通过servlet中的Hibernate进行数据库连接

Question

What is the best place in servlet for Hibernate code that returns HibernateSessionFactory ?

I saw many examples: ones put db connection in service methods. Others - use smth like HibernateUtil (Singleton) that returns HibernateSessionFactory.

I don't know is it safe to use HibernateUtil in multithreaded Servlets ?

Answer 1

Usually, you should use an MVC framework in favor of Servlets directly, but that's not your question, and I'm going to assume you have a good reason to be implementing your own Servlets. On to the answer...

Per this - https://www.hibernate.org/hib_docs/v3/api/org/hibernate/SessionFactory.html :

Implementors must be threadsafe.

and

SessionFactorys are immutable. The behaviour of a SessionFactory is controlled by properties supplied at configuration time. These properties are defined on Environment .

So it's OK to share an instance of SessionFactory s.

In fact, from my experience, your HibernateUtil approach is the better approach, as SessionFactory creation can be very expensive.

Answer 2

在视图模式中使用Open Session （请参阅过滤器实现）。