Interface IBytesRefIterator

Return the BytesRef Comparer used to sort terms provided by the iterator. This may return null if there are no items or the iterator is not sorted. Callers may invoke this method many times, so it's best to cache a single instance & reuse it.

Increments the iteration to the next BytesRef in the iterator. Returns the resulting BytesRef or null if the end of the iterator is reached. The returned BytesRef may be re-used across calls to Next(). After this method returns null, do not call it again: the results are undefined.