assertFalse(multimap.containsKey("cat"));
    assertTrue(multimap.containsValue(1));
    assertFalse(multimap.containsValue(5));
    assertTrue(multimap.containsEntry("foo", 1));
    assertFalse(multimap.containsEntry("cat", 1));
    assertFalse(multimap.containsEntry("foo", 5));
    assertFalse(multimap.entries().isEmpty());
    assertEquals(3, multimap.size());
    assertFalse(multimap.isEmpty());

    assertFalse(multimap.containsKey("cat"));
    assertTrue(multimap.containsValue(1));
    assertFalse(multimap.containsValue(5));
    assertTrue(multimap.containsEntry("foo", 1));
    assertFalse(multimap.containsEntry("cat", 1));
    assertFalse(multimap.containsEntry("foo", 5));
    assertFalse(multimap.entries().isEmpty());
    assertEquals(3, multimap.size());
    assertFalse(multimap.isEmpty());

    assertFalse(multimap.containsKey("cat"));
    assertTrue(multimap.containsValue(1));
    assertFalse(multimap.containsValue(5));
    assertTrue(multimap.containsEntry("foo", 1));
    assertFalse(multimap.containsEntry("cat", 1));
    assertFalse(multimap.containsEntry("foo", 5));
    assertFalse(multimap.entries().isEmpty());
    assertEquals(3, multimap.size());
    assertFalse(multimap.isEmpty());

    assertFalse(multimap.containsKey("cat"));
    assertTrue(multimap.containsValue(1));
    assertFalse(multimap.containsValue(5));
    assertTrue(multimap.containsEntry("foo", 1));
    assertFalse(multimap.containsEntry("cat", 1));
    assertFalse(multimap.containsEntry("foo", 5));
    assertFalse(multimap.entries().isEmpty());
    assertEquals(3, multimap.size());
    assertFalse(multimap.isEmpty());

    }

    @Override
    public boolean contains(@CheckForNull Object object) {
      if (object instanceof Entry) {
        Entry<?, ?> entry = (Entry<?, ?>) object;
        return multimap.containsEntry(entry.getKey(), entry.getValue());
      }
      return false;
    }

    @Override
    public int size() {
      return multimap.size();
    }

    @Override

      synchronized (mutex) {
        return delegate().containsValue(value);
      }
    }

    @Override
    public boolean containsEntry(@CheckForNull Object key, @CheckForNull Object value) {
      synchronized (mutex) {
        return delegate().containsEntry(key, value);
      }
    }

    @Override
    public Collection<V> get(@ParametricNullness K key) {
      synchronized (mutex) {

    Multimap<String, Integer> mod = HashMultimap.create();
    Multimap<String, Integer> unmod = Multimaps.unmodifiableMultimap(mod);
    assertEquals(mod, unmod);
    mod.put("foo", 1);
    assertTrue(unmod.containsEntry("foo", 1));
    assertEquals(mod, unmod);
  }

  @SuppressWarnings("unchecked")
  public void testUnmodifiableMultimapEntries() {
    Multimap<String, Integer> mod = HashMultimap.create();

    }

    @Override
    public boolean containsValue(@CheckForNull Object value) {
      return map.containsValue(value);
    }

    @Override
    public boolean containsEntry(@CheckForNull Object key, @CheckForNull Object value) {
      return map.entrySet().contains(Maps.immutableEntry(key, value));
    }

    @Override
    public Set<V> get(@ParametricNullness final K key) {

   * ImmutableSet<Color> allColors = ImmutableSet.of(red, green, blue);
   *
   * ImmutableMap<String, Color> colorForName =
   *     uniqueIndex(allColors, c -> c.toString());
   * assertThat(colorForName).containsEntry("red", red);
   * }</pre>
   *
   * <p>If your index may associate multiple values with each key, use {@link
   * Multimaps#index(Iterable, Function) Multimaps.index}.
   *

    Multimap<String, Integer> mod = HashMultimap.create();
    Multimap<String, Integer> unmod = Multimaps.unmodifiableMultimap(mod);
    assertEquals(mod, unmod);
    mod.put("foo", 1);
    assertTrue(unmod.containsEntry("foo", 1));
    assertEquals(mod, unmod);
  }

  @SuppressWarnings("unchecked")
  public void testUnmodifiableMultimapEntries() {
    Multimap<String, Integer> mod = HashMultimap.create();