如何正确启动SessionFactory？

Question

I will need to be connected to my database in almost every page of my website.

My first page is a Login so I intent to start the SessionFactory and keep it open for later use in other pages.

My question is: How can I declare the variable global so I can use it everywhere in my other classes?

 public SessionFactory StartDatabaseConnection() {
    SessionFactory factory;

    try {
         factory = new Configuration().configure().buildSessionFactory();
    } catch (Throwable ex) {
        System.err.println("Failed to create sessionFactory object." + ex);
        throw new ExceptionInInitializerError(ex);
    }
    return factory;
}

How do I use it here now?? factory doesn't exist in context

 private Integer addGeneralSetup(GeneralSetup generalSetup) {
    Session session = factory.openSession();
    Transaction tx = null;
    Integer generalSetupID = null;
    try{
        tx = session.beginTransaction();
        generalSetupID = (Integer) session.save(generalSetup);
        tx.commit();
    }catch (HibernateException e) {
        if (tx!=null) tx.rollback();
        e.printStackTrace();
    }finally {
        session.close();
    }
    return generalSetupID;
}

Answer 1

The best practice in my opinion is to use singleton spring bean and inject the dependency whenever required.

Spring provides 2 ways to achieve this: 1. Spring has inbuilt templates ready to be used For example:

  <bean id="sessionFactory" class="org.springframework.orm.hibernate3.LocalSessionFactoryBean"> 

2. You can declare your own bean with default scope and auto-wire it. Example:

 <bean id="customBean" class="com.learn.custom.CustomBean" />