hibernate 保存不重复数据

参考文章
[url]
http://biancheng.dnbcw.info/java/71552.html[/url]

@SuppressWarnings("unchecked")
	public DeviceInfo getDIByImei(String imei){
		ArrayList<DeviceInfo> list = (ArrayList<DeviceInfo>)
		s.createQuery("from DeviceInfo where imei = '"+imei+"'").list();
		DeviceInfo result = null;
		if (list.size()>0) {
			result = list.get(0);
		}
		return result;
	}
	
	public void saveOrUpdate(DeviceInfo di){
		DeviceInfo getDi = getDIByImei(di.getImei());
		if(getDi==null){
			DaoFactory.getDiDao().save(di);
		}
	}