* IllegalArgumentException if this is a Cache type that doesn't have a LocalCache.
   */
  static <K, V> LocalCache<K, V> toLocalCache(Cache<K, V> cache) {
    if (cache instanceof LocalLoadingCache) {
      return ((LocalLoadingCache<K, V>) cache).localCache;
    }
    throw new IllegalArgumentException(
        "Cache of type " + cache.getClass() + " doesn't have a LocalCache.");
  }

  /**

   * IllegalArgumentException if this is a Cache type that doesn't have a LocalCache.
   */
  static <K, V> LocalCache<K, V> toLocalCache(Cache<K, V> cache) {
    if (cache instanceof LocalLoadingCache) {
      return ((LocalLoadingCache<K, V>) cache).localCache;
    }
    throw new IllegalArgumentException(
        "Cache of type " + cache.getClass() + " doesn't have a LocalCache.");
  }

  /**