* that callers don't pass an {@link Entry} by mistake.
   */
  protected V get(K key) {
    return getMap().get(key);
  }

  protected final K k0() {
    return e0().getKey();
  }

  protected final V v0() {
    return e0().getValue();
  }

  protected final K k1() {
    return e1().getKey();
  }

    extends AbstractMapTester<K, V> {

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

  static <K extends @Nullable Object, V extends @Nullable Object> Entry<V, K> reverseEntry(
      Entry<K, V> entry) {
    return mapEntry(entry.getValue(), entry.getKey());
  }

  @Override
  protected void expectContents(Collection<Entry<K, V>> expected) {

    extends AbstractMapTester<K, V> {

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

  static <K extends @Nullable Object, V extends @Nullable Object> Entry<V, K> reverseEntry(
      Entry<K, V> entry) {
    return mapEntry(entry.getValue(), entry.getKey());
  }

  @Override
  protected void expectContents(Collection<Entry<K, V>> expected) {

    for (Entry<K, V> entry : getMap().entrySet()) {
      assertThrows(NullPointerException.class, () -> entry.setValue(null));
      expectUnchanged();
    }
  }

  @MapFeature.Require({SUPPORTS_PUT, ALLOWS_NULL_VALUES})
  @CollectionSize.Require(absent = ZERO)
  public void testSetValueNullSupported() {
    for (Entry<K, V> entry : getMap().entrySet()) {
      if (entry.getKey().equals(k0())) {
        entry.setValue(null);

   * that callers don't pass an {@link Entry} by mistake.
   */
  protected V get(K key) {
    return getMap().get(key);
  }

  protected final K k0() {
    return e0().getKey();
  }

  protected final V v0() {
    return e0().getValue();
  }

  protected final K k1() {
    return e1().getKey();
  }

    resetWithHole();
    assertEquals(a, navigableMap.floorEntry(a.getKey()));
    assertEquals(a.getKey(), navigableMap.floorKey(a.getKey()));
    assertEquals(a, navigableMap.floorEntry(b.getKey()));
    assertEquals(a.getKey(), navigableMap.floorKey(b.getKey()));
    assertEquals(c, navigableMap.floorEntry(c.getKey()));
    assertEquals(c.getKey(), navigableMap.floorKey(c.getKey()));
  }

  @CollectionSize.Require(SEVERAL)

    resetWithHole();
    assertEquals(a, navigableMap.floorEntry(a.getKey()));
    assertEquals(a.getKey(), navigableMap.floorKey(a.getKey()));
    assertEquals(a, navigableMap.floorEntry(b.getKey()));
    assertEquals(a.getKey(), navigableMap.floorKey(b.getKey()));
    assertEquals(c, navigableMap.floorEntry(c.getKey()));
    assertEquals(c.getKey(), navigableMap.floorKey(c.getKey()));
  }

  @CollectionSize.Require(SEVERAL)

    for (Entry<K, V> entry : getMap().entrySet()) {
      assertThrows(NullPointerException.class, () -> entry.setValue(null));
      expectUnchanged();
    }
  }

  @MapFeature.Require({SUPPORTS_PUT, ALLOWS_NULL_VALUES})
  @CollectionSize.Require(absent = ZERO)
  public void testSetValueNullSupported() {
    for (Entry<K, V> entry : getMap().entrySet()) {
      if (entry.getKey().equals(k0())) {
        entry.setValue(null);

@SuppressWarnings("JUnit4ClassUsedInJUnit3")
@NullMarked
public class ConcurrentMapPutIfAbsentTester<K, V> extends AbstractMapTester<K, V> {
  @Override
  protected ConcurrentMap<K, V> getMap() {
    return (ConcurrentMap<K, V>) super.getMap();
  }

  @MapFeature.Require(SUPPORTS_PUT)
  public void testPutIfAbsent_supportedAbsent() {
    assertNull("putIfAbsent(notPresent, value) should return null", putIfAbsent(e3()));

    assertFalse(
        "Maps of different sizes should not be equal.", getMap().equals(newHashMap(moreEntries)));
  }

  public void testEquals_list() {
    assertFalse(
        "A List should never equal a Map.", getMap().equals(copyToList(getMap().entrySet())));
  }

  private static <K, V> Map<K, V> newHashMap(