code: @Override
    protected Long stringToBoundary(String boundary, Integer segmentNumber)
        throws IOException {
      if (segmentRegistration.equals(SEGMENT_BOUNDARY_ASC)
          || segmentRegistration.equals(SEGMENT_BOUNDARY_DESC)) {
        if (segmentNumber == null) {
          return Long.valueOf(boundary);
        } else {
          return Math.floorDiv(Long.parseLong(boundary), segmentNumber);
        }
      } else {
        throw new IOException(
            "not available for segmentRegistration " + segmentRegistration);
      }
    }
docs: /*
  (non-Javadoc)
  
  @see
  mtas.codec.util.collector.MtasDataCollector#stringToBoundary(java.lang.
  String, java.lang.Integer)