学步园

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