* Returns the newly refreshed value associated with {@code key} if it was refreshed inline, or
     * {@code null} if another thread is performing the refresh or if an error occurs during
     * refresh.
     */
    @CanIgnoreReturnValue
    @CheckForNull
    V refresh(K key, int hash, CacheLoader<? super K, V> loader, boolean checkTime) {
      final LoadingValueReference<K, V> loadingValueReference =

     * Returns the newly refreshed value associated with {@code key} if it was refreshed inline, or
     * {@code null} if another thread is performing the refresh or if an error occurs during
     * refresh.
     */
    @CanIgnoreReturnValue
    @CheckForNull
    V refresh(K key, int hash, CacheLoader<? super K, V> loader, boolean checkTime) {
      final LoadingValueReference<K, V> loadingValueReference =

      LocalCache<String, String> cache = makeLocalCache(builder, loader);

      assertThat(cache.getOrLoad("test")).isEqualTo("testLoad");

      ticker.advance(10, MILLISECONDS); // so that the next call will trigger refresh
      assertThat(cache.getOrLoad("test")).isEqualTo("testLoad");
      reloadStarted.await();
      ticker.advance(500, MILLISECONDS); // so that the entry expires during the reload

      LocalCache<String, String> cache = makeLocalCache(builder, loader);

      assertThat(cache.getOrLoad("test")).isEqualTo("testLoad");

      ticker.advance(10, MILLISECONDS); // so that the next call will trigger refresh
      assertThat(cache.getOrLoad("test")).isEqualTo("testLoad");
      reloadStarted.await();
      ticker.advance(500, MILLISECONDS); // so that the entry expires during the reload

    }

/**
 * Tests to see if the SMB resource exists. If the resource refers
 * only to a server, this method determines if the server exists on the
 * network and is advertising SMB services. If this resource refers to
 * a workgroup, this method determines if the workgroup name is valid on
 * the local SMB network. If this <code>SmbFile</code> refers to the root
 * <code>smb1://</code> resource <code>true</code> is always returned. If