docs: public FilterCellSlowStr addNewCell(String newValue) {
          if (!newValue.equals(FilterListSlowStr.wildCard)) {
              if (nextCell == null) {
                  nextCell = new HashMap<String, FilterCellSlowStr>();
              }
  
              FilterCellSlowStr newCell = new FilterCellSlowStr();
              nextCell.put(newValue, newCell);
              return newCell;
          }
          if (wildcardCell == null) {
              wildcardCell = new FilterCellSlowStr();
          }
          return wildcardCell;
      }