void addResult(String valueData, String detailData) {
    if (value) {
      if (valueData == null) throw new IllegalArgumentException(CLASS + ": valueData may not be null");
      values.add(valueData);
      if (detail) {
        if (detailData == null) throw new IllegalArgumentException(CLASS + ": detailData may not be null");
        details.add(detailData);
      }
    } 
    counter++;
  }