Hibernate的Session工厂

悠悠 2022-09-28 15:20 22阅读 0赞

package courses.hibernate.dao; import org.hibernate.HibernateException; import org.hibernate.Session; import org.hibernate.cfg.Configuration; /\*\* \* Configures and provides access to Hibernate sessions, tied to the \* current thread of execution. Follows the Thread Local Session \* pattern, see \{@link http://hibernate.org/42.html \}. \*/ public class HibernateSessionFactory \{ /\*\* \* Location of hibernate.cfg.xml file. \* Location should be on the classpath as Hibernate uses \* \#resourceAsStream style lookup for its configuration file. \* The default classpath location of the hibernate config file is \* in the default package. Use \#setConfigFile() to update \* the location of the configuration file for the current session. \*/ private static String CONFIG\_FILE\_LOCATION = "/hibernate.cfg.xml"; private static final ThreadLocal<Session> threadLocal = new ThreadLocal<Session>(); private static Configuration configuration = new Configuration(); private static org.hibernate.SessionFactory sessionFactory; private static String configFile = CONFIG\_FILE\_LOCATION; static \{ try \{ configuration.configure(configFile); sessionFactory = configuration.buildSessionFactory(); \} catch (Exception e) \{ System.err.println("%%%% Error Creating SessionFactory %%%%"); e.printStackTrace(); \} \} private HibernateSessionFactory()\{ \} /\*\* \* Returns the ThreadLocal Session instance. Lazy initialize \* the <code>SessionFactory</code> if needed. \* \* @return Session \* @throws HibernateException \*/ public static Session getSession() throws HibernateException \{ Session session = (Session) threadLocal.get(); if(session == null || !session.isOpen()) \{ if(sessionFactory == null) \{ rebuildSessionFactory(); \} session = (sessionFactory != null) ? sessionFactory.openSession() : null; threadLocal.set(session); \} return session; \} /\*\* \* Rebuild hibernate session factory \* \*/ public static void rebuildSessionFactory() \{ try \{ configuration.configure(configFile); sessionFactory = configuration.buildSessionFactory(); \} catch (Exception e) \{ System.err.println("%%%% Error Creating SessionFactory %%%%"); e.printStackTrace(); \} \} /\*\* \* Close the single hibernate session instance. \* \* @throws HibernateException \*/ public static void closeSession() throws HibernateException \{ Session session = (Session) threadLocal.get(); threadLocal.set(null); if(session != null) \{ session.close(); \} \} /\*\* \* return session factory \* \*/ public static org.hibernate.SessionFactory getSessionFactory() \{ return sessionFactory; \} /\*\* \* return session factory \* \* session factory will be rebuilded in the next call \*/ public static void setConfigFile(String configFile) \{ HibernateSessionFactory.configFile = configFile; sessionFactory = null; \} /\*\* \* return hibernate configuration \* \*/ public static Configuration getConfiguration() \{ return configuration; \} \}