Sorting in Query for MySQL database using hibernate
Session session = HibernateUtil.getSessionFactory().getCurrentSession();
            session.beginTransaction();
            List<Task> tasks = (List<Task>)session.createQuery(
"from Task as t where t.user.username = :name order by t.project.key ASC").setString("name", username).list();
            orderByDeliverable(tasks);
            orderByActivity(tasks);



    private void orderByDeliverable(List<Task> tasks) {
       Collections.sort(tasks, new Comparator<Task>(){
          public int compare(Task t1, Task t2) {
             if(t1.getProject().getId() == t2.getProject().getId())
               return t1.getDeliverable().getKey().compareToIgnoreCase(t2.getDeliverable().getKey());
             return 0;
          }
       });
    }

    private void orderByActivity(List<Task> tasks) {
        Collections.sort(tasks, new Comparator<Task>(){
           public int compare(Task t1, Task t2) {
              if(t1.getProject().getId() == t2.getProject().getId())
             if(t1.getDeliverable().getId() == t2.getDeliverable().getId())
                return t1.getActivity().getKey().compareToIgnoreCase(t2.getActivity().getKey());
            return 0;
           }
       });
    }

tasks = (List<Task>)session.createQuery("from Task as t where t.user.username = :name
order by t.project.key ASC, t.deliverable.key ASC, t.activity.key ASC")
.setString("name", username).list();