map.put(key, value);
      if (value != 0L) {
        nonZeroKeys.add(key);
      }
    }
    assertEquals(ITERATIONS, map.size());
    assertTrue(map.asMap().containsValue(0L));

    map.removeAllZeros();
    assertFalse(map.asMap().containsValue(0L));
    assertEquals(ITERATIONS / 2, map.size());
    assertEquals(nonZeroKeys, map.asMap().keySet());
  }

  public void testClear() {

    Multimap<String, Integer> multimap = createMultimap();
    assertTrue(multimap.containsKey("foo"));
    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));

    }

    @Override
    public boolean containsKey(final Object key) {
        return getProperties().containsKey(key);
    }

    @Override
    public boolean containsValue(final Object value) {
        return getProperties().containsValue(value);
    }

    @Override
    public Enumeration<Object> elements() {
        return getProperties().elements();
    }

    @Override

    Multimap<String, Integer> multimap = createMultimap();
    assertTrue(multimap.containsKey("foo"));
    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));

  }

  // accessors

  @Override
  public boolean containsKey(@Nullable Object key) {
    return map.containsKey(key);
  }

  @Override
  public boolean containsValue(@Nullable Object value) {
    return value != null && super.containsValue(value);
  }

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

  // views

  /**

  }

  // accessors

  @Override
  public boolean containsKey(@Nullable Object key) {
    return map.containsKey(key);
  }

  @Override
  public boolean containsValue(@Nullable Object value) {
    return value != null && super.containsValue(value);
  }

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

  // views

  /**

      return backingMap;
    }

    @Override
    public boolean containsKey(Object key) {
      return standardContainsKey(key);
    }

    @Override
    public boolean containsValue(Object value) {
      return standardContainsValue(value);
    }

    @Override
    public void putAll(Map<? extends K, ? extends V> map) {
      standardPutAll(map);
    }

    @Override

    return wrappedHashMapTests(
        new WrappedHashMapGenerator() {
          @Override
          Map<String, String> wrap(HashMap<String, String> map) {
            if (map.containsValue(null)) {
              throw new NullPointerException();
            }

            return new AbstractMap<String, String>() {
              @Override
              public Set<Entry<String, String>> entrySet() {

    return null;
  }

  @Override
  public boolean containsKey(Object key) {
    return cachingHashMap.containsKey(key) && !isExpired(cachingHashMap.get(key));
  }

  @Override
  public boolean containsValue(Object value) {
    for (Timestamped<V> val : cachingHashMap.values()) {
      if (val.getValue().equals(value)) {
        if (!isExpired(val)) {
          return true;
        }
      }
    }

    return wrappedHashMapTests(
        new WrappedHashMapGenerator() {
          @Override
          Map<String, String> wrap(HashMap<String, String> map) {
            if (map.containsValue(null)) {
              throw new NullPointerException();
            }

            return new AbstractMap<String, String>() {
              @Override
              public Set<Entry<String, String>> entrySet() {