Java Sort List

....
versionItemList = em.createQuery(mySQL).getResultList();
Collections.sort(versionItemList, new VersionItemComparator());
....

class VersionItemComparator implements Comparator{

    @Override
    public int compare(VersionItem item1, VersionItem item2){

         return item1.getPositionID().compareTo(item2.getPositionID());

    }