return (fromSplit != null) ? map(fromSplit, characteristics, function) : null;
      }

      @Override
      public long estimateSize() {
        return fromSpliterator.estimateSize();
      }

      @Override
      public int characteristics() {
        int backingCharacteristics = fromSpliterator.characteristics();
        // the following are inherently inherited:

          long topSize) {
    checkArgument(
        (topCharacteristics & Spliterator.SUBSIZED) == 0,
        "flatMap does not support SUBSIZED characteristic");
    checkArgument(
        (topCharacteristics & Spliterator.SORTED) == 0,
        "flatMap does not support SORTED characteristic");
    checkNotNull(fromSpliterator);
    checkNotNull(function);
    return new FlatMapSpliteratorOfObject<>(

      }
    }
  }

  /**
   * Test for 2-bit characteristics. A characteristic is a delta in the input which is repeated in
   * the output. For example, if f() is a block cipher and c is a characteristic, then f(x^c) =
   * f(x)^c with greater than expected probability. The test for funneling is merely a test for
   * 1-bit characteristics.
   *

 *       always returns zero could be called a hash function. It is not.)
 * </ul>
 *
 * <p>Summarizing the last two points: "equal yield equal <i>always</i>; unequal yield unequal
 * <i>often</i>." This is the most important characteristic of all hash functions.
 *
 * <h3>Desirable properties</h3>
 *
 * <p>A high-quality hash function strives for some subset of the following virtues:
 *
 * <ul>

      splitrsBuilder.add(splitr);
      characteristics &= splitr.characteristics();
      estimatedSize = LongMath.saturatedAdd(estimatedSize, splitr.estimateSize());
    }
    return StreamSupport.stream(
            CollectSpliterators.flatMap(
                splitrsBuilder.build().spliterator(),
                splitr -> (Spliterator<T>) splitr,
                characteristics,
                estimatedSize),

    abstract boolean tryAdvance(Consumer<? super E> action);

    abstract @Nullable GeneralSpliterator<E> trySplit();

    final int characteristics() {
      return spliterator.characteristics();
    }

    final long estimateSize() {
      return spliterator.estimateSize();
    }

    final @Nullable Comparator<? super E> getComparator() {

    abstract boolean tryAdvance(Consumer<? super E> action);

    abstract @Nullable GeneralSpliterator<E> trySplit();

    final int characteristics() {
      return spliterator.characteristics();
    }

    final long estimateSize() {
      return spliterator.estimateSize();
    }

    final @Nullable Comparator<? super E> getComparator() {

      splitrsBuilder.add(splitr);
      characteristics &= splitr.characteristics();
      estimatedSize = LongMath.saturatedAdd(estimatedSize, splitr.estimateSize());
    }
    return StreamSupport.stream(
            CollectSpliterators.flatMap(
                splitrsBuilder.build().spliterator(),
                splitr -> (Spliterator<T>) splitr,
                characteristics,
                estimatedSize),

    return Collector.of(
        EnumSetAccumulator::new,
        EnumSetAccumulator::add,
        EnumSetAccumulator::combine,
        EnumSetAccumulator::toImmutableSet,
        Collector.Characteristics.UNORDERED);
  }

  @IgnoreJRERequirement // see enclosing class (whose annotation Animal Sniffer ignores here...)
  private static final class EnumSetAccumulator<E extends Enum<E>> {

    return Collector.of(
        EnumSetAccumulator::new,
        EnumSetAccumulator::add,
        EnumSetAccumulator::combine,
        EnumSetAccumulator::toImmutableSet,
        Collector.Characteristics.UNORDERED);
  }

  private static final class EnumSetAccumulator<E extends Enum<E>> {
    @SuppressWarnings({"rawtypes", "unchecked"})