* @param <V> the value type of {@link IdentityHashMap}
     * @return a new instance of {@link IdentityHashMap}
     * @see IdentityHashMap#IdentityHashMap()
     */
    public static <K, V> IdentityHashMap<K, V> newIdentityHashMap() {
        return new IdentityHashMap<>();
    }

    /**
     * Creates and returns a new instance of {@link IdentityHashMap}.
     *
     * @param <K> the key type of {@link IdentityHashMap}

   * way {@code IdentityHashMap} handles key lookups.
   *
   * @since 8.0
   */
  public static <E extends @Nullable Object> Set<E> newIdentityHashSet() {
    return Collections.newSetFromMap(Maps.<E, Boolean>newIdentityHashMap());
  }

  /**
   * Creates an empty {@code CopyOnWriteArraySet} instance.
   *
   * <p><b>Note:</b> if you need an immutable empty {@link Set}, use {@link Collections#emptySet}
   * instead.
   *