Criteria联合分组查询+bject转对象，java实现Object转实体类备忘录

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Criteria分组查询，拿到的结果集中只有id,recordDate,device_id三个值：

Criteria crit = deviceRecordDao.getSession().createCriteria(DeviceRecord.class);ProjectionList proList = Projections.projectionList();        crit.setFetchMode("device", FetchMode.JOIN);        crit.setFetchMode("deviceRecord", FetchMode.JOIN);        crit.createAlias("device", "device");        crit.createAlias("device.office", "office");        crit.add(dataScopeFilter(user, "office", "", true));        crit.add(Restrictions.eq(DeviceRecord.FIELD_DEL_FLAG, DeviceRecord.DEL_FLAG_NORMAL));        crit.add(Restrictions.eq("device.delFlag", DeviceRecord.DEL_FLAG_NORMAL));        crit.addOrder(Order.desc("recordDate"));        proList.add(Projections.id());        proList.add(Projections.max("recordDate"));         proList.add(Projections.groupProperty("device.id"));        crit.setProjection(proList);         List results = crit.list();

results返回的是一个Object类型，要把它转换成相应的实体类：

List<DeviceRecord> topicList2 = Lists.newArrayList();          for(int i=0;i<results.size();i++){            DeviceRecord dr = new DeviceRecord();            Object[] obj = (Object[]) results.get(i);            dr.setId(obj[0].toString());            topicList2.add(dr);        }        return topicList2;

完成

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