private void recalculateItemsAndGroups(final Comparator<Object> comp) {

        itemsAndGroups.clear();
        itemsAndGroups.addAll(items);
        itemsAndGroups.addAll(groups);
        if (comp != null) {
            Collections.sort(items, comp);
            Collections.sort(groups, comp);
            Collections.sort(itemsAndGroups, comp);
        }
    }
Represents a group of items
<br>
This class is meant to be used to build a tree of groups containing other groups
main/src/main/java/cgeo/geocaching/utils/ItemGroup.java