private void checkExistingSchedule(String sched_id) throws Exception {
    	ScheduleModel sched = DataStore.getSchedule(sched_id);
		if(sched==null)
			throw new Exception("Cette rencontre n'existe pas.");
		else
			if(sched.isSched_isStart())
				throw new Exception("Cette rencontre a déjà commencé.");
		
	}