@MapFeature.Require(SUPPORTS_PUT)
  public void testPutAddsValueAtEnd() {
    for (K key : sampleKeys()) {
      for (V value : sampleValues()) {
        resetContainer();

        List<V> values = multimap().get(key);
        List<V> expectedValues = copyToList(values);

        assertTrue(multimap().put(key, value));
        expectedValues.add(value);

    assertGet(k0());
    assertEquals(getNumElements() - 1, multimap().size());
  }

  @CollectionSize.Require(SEVERAL)
  @MapFeature.Require(SUPPORTS_PUT)
  public void testAsMapEntrySetReflectsPutSameKey() {
    resetContainer(mapEntry(k0(), v0()), mapEntry(k0(), v3()));

    Set<Entry<K, Collection<V>>> asMapEntrySet = multimap().asMap().entrySet();
    Collection<V> valueCollection = getOnlyElement(asMapEntrySet).getValue();

  @MapFeature.Require(SUPPORTS_PUT)
  public void testPutAddsValueAtEnd() {
    for (K key : sampleKeys()) {
      for (V value : sampleValues()) {
        resetContainer();

        List<V> values = multimap().get(key);
        List<V> expectedValues = copyToList(values);

        assertTrue(multimap().put(key, value));
        expectedValues.add(value);

    for (K key : keys) {
      resetCollection();
      assertTrue(multimap().asMap().remove(key) instanceof Set);
    }
  }

  @CollectionSize.Require(SEVERAL)
  public void testEquals() {
    resetContainer(mapEntry(k0(), v0()), mapEntry(k1(), v0()), mapEntry(k0(), v3()));
    Map<K, Collection<V>> expected = Maps.newHashMap();
    expected.put(k0(), newHashSet(v0(), v3()));
    expected.put(k1(), newHashSet(v0()));

    for (K key : sampleKeys()) {
      resetContainer();
      Collection<V> collection = multimap().get(key);
      multimap().clear();
      assertEmpty(collection);
    }
  }

  @MapFeature.Require(SUPPORTS_REMOVE)
  @CollectionSize.Require(absent = ZERO)
  public void testClearPropagatesToAsMapGet() {
    for (K key : sampleKeys()) {
      resetContainer();

  @Override
  protected Collection<Entry<K, V>> actualContents() {
    return getMap().entrySet();
  }

  /** @see AbstractContainerTester#resetContainer() */
  protected final void resetMap() {
    resetContainer();
  }

  protected void resetMap(Entry<K, V>[] entries) {
    resetContainer(getSubjectGenerator().create((Object[]) entries));
  }

  protected void expectMissingKeys(K... elements) {
    for (K element : elements) {

  @CollectionSize.Require(absent = ZERO)
  public void testRemovePropagatesToGet() {
    List<Entry<K, V>> entries = copyToList(multimap().entries());
    for (Entry<K, V> entry : entries) {
      resetContainer();

      K key = entry.getKey();
      V value = entry.getValue();
      Collection<V> collection = multimap().get(key);
      assertNotNull(collection);

  @CollectionSize.Require(absent = ZERO)
  public void testRemovePropagatesToGet() {
    List<Entry<K, V>> entries = copyToList(multimap().entries());
    for (Entry<K, V> entry : entries) {
      resetContainer();

      K key = entry.getKey();
      V value = entry.getValue();
      Collection<V> collection = multimap().get(key);
      assertNotNull(collection);

  @MapFeature.Require(ALLOWS_NULL_KEYS)
  public void testEquals_containingNullKey() {
    Collection<Entry<K, V>> entries = getSampleEntries(getNumEntries() - 1);
    entries.add(entry(null, v3()));

    resetContainer(getSubjectGenerator().create(entries.toArray()));
    assertTrue(
        "A Map should equal any other Map containing the same entries,"
            + " even if some keys are null.",

    assertEmpty(getResult);
    expectMissing(e0());
  }

  @CollectionSize.Require(SEVERAL)
  @MapFeature.Require(SUPPORTS_REMOVE)
  public void testRemoveAllMultipleValues() {
    resetContainer(mapEntry(k0(), v0()), mapEntry(k0(), v1()), mapEntry(k0(), v2()));

    assertContentsAnyOrder(multimap().removeAll(k0()), v0(), v1(), v2());
    assertEmpty(multimap());
  }

  @CollectionSize.Require(absent = ZERO)