对象的动态延迟加载不起作用 [英] dynamically lazy loading of objects does not work

问题描述

我在我的项目中使用spring + hibernate;我有两个类提醒和客户端
在课堂提醒中，我添加了多对一的关系客户端，它是默认情况下急切加载。我想要这个对象图在我的项目中的大多数情况下，所以我已经设置提醒类中的客户提取类型

 类提醒{
 @ManyToOne 
客户端客户端; 
 
 $ / code> 

但是对于一个或两个场景我想保留这个对象客户端的初始化懒惰;



因此我在提取提示的方法中添加了如下所示：



 标准c = session.createCriteria（）; 
 c.setFetchMode（client，FetchMode.SELECT）; 
 hibernateTemplate.findByCriteria（criteria）; 
  

它不工作;它仍然加载提示客户对象

而反向（从懒惰到渴望）工作正常

解决方案

从api文档：

public static final FetchMode SELECT

 使用单独的选择快速获取。等同于fetch =select
  

AFAIK，如果映射是标记为懒惰，您可以使用标准或HQL查询热切地获取，但是不能做到相反：如果映射被标记为渴望，那么它总是会被热切地获取。

I am using spring + hibernate in my project; I have two classes Reminder and Client in class reminder i have added a relationship of many to one for client and it is by default eagerly loaded. I want this Object graph most of the scenarios in my project so i have set fetch type eager for client in reminder class

Class Reminder {
    @ManyToOne
    Client client;
}

but for one or two scenarios i want to keep initialization of this object client lazy;

so i have added in method for fetching reminders is like below

Criteria c = session.createCriteria();
c.setFetchMode("client", FetchMode.SELECT); 
hibernateTemplate.findByCriteria(criteria);

it is not working; it still loads client objects with reminder

while reverse (from lazy to eager) is working fine

解决方案

From the api doc:

public static final FetchMode SELECT

Fetch eagerly, using a separate select. Equivalent to fetch="select"

AFAIK, if a mapping is marked as lazy, you may fetch eagerly using a criteria or HQL query, but you can't do the reverse : if a mapping is marked as eager, then it'll always be fetched eagerly.

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