* #entrySet}.
   */
  @Override
  public ImmutableSet<V> values() {
    return inverse().keySet();
  }

  @Override
  final ImmutableSet<V> createValues() {
    throw new AssertionError("should never be called");
  }

  /**
   * Guaranteed to throw an exception and leave the bimap unmodified.
   *
   * @throws UnsupportedOperationException always
   * @deprecated Unsupported operation.