Predicate<? super K> keyPredicate) {
    return compose(keyPredicate, Maps.<K>keyFunction());
  }

  static <V extends @Nullable Object> Predicate<Entry<?, V>> valuePredicateOnEntries(
      Predicate<? super V> valuePredicate) {
    return compose(valuePredicate, Maps.<V>valueFunction());
  }

  /**