hibernate查询返回DTO对象，DTO封装了多个pojo对象的属性

????? DTO-数据传输对象；pojo-最纯粹的java对象与数据库中的表一一对应。

????? 简单讲：DTO起到业务数据的传递作用，pojo则与持久层数据库打交道。

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????? 有时候我们需要查询返回DTO对象，因为DTO封装我们操作此对象的业务方法；而这些业务方法从分层的思想上看不能封装到pojo中，因为这违背了hibernate编程规范，pojo（public AccountDTO getAccountByUsernameAndPassword(AccountDTO accountDTO) {String sql = "SELECT" + " SIGNON.USERNAME," + " ACCOUNT.EMAIL," + " ACCOUNT.FIRSTNAME," + " ACCOUNT.LASTNAME," + " ACCOUNT.STATUS," + " ACCOUNT.ADDR1," + " ACCOUNT.ADDR2," + " ACCOUNT.CITY," + " ACCOUNT.STATE," + " ACCOUNT.ZIP," + " ACCOUNT.COUNTRY," + " ACCOUNT.PHONE," + " PROFILE.LANGPREF," + " PROFILE.FAVCATEGORY," + " PROFILE.MYLISTOPT," + " PROFILE.BANNEROPT," + " BANNERDATA.BANNERNAME" + " FROM ACCOUNT, PROFILE, SIGNON, BANNERDATA" + " WHERE ACCOUNT.USERID = ?" + " AND SIGNON.PASSWORD = ?" + " AND SIGNON.USERNAME = ACCOUNT.USERID" + " AND PROFILE.USERID = ACCOUNT.USERID" + " AND PROFILE.FAVCATEGORY = BANNERDATA.FAVCATEGORY";//Query query = this.getSession().createQuery(hql);//此方法有transaction的异常，因为我这里不是手动管理hibernate的事物，hibernate事物交给spring管理，此问题没能解决//Query query = this.getSessionFactory().getCurrentSession().createSQLQuery(sql).setResultTransformer(Transformers.aliasToBean(aDTO.class));Query query = this.getSession().createSQLQuery(sql).setResultTransformer(Transformers.aliasToBean(AccountDTO.class));query.setString(0, accountDTO.getUsername());query.setString(1, accountDTO.getPassword());return (AccountDTO) query.uniqueResult();}

?这里的重点方法：

Query query = this.getSession().createSQLQuery(sql).setResultTransformer(Transformers.aliasToBean(AccountDTO.class));

?原生sql的查询，返回结果设置到DTO，hibernate给我们做了处理，类似与jdbc的查询这里可能用到了反射，所以要求DTO中的属性要与表字段名称相同，并且为全都小写。（我试图在sql中使用别名，而且DTO中属性使用了驼峰命名，但结果出错。网上有文章说：只需别名和属性名称一致即可；但我测试未成功。有经验的朋友请指教！）

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搞完！