private Relation compareTo(Context other) {
      if (other == null) return Relation.DIFFERENT;
      HighlightInfo highlightInfo = getHighlightInfo();
      if (!Objects.equals(highlightInfo, other.getHighlightInfo())) return Relation.DIFFERENT;
      return Objects.equals(getElementForQuickDoc(), other.getElementForQuickDoc())
             ? Relation.SAME
             : highlightInfo == null ? Relation.DIFFERENT : Relation.SIMILAR;
    }
private Relation compareTo(Context other)