spring-4.2.2 + hibernate-4.3.8通過HibernateSessionFactory建立sessionFactory

代碼如下：

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配置檔案路徑
	private static String CONFIG_FILE_LOCATON = "/hibernate.cfg.xml";
	// 建立ThreadLocal
	private static final ThreadLocal<Session> sessionThreadLocal = new ThreadLocal<Session>();
	// 建立Configuration對象
	private static Configuration configuration = new Configuration();
	// 定義Session對象

	private static SessionFactory sessionFactory;
	// 定義configFile屬性并指派

	private static String ConfigFile = CONFIG_FILE_LOCATON;
	static {
		try {
			// 讀取配置檔案Hibernate.cfg.xml
			// configuration.configure()預設在classpath下尋找Hibernate檔案
			/*
			 * 所有基于Hibernate的配置或者服務都必須統一向這個ServiceRegistry注冊後才能生效。 是以不難看出
			 * Hibernate4的配置入口不再是Configuration對象，而是ServiceRegistry對象，
			 * Configuration對象将通過ServiceRegistry對象擷取配置資訊。
			 * 使用了Builder模式建立一個ServiceRegistry對象，可以看到源碼org.hibernate.service.
			 * ServiceRegistryBuilder這個類。
			 */
			configuration.configure();
			// 生成一個注冊機對象
			ServiceRegistry serviceRegistry = new StandardServiceRegistryBuilder()
					.applySettings(configuration.getProperties()).build();
			// 使用注冊機對象ServiceRegistry建立SessionFactory
			sessionFactory = configuration.buildSessionFactory(serviceRegistry);
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

	// 建立無參的HibernateSessionFactory構造方法
	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();
			}

		}
	}

	// 獲得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;

	}

	// 必須手動關閉
	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屬性的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;
	}

}