extends AbstractMultimapTester<K, V, Multimap<K, V>> {

  @MapFeature.Require({SUPPORTS_PUT, SUPPORTS_REMOVE, ALLOWS_NULL_VALUES})
  public void testReplaceValuesWithNullValue() {
    List<V> values = Arrays.asList(v0(), null, v3());
    multimap().replaceValues(k0(), values);
    assertGet(k0(), values);
  }

  @MapFeature.Require({SUPPORTS_PUT, SUPPORTS_REMOVE, ALLOWS_NULL_KEYS})
  public void testReplaceValuesWithNullKey() {

    assertEquals("multiset.count(missing) didn't return 0", 0, getMultiset().count(e3()));
  }

  @CollectionSize.Require(absent = ZERO)
  public void testCount_1() {
    assertEquals("multiset.count(present) didn't return 1", 1, getMultiset().count(e0()));
  }

  @CollectionSize.Require(SEVERAL)
  public void testCount_3() {
    initThreeCopies();

    assertEquals("multiset.count(missing) didn't return 0", 0, getMultiset().count(e3()));
  }

  @CollectionSize.Require(absent = ZERO)
  public void testCount_1() {
    assertEquals("multiset.count(present) didn't return 1", 1, getMultiset().count(e0()));
  }

  @CollectionSize.Require(SEVERAL)
  public void testCount_3() {
    initThreeCopies();

    expectMissing(e3());
  }

  @CollectionFeature.Require(absent = SUPPORTS_ADD)
  @CollectionSize.Require(absent = ZERO)
  public void testAdd_unsupportedPresent() {
    try {
      assertFalse("add(present) should return false or throw", collection.add(e0()));
    } catch (UnsupportedOperationException tolerated) {
    }
    expectUnchanged();
  }

  @CollectionFeature.Require(
      value = {SUPPORTS_ADD, ALLOWS_NULL_VALUES},

  @CollectionFeature.Require(SUPPORTS_ADD)
  public void testElementSetReflectsAddAbsent() {
    Set<E> elementSet = getMultiset().elementSet();
    assertFalse(elementSet.contains(e3()));
    getMultiset().add(e3(), 4);
    assertTrue(elementSet.contains(e3()));
  }

  @CollectionSize.Require(absent = ZERO)
  @CollectionFeature.Require(SUPPORTS_REMOVE)
  public void testElementSetReflectsRemove() {

  @CollectionFeature.Require(SUPPORTS_ADD)
  @CollectionSize.Require(absent = ZERO)
  public void testAdd_supportedPresent() {
    assertTrue("add(present) should return true", getList().add(e0()));
    expectAdded(e0());
  }

  @CollectionFeature.Require(absent = SUPPORTS_ADD)
  @CollectionSize.Require(absent = ZERO)
  /*
   * absent = ZERO isn't required, since unmodList.add() must

  @CollectionFeature.Require(SUPPORTS_ADD)
  @CollectionSize.Require(absent = ZERO)
  public void testAddAll_supportedAllPresent() {
    assertTrue(
        "addAll(allPresent) should return true", getList().addAll(MinimalCollection.of(e0())));
    expectAdded(e0());
  }

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

                  throw new AssertionFailedError(
                      "Should not call merge function if key was absent");
                }));
    expectAdded(e3());
  }

  @MapFeature.Require({SUPPORTS_PUT, ALLOWS_NULL_VALUES})
  @CollectionSize.Require(absent = ZERO)
  public void testMappedToNull() {
    initMapWithNullValue();
    assertEquals(
        "Map.merge(keyMappedToNull, value, function) should return value",
        v3(),

    }
  }

  @CollectionFeature.Require(ALLOWS_NULL_VALUES)
  @CollectionSize.Require(absent = ZERO)
  public void testSpliteratorNullable() {
    initCollectionWithNullElement();
    synchronized (collection) { // for Collections.synchronized
      assertFalse(collection.spliterator().hasCharacteristics(Spliterator.NONNULL));
    }
  }

  @CollectionFeature.Require(SUPPORTS_ADD)

public class SetAddAllTester<E> extends AbstractSetTester<E> {
  @CollectionFeature.Require(SUPPORTS_ADD)
  @CollectionSize.Require(absent = ZERO)
  public void testAddAll_supportedSomePresent() {
    assertTrue(
        "add(somePresent) should return true", getSet().addAll(MinimalCollection.of(e3(), e0())));
    expectAdded(e3());
  }

  @CollectionFeature.Require(SUPPORTS_ADD)
  public void testAddAll_withDuplicates() {