* @see IntStream#findFirst()
   * @throws NullPointerException if the last element of the stream is null
   */
  public static OptionalInt findLast(IntStream stream) {
    // findLast(Stream) does some allocation, so we might as well box some more
    java.util.Optional<Integer> boxedLast = findLast(stream.boxed());
    return boxedLast.map(OptionalInt::of).orElse(OptionalInt.empty());
  }

  /**

   * @see IntStream#findFirst()
   * @throws NullPointerException if the last element of the stream is null
   */
  public static OptionalInt findLast(IntStream stream) {
    // findLast(Stream) does some allocation, so we might as well box some more
    java.util.Optional<Integer> boxedLast = findLast(stream.boxed());
    return boxedLast.map(OptionalInt::of).orElse(OptionalInt.empty());
  }

  /**