public void addSort(final CriteriaSort sort) {
        if (sortList == null) {
            sortList = new ArrayList<>();
        }
        sortList.add(sort);
    }
Base criteria object used to aid getting pages of data.
stroom-legacy/stroom-legacy-model_6_1/src/main/java/stroom/legacy/model_6_1/BaseCriteria.java