Java Hibernate：两个不同实体的投影（和）差异

我已经编写了一个sql代码来获取基于给定日期的某个项目的期末库存值

SELECT (SELECT Sum(qtyreceived) 
    FROM   purchaseinvoicedetails pid, 
           purchaseinvoice pi 
    WHERE  itemid_itemid = 1 
           AND pi.piid = pid.pidetails 
           AND pi.pidate < Curdate()) - (SELECT Sum(qtysent) 
                                         FROM   salesinvoicedetails sid, 
                                                salesinvoice si 
                                         WHERE  itemid_itemid = 1 
                                                AND si.siid = sid.siid_siid 
                                                AND si.sidate < Curdate()) 
   AS 
   closingstock 

它返回一个项目的期末存货价值

我希望使用hibernate标准实现同样的目标。 我搞不懂逻辑

提前谢谢