stream.defaultReadObject();
    expectedValuesPerKey = DEFAULT_VALUES_PER_KEY;
    int distinctKeys = Serialization.readCount(stream);
    Map<K, Collection<V>> map = new HashMap<>();
    setMap(map);
    Serialization.populateMultimap(this, stream, distinctKeys);
  }

  @GwtIncompatible @J2ktIncompatible private static final long serialVersionUID = 0;

  private Entry<K, V> nullKeyEntry;
  private Entry<K, V> nullValueEntry;
  private Entry<K, V> nullKeyValueEntry;
  private Entry<K, V> presentKeyNullValueEntry;

  @Override
  public void setUp() throws Exception {
    super.setUp();
    nullKeyEntry = entry(null, v3());
    nullValueEntry = entry(k3(), null);
    nullKeyValueEntry = entry(null, null);
    presentKeyNullValueEntry = entry(k0(), null);
  }

  private List<Entry<K, V>> containsNullValue;

  @Override
  public void setUp() throws Exception {
    super.setUp();
    containsNullKey = singletonList(entry(null, v3()));
    containsNullValue = singletonList(entry(k3(), null));
  }

  @MapFeature.Require(SUPPORTS_PUT)
  public void testPutAll_supportedNothing() {
    getMap().putAll(emptyMap());
    expectUnchanged();
  }

  private Entry<K, V> nullKeyEntry;
  private Entry<K, V> nullValueEntry;
  private Entry<K, V> nullKeyValueEntry;
  private Entry<K, V> presentKeyNullValueEntry;

  @Override
  public void setUp() throws Exception {
    super.setUp();
    nullKeyEntry = entry(null, v3());
    nullValueEntry = entry(k3(), null);
    nullKeyValueEntry = entry(null, null);
    presentKeyNullValueEntry = entry(k0(), null);
  }

  private List<Entry<K, V>> entries;
  private Entry<K, V> a;
  private Entry<K, V> b;
  private Entry<K, V> c;

  @Override
  public void setUp() throws Exception {
    super.setUp();
    navigableMap = (NavigableMap<K, V>) getMap();
    entries =
        copyToList(
            getSubjectGenerator()
                .getSampleElements(getSubjectGenerator().getCollectionSize().getNumElements()));

  private List<Entry<K, V>> entries;
  private Entry<K, V> a;
  private Entry<K, V> b;
  private Entry<K, V> c;

  @Override
  public void setUp() throws Exception {
    super.setUp();
    navigableMap = (NavigableMap<K, V>) getMap();
    entries =
        copyToList(
            getSubjectGenerator()
                .getSampleElements(getSubjectGenerator().getCollectionSize().getNumElements()));

  private List<Entry<K, V>> containsNullValue;

  @Override
  public void setUp() throws Exception {
    super.setUp();
    containsNullKey = singletonList(entry(null, v3()));
    containsNullValue = singletonList(entry(k3(), null));
  }

  @MapFeature.Require(SUPPORTS_PUT)
  public void testPutAll_supportedNothing() {
    getMap().putAll(emptyMap());
    expectUnchanged();
  }

  private SortedMap<K, V> navigableMap;
  private Entry<K, V> a;
  private Entry<K, V> c;

  @Override
  public void setUp() throws Exception {
    super.setUp();
    navigableMap = (SortedMap<K, V>) getMap();
    List<Entry<K, V>> entries =
        copyToList(
            getSubjectGenerator()

  @Override
  protected ConcurrentMap<K, V> getMap() {
    return (ConcurrentMap<K, V>) super.getMap();
  }

  @MapFeature.Require(SUPPORTS_PUT)
  @CollectionSize.Require(absent = ZERO)
  public void testReplaceEntry_supportedPresent() {
    assertTrue(getMap().replace(k0(), v0(), v3()));
    expectReplacement(entry(k0(), v3()));
  }

    try {
      assertTrue(getMap().replace(k0(), v0(), v3()));
      expectReplacement(entry(k0(), v3()));
    } catch (ClassCastException tolerated) { // for ClassToInstanceMap
      expectUnchanged();
    }
  }

  @MapFeature.Require(SUPPORTS_PUT)
  @CollectionSize.Require(absent = ZERO)
  public void testReplaceEntry_supportedPresentUnchanged() {
    assertTrue(getMap().replace(k0(), v0(), v0()));