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  • Hibernate原生SQL查询数据转换为HQL查询数据方法

    HQL形式:(构造方法不支持timestamp类型

    public List<Device> queryByMatherBoardId(String matherBoardId) {
            String hql = "select new Device(d.id,d.diskSize,d.diskSerial) from Device as d where d.matherBoard=:matherBoard";
            return this.getSession().createQuery(hql)
                    .setParameter("matherBoard", matherBoardId).list();
        }

      使用这种方式,Device构造方法不支持参数为time类型,会报无法匹配合适的构造方法错误。

    SQL形式:

    public List<Device> queryByMatherBoardId(String matherBoardId) {
        String sql = "select d.id,d.diskSize,d.diskSerial,d.registerTime from cems_device as d where d.matherBoardId=:matherBoardId order by registerTime asc";
        List<Device> list = getSession().createSQLQuery(hql)
                .setParameter("matherBoardId",matherBoardId)
                .list();
        return list;
    }

      使用这种方式呢,虽然不会报错,可以正常查询数据,但是获取的数据却是数组对象,达不到我们需要的实体对象的要求。

      查询的数据:select d.id,d.diskSize,d.diskSerial,d.registerTime from cems_device as d where d.matherBoardId='D8924D56-414C-ABCC-935A-A9D506926B31' ORDER BY registerTime ASC

      想要得到的数据:像下面这样实体类对象

      需要像下面这段代码一样转换下:

    public List<Device> queryByMatherBoardId(String matherBoardId) {
        Map<String,Object> map = new HashMap<String,Object>();
        String hql = "select d.id,d.diskSize,d.diskSerial,d.registerTime from cems_device as d where d.matherBoardId=:matherBoardId order by registerTime asc";
        map.put("matherBoardId",matherBoardId);
        Query q = getSession().createSQLQuery(hql)
                .addScalar("id", StandardBasicTypes.STRING)
                .addScalar("diskSize", StandardBasicTypes.INTEGER)
                .addScalar("diskSerial", StandardBasicTypes.STRING)
                .addScalar("registerTime", StandardBasicTypes.TIMESTAMP)
                .setResultTransformer(Transformers.aliasToBean(Device.class));
        q = assignValues(q, map);
        List<Device> list=(List<Device>)q.list();
        return list;
    }
    /**
     * 按名称绑定
     * @param query
     * @param values
     * @return
     */
    public Query assignValues(Query query, Map<String, ?> values) {
        if (values != null) {
            Set<String> keySet = values.keySet();
            for (String string : keySet) {
                Object obj = values.get(string);
                if (obj instanceof Collection<?>) {
                    query.setParameterList(string, (Collection<?>) obj);
                } else if (obj instanceof Object[]) {
                    query.setParameterList(string, (Object[]) obj);
                } else {
                    query.setParameter(string, obj);
                }
            }
        }
        return query;
    }

      这样就可以把之前对象数组数组转换为实体类对象数据。(主要是可以记住这个转换方法

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  • 原文地址:https://www.cnblogs.com/goloving/p/7649248.html
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