Multimap<K, V> synchronizedMultimap(Multimap<K, V> multimap) {
    return Synchronized.multimap(multimap, null);
  }

  /**
   * Returns an unmodifiable view of the specified multimap. Query operations on the returned
   * multimap "read through" to the specified multimap, and attempts to modify the returned
   * multimap, either directly or through the multimap's views, result in an {@code

  }

  static <K extends @Nullable Object, V extends @Nullable Object> Multimap<K, V> multimap(
      Multimap<K, V> multimap, @CheckForNull Object mutex) {
    if (multimap instanceof SynchronizedMultimap || multimap instanceof BaseImmutableMultimap) {
      return multimap;
    }
    return new SynchronizedMultimap<>(multimap, mutex);
  }

  }

  static <K extends @Nullable Object, V extends @Nullable Object> Multimap<K, V> multimap(
      Multimap<K, V> multimap, @CheckForNull Object mutex) {
    if (multimap instanceof SynchronizedMultimap || multimap instanceof BaseImmutableMultimap) {
      return multimap;
    }
    return new SynchronizedMultimap<>(multimap, mutex);
  }

				"application/x-tika-iworks-protected",
				"application/vnd.arastra.swi",
				"application/vnd.audiograph",
				"application/vnd.autopackage",
				"application/vnd.avistar+xml",
				"application/vnd.blueice.multipass",
				"application/vnd.bluetooth.ep.oob",
				"application/vnd.bmi",
				"application/vnd.businessobjects",
				"application/vnd.cab-jscript",
				"application/vnd.canon-cpdl",
				"application/vnd.canon-lips",