Object newValue = new Object();
        assertSame(entry.getValue(), cache.asMap().replace(entry.getKey(), newValue));
        assertTrue(cache.asMap().replace(entry.getKey(), newValue, entry.getValue()));
        Object newKey = new Object();
        assertNull(cache.asMap().replace(newKey, entry.getValue()));
        assertFalse(cache.asMap().replace(newKey, entry.getValue(), newValue));

      Set<Object> keys = cache.asMap().keySet();
      assertThrows(NullPointerException.class, () -> keys.toArray((Object[]) null));
      checkEmpty(cache);
    }
  }

  public void testKeySet_addNotSupported() {
    for (LoadingCache<Object, Object> cache : caches()) {
      assertThrows(UnsupportedOperationException.class, () -> cache.asMap().keySet().add(1));

      assertThrows(

    ConcurrentMap<Integer, Integer> asMap = cache.asMap();

    cache.put(10, 100);
    cache.put(2, 52);

    asMap.replace(2, 79);
    asMap.replace(3, 60);

    assertEquals(null, cache.getIfPresent(3));
    assertEquals(null, asMap.get(3));

    assertEquals(Integer.valueOf(79), cache.getIfPresent(2));
    assertEquals(Integer.valueOf(79), asMap.get(2));

    asMap.replace(10, 100, 50);

  }

  @Override
  Map<K, Collection<V>> createAsMap() {
    return new AsMap();
  }

  @Override
  Set<K> createKeySet() {
    return asMap().keySet();
  }

  boolean removeEntriesIf(Predicate<? super Entry<K, Collection<V>>> predicate) {
    Iterator<Entry<K, Collection<V>>> entryIterator = unfiltered.asMap().entrySet().iterator();
    boolean changed = false;
    while (entryIterator.hasNext()) {

        Object newValue = new Object();
        assertSame(entry.getValue(), cache.asMap().replace(entry.getKey(), newValue));
        assertTrue(cache.asMap().replace(entry.getKey(), newValue, entry.getValue()));
        Object newKey = new Object();
        assertNull(cache.asMap().replace(newKey, entry.getValue()));
        assertFalse(cache.asMap().replace(newKey, entry.getValue(), newValue));

      try {
        multimap.asMap().get(presentKey).remove(sampleValue);
        fail("asMap().get().remove() succeeded on unmodifiable multimap");
      } catch (UnsupportedOperationException expected) {
      }
      assertMultimapRemainsUnmodified(multimap, originalEntries);

      try {
        multimap.asMap().values().iterator().next().remove(sampleValue);

  }

  @Override
  Map<K, Collection<V>> createAsMap() {
    return new AsMap();
  }

  @Override
  Set<K> createKeySet() {
    return asMap().keySet();
  }

  boolean removeEntriesIf(Predicate<? super Entry<K, Collection<V>>> predicate) {
    Iterator<Entry<K, Collection<V>>> entryIterator = unfiltered.asMap().entrySet().iterator();
    boolean changed = false;
    while (entryIterator.hasNext()) {

    // 1 won't be cached
    assertThat(cache.getUnchecked(1)).isEqualTo(1);
    assertThat(cache.asMap().keySet()).isEmpty();

    CacheTesting.processPendingNotifications(cache);
    assertThat(removalListener.getCount()).isEqualTo(1);

    // 2 will be cached
    assertThat(cache.getUnchecked(2)).isEqualTo(2);
    assertThat(cache.asMap().keySet()).containsExactly(2);

    CacheTesting.processPendingNotifications(cache);

    assertEquals(1, Iterators.size(cache.asMap().entrySet().iterator()));
    assertEquals(1, Iterators.size(cache.asMap().keySet().iterator()));
    assertEquals(1, Iterators.size(cache.asMap().values().iterator()));

    CacheTesting.expireEntries((LoadingCache<?, ?>) cache, EXPIRING_TIME, ticker);

    for (int i = 0; i < 11; i++) {
      assertFalse(cache.asMap().containsKey(KEY_PREFIX + i));
    }

  public void testTreeMultimapAsMapSorted() {
    TreeMultimap<String, Integer> multimap = createPopulate();
    SortedMap<String, Collection<Integer>> asMap = multimap.asMap();
    assertEquals(Ordering.natural(), asMap.comparator());
    assertEquals("foo", asMap.firstKey());
    assertEquals("tree", asMap.lastKey());
    Set<Integer> fooValues = ImmutableSet.of(1, 3, 7);
    Set<Integer> googleValues = ImmutableSet.of(2, 6);