@CanIgnoreReturnValue
    @CheckForNull
    V refresh(K key, int hash, CacheLoader<? super K, V> loader, boolean checkTime) {
      final LoadingValueReference<K, V> loadingValueReference =
          insertLoadingValueReference(key, hash, checkTime);
      if (loadingValueReference == null) {
        return null;
      }

      ListenableFuture<V> result = loadAsync(key, hash, loadingValueReference, loader);

    @CanIgnoreReturnValue
    @CheckForNull
    V refresh(K key, int hash, CacheLoader<? super K, V> loader, boolean checkTime) {
      final LoadingValueReference<K, V> loadingValueReference =
          insertLoadingValueReference(key, hash, checkTime);
      if (loadingValueReference == null) {
        return null;
      }

      ListenableFuture<V> result = loadAsync(key, hash, loadingValueReference, loader);