Question

其实我正在寻找在hibernate 4.2.x中使用session和DAO的最佳实践

第一种方法：

public class AccountDAOImpl implements AccountDAO {

    Session session=HibernateSessionFactoryUtil.getSession();
    Transaction transaction =null;
    @Override
    public void saveAccnt(Account account) {
        // TODO Auto-generated method stub
        try
        {
            transaction=session.beginTransaction();
            session.save(account);

            transaction.commit();

        }
        catch(RuntimeException re)
        {
            if(transaction!=null)
                transaction.rollback();
            throw re;
        }
        finally
        {
            session.close();
        }

    }
}

或我们采取第二种方法：

public class AccountDAOImpl implements AccountDAO {

    Session session=HibernateSessionFactoryUtil.getSession();
    Transaction transaction =null;
    @Override
    public void saveAccnt(Account account) {
        // TODO Auto-generated method stub
        try
        {
            transaction=session.beginTransaction();
            session.save(account);

            transaction.commit();

        }
        catch(RuntimeException re)
        {
            if(transaction!=null)
                transaction.rollback();
            throw re;
        }


    }
}

每次需要执行DAO的关闭会话中的实际差异需要在工作完成时关闭会话。

已更新：

public class HibernateSessionFactoryUtil {

private static SessionFactory sessionFactory=null;
public static Session getSession() {

    if(sessionFactory==null)
    {
        createSessionFactory();
    }


    return sessionFactory.openSession();
}


public static SessionFactory getSessionFactory() {
    if(sessionFactory==null)
    {
        createSessionFactory();
    }
    return sessionFactory;
}


private static void createSessionFactory() {
    Configuration configuration = new Configuration();
    configuration.configure("/hibernate.cfg.xml");

    ServiceRegistry serviceRegistry = new ServiceRegistryBuilder().applySettings(configuration.getProperties()).buildServiceRegistry();
     sessionFactory = configuration.buildSessionFactory(serviceRegistry);
}

}

Answer 1

你不应该用你的方法关闭会话：你没有在那里打开它。

做第二种方法，或者这样做：

public class AccountDAOImpl implements AccountDAO {

    @Override
    public void saveAccnt(Account account) {
        Transaction transaction =null;
        Session session=HibernateSessionFactoryUtil.getSession();
        try
        {
            transaction=session.beginTransaction();
            session.save(account);

            transaction.commit();

        }
        catch(RuntimeException re)
        {
            if(transaction!=null)
                transaction.rollback();
            throw re;
        }
        finally
        {
            session.close();
        }

    }
}

什么是hibernate会话和DAO的最佳实践

1 个答案: