HibernateUtil-优快云博客

本文介绍了HibernateUtil工具类的实现细节，包括如何配置、获取和重建SessionFactory，以及如何通过线程本地变量管理Session实例。此外，还展示了如何关闭Session和SessionFactory，确保资源得到合理释放。

下面是HibernateUtil代码：

package com.lml.util;

import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
import org.hibernate.cfg.Configuration;
import org.hibernate.service.ServiceRegistry;

public class HibernateUtil {

private static String configFile = "/hibernate.cfg.xml";
private static final ThreadLocal<Session> threadLocal = new ThreadLocal<Session>();
private static Configuration configuration = new Configuration();
private static org.hibernate.SessionFactory sessionFactory;

static {
try {
configuration.configure(configFile);

ServiceRegistry serviceRegistry = new StandardServiceRegistryBuilder()
.applySettings( configuration.getProperties() )
.build();
sessionFactory= configuration.buildSessionFactory(serviceRegistry);

} catch (Exception e) {
e.printStackTrace();
}
}

private HibernateUtil() {
}

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;
}

public static void rebuildSessionFactory() {
try {
configuration.configure(configFile);
ServiceRegistry serviceRegistry = new StandardServiceRegistryBuilder()
.applySettings( configuration.getProperties() )
.build();
sessionFactory= configuration.buildSessionFactory(serviceRegistry);

} catch (Exception e) {
e.printStackTrace();
}
}

public static void closeSession() throws HibernateException {
Session session = (Session) threadLocal.get();
threadLocal.set(null);

if (session != null) {
session.close();
}
}

public static org.hibernate.SessionFactory getSessionFactory() {
return sessionFactory;
}

public static void setConfigFile(String configFile) {
HibernateUtil.configFile = configFile;
sessionFactory = null;
}

public static Configuration getConfiguration() {
return configuration;
}

public static void shutdown(){
getSessionFactory().close();
}

}