}

  @MapFeature.Require(absent = ALLOWS_NULL_VALUE_QUERIES)
  public void testContains_nullNotContainedAndUnsupported() {
    expectNullValueMissingWhenNullValuesUnsupported(
        "containsValue(null) should return false or throw");
  }

  @MapFeature.Require(ALLOWS_NULL_VALUES)
  @CollectionSize.Require(absent = ZERO)
  public void testContains_nonNullWhenNullContained() {

    new EqualsTester()
        .addEqualityGroup(multimap())
        .addEqualityGroup(getSubjectGenerator().create(targetEntries.toArray()))
        .testEquals();
  }

  @CollectionSize.Require(absent = ZERO)
  @MapFeature.Require(ALLOWS_NULL_KEYS)
  public void testEqualsMultimapWithNullKey() {
    Multimap<K, V> original = multimap();
    initMultimapWithNullKey();
    Multimap<K, V> withNull = multimap();
    new EqualsTester()

@SuppressWarnings("JUnit4ClassUsedInJUnit3")
public class QueueElementTester<E> extends AbstractQueueTester<E> {
  @CollectionSize.Require(ZERO)
  public void testElement_empty() {
    assertThrows(NoSuchElementException.class, () -> getQueue().element());
    expectUnchanged();
  }

  @CollectionSize.Require(ONE)
  public void testElement_size1() {
    assertEquals("size1Queue.element() should return first element", e0(), getQueue().element());

        collection.containsAll(MinimalCollection.of(e3())));
  }

  @CollectionFeature.Require(absent = ALLOWS_NULL_QUERIES)
  public void testContainsAll_nullNotAllowed() {
    try {
      assertFalse(collection.containsAll(MinimalCollection.of((E) null)));
    } catch (NullPointerException tolerated) {
    }
  }

  @CollectionFeature.Require(ALLOWS_NULL_QUERIES)
  public void testContainsAll_nullAllowed() {

    assertEquals("Different ordered iteration", expected, iteratorElements);
  }

  @CollectionFeature.Require(ALLOWS_NULL_VALUES)
  @CollectionSize.Require(absent = ZERO)
  public void testIterator_nullElement() {
    initCollectionWithNullElement();
    List<E> iteratorElements = new ArrayList<>();
    for (E element : collection) { // uses iterator()
      iteratorElements.add(element);
    }

  @CollectionFeature.Require(ALLOWS_NULL_VALUES)
  @CollectionSize.Require(absent = ZERO)
  public void testCreateWithNull_supported() {
    E[] array = createArrayWithNullElement();
    collection = getSubjectGenerator().create(array);
    expectContents(array);
  }

  @CollectionFeature.Require(absent = ALLOWS_NULL_VALUES)
  @CollectionSize.Require(absent = ZERO)

public class SetAddTester<E> extends AbstractSetTester<E> {
  @CollectionFeature.Require(SUPPORTS_ADD)
  @CollectionSize.Require(absent = ZERO)
  public void testAdd_supportedPresent() {
    assertFalse("add(present) should return false", getSet().add(e0()));
    expectUnchanged();
  }

  @CollectionFeature.Require(value = {SUPPORTS_ADD, ALLOWS_NULL_VALUES})
  @CollectionSize.Require(absent = ZERO)
  public void testAdd_supportedNullPresent() {

@SuppressWarnings("JUnit4ClassUsedInJUnit3")
public class ListReplaceAllTester<E> extends AbstractListTester<E> {
  @ListFeature.Require(SUPPORTS_SET)
  public void testReplaceAll() {
    getList().replaceAll(e -> samples.e3());
    expectContents(nCopies(getNumElements(), samples.e3()));
  }

  @ListFeature.Require(SUPPORTS_SET)
  public void testReplaceAll_changesSome() {
    getList().replaceAll(e -> e.equals(samples.e0()) ? samples.e3() : e);

        "A Set should not equal another Set containing different elements.",
        getSet().equals(MinimalSet.from(elements)));
  }

  @CollectionSize.Require(absent = CollectionSize.ZERO)
  @CollectionFeature.Require(ALLOWS_NULL_VALUES)
  public void testEquals_containingNull() {
    Collection<E> elements = getSampleElements(getNumElements() - 1);
    elements.add(null);

    collection = getSubjectGenerator().create(elements.toArray());

  }

  @CollectionSize.Require(absent = CollectionSize.ZERO)
  public void testEquals_otherListContainingNull() {
    List<E> other = new ArrayList<>(getSampleElements());
    other.set(other.size() / 2, null);
    assertFalse(
        "Two Lists should not be equal if exactly one of them has null at a given index.",
        getList().equals(other));
  }

  @CollectionSize.Require(absent = CollectionSize.ZERO)