spring-4.2.2 + hibernate-4.3.8通过HibernateSessionFactory创建sessionFactory

淩亂°似流年 2023-10-18 22:58 24阅读 0赞

### 代码如下： ###

package demo.ssh.entity;
    
    import org.hibernate.Session;
    import org.hibernate.SessionFactory;
    import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
    import org.hibernate.cfg.Configuration;
    import org.hibernate.service.ServiceRegistry;
    
    public class HibernateSessionFactory {
    
    	// 指定Hibernate配置文件路径
    	private static String CONFIG_FILE_LOCATON = "/hibernate.cfg.xml";
    	// 创建ThreadLocal
    	private static final ThreadLocal<Session> sessionThreadLocal = new ThreadLocal<Session>();
    	// 创建Configuration对象
    	private static Configuration configuration = new Configuration();
    	// 定义Session对象
    
    	private static SessionFactory sessionFactory;
    	// 定义configFile属性并赋值
    
    	private static String ConfigFile = CONFIG_FILE_LOCATON;
    	static {
    		try {
    			// 读取配置文件Hibernate.cfg.xml
    			// configuration.configure()默认在classpath下寻找Hibernate文件
    			/*
    			 * 所有基于Hibernate的配置或者服务都必须统一向这个ServiceRegistry注册后才能生效。 所以不难看出
    			 * Hibernate4的配置入口不再是Configuration对象，而是ServiceRegistry对象，
    			 * Configuration对象将通过ServiceRegistry对象获取配置信息。
    			 * 使用了Builder模式创建一个ServiceRegistry对象，可以看到源码org.hibernate.service.
    			 * ServiceRegistryBuilder这个类。
    			 */
    			configuration.configure();
    			// 生成一个注册机对象
    			ServiceRegistry serviceRegistry = new StandardServiceRegistryBuilder()
    					.applySettings(configuration.getProperties()).build();
    			// 使用注册机对象ServiceRegistry创建SessionFactory
    			sessionFactory = configuration.buildSessionFactory(serviceRegistry);
    		} catch (Exception e) {
    			e.printStackTrace();
    		}
    	}
    
    	// 创建无参的HibernateSessionFactory构造方法
    	public static SessionFactory getSessionFactory() {
    		return sessionFactory;
    	}
    
    	// 重建SessionFactory
    	public static void rebuildSessionFactory() {
    		synchronized (sessionFactory) {
    			try {
    				configuration.configure(ConfigFile);
    				ServiceRegistry serviceRegistry = new StandardServiceRegistryBuilder()
    						.applySettings(configuration.getProperties()).build();
    				sessionFactory = configuration.buildSessionFactory(serviceRegistry);
    			} catch (Exception e) {
    				e.printStackTrace();
    			}
    
    		}
    	}
    
    	// 获得session
    	public static Session getSession() {
    		Session session = (Session) sessionThreadLocal.get();
    		try {
    			if (session == null || !session.isOpen()) {
    				if (sessionFactory == null) {
    					rebuildSessionFactory();
    				}
    			}
    
    			session = (sessionFactory != null) ? sessionFactory.openSession() : null;
    			sessionThreadLocal.set(session);
    		} catch (Exception e) {
    			e.printStackTrace();
    
    		}
    		return session;
    
    	}
    
    	// 必须手动关闭
    	public static void closeSession() {
    		Session session = (Session) sessionThreadLocal.get();
    		sessionThreadLocal.set(null);
    		try {
    			if (session != null && session.isOpen()) {
    				session.close();
    			}
    		} catch (Exception e) {
    			e.printStackTrace();
    		}
    	}
    
    	// configFile属性的set方法
    	public static void setConfigFile(String configFile) {
    		HibernateSessionFactory.ConfigFile = configFile;
    		sessionFactory = null;
    	}
    
    	// configuration的get方法
    	public static Configuration getConfiguration() {
    		return configuration;
    	}
    
    }