OOP风格的Hibernate延迟加载

Question

So, lets imagine that I have two objects: Course and Exercise . Course Contains list of Exercises.

Lazy loading is enabled, and via Repository I get a Course that I'm interested in:

couserRepo.query(new ByNameSpec("courseName")). 

Now I want to acces Course exercises, but when I call course.getExerccises() I get a msg, that session is closed already. So, I have to make another query to repo, that is absolutely not convinient.

What to do with this?

Answer 1

Remember that opening session per operation is antipattern. See http://docs.jboss.org/hibernate/orm/5.1/userguide/html_single/Hibernate_User_Guide.html#session-per-operation for more information.

The scope of a Hibernate org.hibernate.Session is flexible but you should never design your application to use a new Hibernate org.hibernate.Session for every database operation.

I think you should consider Session-per-request pattern.