Java SSH Hibernate经过代码实现从数据库中随机取出指定条数的随机数据

/**
	 * 根据提供的数量获取随机的问题列表
	 * @param totel
	 * @return
	 */
	public List getRadomQuestionList(final Integer tot){
		List res = null;
		final Integer totel = tot == null ? new Integer(1) : tot;		
		res = baseDao.getHibernateTemplate().executeFind(new HibernateCallback() {
			public Object doInHibernate(Session s) {
				Criteria c = s.createCriteria(Question.class);
				int resSize =c.list().size();
				Random r=new Random(); 
				int n = resSize - totel.intValue();
			    return c.setFirstResult(r.nextInt(n)+1).setMaxResults(totel.intValue()).list(); 
			}
		});
		if(null != res && res.size() > 0){
			for (int i = 0; i < res.size(); i++) {
				Question ques = (Question)res.get(i);
				ques = this.getRadomQuestionAndAnswerByQuestion(ques);
			}
		}
		return res;
	}