this.factory = factory;
      this.characteristics = characteristics;
      this.estimatedSize = estimatedSize;
    }

    /*
     * The tryAdvance and forEachRemaining in FlatMapSpliteratorOfPrimitive are overloads of these
     * methods, not overrides. They are annotated @Override because they implement methods from
     * Spliterator.OfPrimitive (and override default implementations from Spliterator.OfPrimitive or