code: public static IteratorFromReaderFactory<String> getFactory(String tag) {
      return new XMLBeginEndIterator.XMLBeginEndIteratorFactory<String>(tag, new IdentityFunction<String>(), false, false);
    }
docs: Returns a factory that vends BeginEndIterators that reads the contents of
  the given Reader, extracts text between the specified Strings, then
  returns the result.
  
  @param tag The tag the XMLBeginEndIterator will match on
  @return The IteratorFromReaderFactory