List<Schedule> prevSchedules = htl.find("from Schedule where position = ?", schedule.getPosition() - 1);
if (prevSchedules.size() > 0)
{
prevSchedules.get(0).setPosition(schedule.getPosition());
htl.update(prevSchedules.get(0));
}
schedule.setPosition(schedule.getPosition() - 1);
htl.update(schedule);