*/
  public static <
          V1 extends @Nullable Object, V2 extends @Nullable Object, V3 extends @Nullable Object>
      Combiner3<V1, V2, V3> whenAllSucceed(
          ClosingFuture<V1> future1, ClosingFuture<V2> future2, ClosingFuture<V3> future3) {
    return new Combiner3<>(future1, future2, future3);
  }

  /**

    nullKeyEntry = entry(null, v3());
    nullValueEntry = entry(k3(), null);
    nullKeyValueEntry = entry(null, null);
    presentKeyNullValueEntry = entry(k0(), null);
  }

  @MapFeature.Require(SUPPORTS_PUT)
  @CollectionSize.Require(absent = ZERO)
  public void testPut_supportedPresent() {
    assertEquals("put(present, value) should return the old value", v0(), getMap().put(k0(), v3()));
    expectReplacement(entry(k0(), v3()));

    assertTrue(result.add(v3()));
    assertTrue(multimap().containsKey(k0()));
    assertEquals(getNumElements() + 1, multimap().size());
    assertTrue(multimap().containsEntry(k0(), v3()));
  }

  @MapFeature.Require(SUPPORTS_PUT)
  public void testPropagatesAddAllToMultimap() {
    Collection<V> result = multimap().get(k0());
    assertTrue(result.addAll(singletonList(v3())));

  @MapFeature.Require(SUPPORTS_PUT)
  @CollectionSize.Require(absent = ZERO)
  public void testReplaceEntry_supportedPresent() {
    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)

  }

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

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

  @CollectionSize.Require(absent = ZERO)
  public void testContainsEntryYes() {
    assertTrue(multimap().containsEntry(k0(), v0()));
  }

  public void testContainsEntryNo() {
    assertFalse(multimap().containsEntry(k3(), v3()));
  }

  public void testContainsEntryAgreesWithGet() {
    for (K k : sampleKeys()) {
      for (V v : sampleValues()) {
        assertEquals(multimap().get(k).contains(v), multimap().containsEntry(k, v));
      }

   */
  public static <
          V1 extends @Nullable Object, V2 extends @Nullable Object, V3 extends @Nullable Object>
      Combiner3<V1, V2, V3> whenAllSucceed(
          ClosingFuture<V1> future1, ClosingFuture<V2> future2, ClosingFuture<V3> future3) {
    return new Combiner3<>(future1, future2, future3);
  }

  /**

    assertEquals(
        "computeIfAbsent(notPresent, function) should return new value",
        v3(),
        getMap()
            .computeIfAbsent(
                k3(),
                k -> {
                  assertEquals(k3(), k);
                  return v3();
                }));
    expectAdded(e3());
  }

  @MapFeature.Require(SUPPORTS_PUT)
  @CollectionSize.Require(absent = ZERO)

      K k1, V v1, K k2, V v2, K k3, V v3) {
    return new Builder<K, V>(Ordering.natural()).put(k1, v1).put(k2, v2).put(k3, v3).build();
  }

  public static <K extends Comparable<? super K>, V> ImmutableSortedMap<K, V> of(
      K k1, V v1, K k2, V v2, K k3, V v3, K k4, V v4) {
    return new Builder<K, V>(Ordering.natural())
        .put(k1, v1)
        .put(k2, v2)
        .put(k3, v3)
        .put(k4, v4)
        .build();

    try {
      getMap().putIfAbsent(k0(), v3());
    } catch (UnsupportedOperationException tolerated) {
    }
    expectUnchanged();
  }

  @MapFeature.Require(value = SUPPORTS_PUT, absent = ALLOWS_NULL_KEYS)
  public void testPutIfAbsent_nullKeyUnsupported() {
    assertThrows(NullPointerException.class, () -> getMap().putIfAbsent(null, v3()));
    expectUnchanged();