchecked") // TODO(cpovirk): Use a shared unsafeCompare method.
  public ContiguousSet<C> intersection(ContiguousSet<C> other) {
    checkNotNull(other);
    checkArgument(this.domain.equals(other.domain));
    if (other.isEmpty()) {
      return other;
    } else {

  }

  @CollectionFeature.Require(SUPPORTS_REMOVE)
  @CollectionSize.Require(ONE)
  public void testSingletonSetPollFirst() {
    assertEquals(a, navigableSet.pollFirst());
    assertTrue(navigableSet.isEmpty());
  }

  @CollectionSize.Require(ONE)
  public void testSingletonSetNearby() {
    assertNull(navigableSet.lower(e0()));
    assertEquals(a, navigableSet.floor(e0()));