}

  @CollectionSize.Require(absent = ZERO)
  @MapFeature.Require(SUPPORTS_REMOVE)
  public void testRemovePresent() {
    assertTrue(multimap().remove(k0(), v0()));

    assertFalse(multimap().containsEntry(k0(), v0()));
    expectMissing(e0());
    assertEquals(getNumElements() - 1, multimap().size());
    assertGet(k0(), ImmutableList.of());
  }

  @CollectionSize.Require(absent = ZERO)

  }

  @CollectionSize.Require(absent = ZERO)
  @MapFeature.Require(SUPPORTS_REMOVE)
  public void testRemovePresent() {
    assertTrue(multimap().remove(k0(), v0()));

    assertFalse(multimap().containsEntry(k0(), v0()));
    expectMissing(e0());
    assertEquals(getNumElements() - 1, multimap().size());
    assertGet(k0(), ImmutableList.of());
  }

  @CollectionSize.Require(absent = ZERO)

    for (Collection<V> collection : asMap().values()) {
      if (collection.contains(value)) {
        return true;
      }
    }

    return false;
  }

  @Override
  public boolean containsEntry(@Nullable Object key, @Nullable Object value) {
    Collection<V> collection = asMap().get(key);
    return collection != null && collection.contains(value);
  }

  @CanIgnoreReturnValue
  @Override

  /**
   * Returns {@code true} if this multimap contains at least one key-value pair with the key {@code
   * key} and the value {@code value}.
   */
  boolean containsEntry(
      @CompatibleWith("K") @Nullable Object key, @CompatibleWith("V") @Nullable Object value);

  // Modification Operations

  /**
   * Stores a key-value pair in this multimap.
   *

    MapSplitter splitter = COMMA_SPLITTER.trimResults().withKeyValueSeparator(Splitter.on("->"));
    Map<String, String> split = splitter.split(" x -> y, z-> a ");
    assertThat(split).containsEntry("x ", " y");
    assertThat(split).containsEntry("z", " a");
  }

    unfiltered.put("badkey", 1);
    Multimap<String, Integer> filtered = filterValues(unfiltered, VALUE_PREDICATE);
    assertEquals(1, filtered.size());
    assertFalse(filtered.containsEntry("foo", 55556));
    assertTrue(filtered.containsEntry("badkey", 1));
  }

  public void testFilterFiltered() {
    Multimap<String, Integer> unfiltered = HashMultimap.create();
    unfiltered.put("foo", 55556);
    unfiltered.put("badkey", 1);

  /**
   * Returns {@code true} if this multimap contains at least one key-value pair with the key {@code
   * key} and the value {@code value}.
   */
  boolean containsEntry(
      @CompatibleWith("K") @Nullable Object key, @CompatibleWith("V") @Nullable Object value);

  // Modification Operations

  /**
   * Stores a key-value pair in this multimap.
   *

    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());

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

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

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

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

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

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