在spring当中启用hibernate

系统管理员 2022-05-15 14:46 156阅读 0赞

有两种方式：

1. 在springContext.xml当中配置sessionFactory，然后就可以将这个SessionFactory注入到其它要使用hibernate的DAO当中去。

<bean id="sessionFactory"
    		class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">
    		<property name="configLocation">
    			<value>classpath:hibernate.cfg.xml</value>
    		</property>
    	</bean>
    	
    	<bean id="test" class="TestDAO">
    		<property name="sessionFactory">
    			<ref local="sessionFactory"/>
    		</property>
    	</bean>

这样，在TestDAO这个类当中就可以直接用SessionFactory来操作数据库了。

2. 不在xml文件当中进行配置，生成单独的一个类来通过hibernate.cfg.xml文件的位置来取得sessionFactory。这种方式其实就是上一种方式自己来实现。

下面是MyEclipse自动生成的一个sessionFactory的管理类，用户也可以自行实现。

package com.unews.hibernate.data;
    
    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;
    	}
    
    }