private Sorter createSorter() {
      final List<ItemPoolSorter<InventoryItem>> oneColSorters =
          new ArrayList<ItemPoolSorter<InventoryItem>>(maxSortDepth);

      for (final ItemColumn col : this.colsToSort) {
        oneColSorters.add(
            new ItemPoolSorter<InventoryItem>(
                col.getFnSort(),
                col.getConfig().getSortState().equals(SortState.ASC) ? true : false));
      }

      return new Sorter(oneColSorters);
    }