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我正在使用带有数据源连接的 Hibernate 5.0.2.Final(在 Tomcat 8.0.15 上),并开始问自己是否不仅需要关闭 Session,还需要关闭 SessionFactory?

现在它看起来像这样:

public static List<HibernateList> getHibernateList() {
        Session session = null;
        final String hql = "SELECT H FROM myhibernate.MyHibernate";
        try {
            SessionFactory factory = HibernateUtil.getSessionFactory();
            session = factory.openSession();
            session.beginTransaction();

            Query query = session.createQuery(hql);

            return query.list();
        } catch (HibernateException hibex) {
            Logger.getLogger(Hibernatepicker.class.getName()).log(Level.INFO, null, hql);
            Logger.getLogger(Hibernatepicker.class.getName()).log(Level.SEVERE, null, hibex);
        } finally {
            try {
                if (session != null) {
                    session.close();
                }
            } catch (HibernateException hibex) {
            }//Nothing I could do...
        }
        return null;
    }

hibernate.cfg.xml 中的一些细节

<property name="hibernate.connection.datasource">java:comp/env/jdbc/sqlserv</property>        
<property name="current_session_context_class">thread</property> 
<property name="cache.provider_class">org.hibernate.cache.NoCacheProvider</property> 
<property name="hbm2ddl.auto">auto</property> 
<property name="show_sql">false</property>       
<property name="hibernate.generate_statistics">true</property>  

还有 HibernateUtil:

public class HibernateUtil {
private static final SessionFactory sessionFactory;

static {
    try {
        Configuration cfg = new Configuration();
        sessionFactory = cfg.configure("hibernate.cfg.xml").buildSessionFactory();
    } catch (Throwable ex) {
        Logger.getLogger(HibernateUtil.class.getName()).log(Level.SEVERE, null, ex);
        throw new ExceptionInInitializerError(ex);
    }
}

public static SessionFactory getSessionFactory() {
    return sessionFactory;
}
}

我不确定是否有必要在 finally 块中调用此方法,而不是仅关闭会话:

public static void disconnect(Session session, SessionFactory factory) {
        try {
            if (session != null) {
                session.close();
            } else {
                Logger.getLogger(HibernateUtil.class.getName()).log(Level.INFO, null, "Session is Null");
        }

    } catch (HibernateException | NullPointerException hibex) {
        Logger.getLogger(HibernateUtil.class.getName()).log(Level.INFO, null, "Couldn't close session, but there's nothing we can do...");
        Logger.getLogger(HibernateUtil.class.getName()).log(Level.SEVERE, null, hibex);
    }
    try {
        if (factory != null) {
            factory.close();
        } else {
            Logger.getLogger(HibernateUtil.class.getName()).log(Level.INFO, null, "Factory is Null");
        }

    } catch (HibernateException | NullPointerException hibex) {
        Logger.getLogger(HibernateUtil.class.getName()).log(Level.INFO, null, "Couldn't close session, but there's nothing we can do...");
        Logger.getLogger(HibernateUtil.class.getName()).log(Level.SEVERE, null, hibex);
    }
}
4

1 回答 1

2

您不应该在每次查询时都关闭您的。SessionFactory每个应用程序只SessionFactory应初始化一次。

休眠文档

这里的主要合约是创建 Session 实例。通常,应用程序有一个 SessionFactory 实例,服务于客户端请求的线程从该工厂获取 Session 实例。SessionFactory 的内部状态是不可变的。一旦它被创建,这个内部状态就会被设置。此内部状态包括有关对象/关系映射的所有元数据。

实现者必须是线程安全的。

于 2015-10-20T13:51:24.873 回答