Hibernate自动生成的DAO的修改方法

转载 Hibernate自动生成的DAO的修改方法

使用MyEclipse中用hibernate反向工程生成的DAO会发生对象无法存储到数据库的现象，原因是没有运用事务。DAO里注释提示如下：

/** * A data access object (DAO) providing persistence and search support for User * entities. Transaction control of the save(), update() and delete() operations * can directly support Spring container-managed transactions or they can be * augmented to handle user-managed Spring transactions. Each of these methods * provides additional information for how to configure it for the desired type * of transaction control. *  * @see org.hibernate.entity.User * @author MyEclipse Persistence Tools */

解决方法一、使用Spring的事务管理

方法二、修改DAO，添加事务处理

当然可以在调用dao对象的代码前后加事务控制，但这样破坏了dao对数据库操作的封装，让业务层中掺杂了持久层代码。所以进行以下修改：

import org.hibernate.Session;import org.hibernate.Transaction;public void save(Resource transientInstance) {        log.debug("saving Resource instance");        try {        Session session = getSession();         Transaction tr = session.beginTransaction(); //开始事务          session.save(transientInstance);        tr.commit();   //提交事务         session.flush();    //清空缓存            log.debug("save successful");        } catch (RuntimeException re) {            log.error("save failed", re);            throw re;        }    }public void delete(Resource persistentInstance) {        log.debug("deleting Resource instance");        try {        Session session = getSession();    Transaction tr = session.beginTransaction();                    session.delete(persistentInstance);            tr.commit();            session.flush();            log.debug("delete successful");        } catch (RuntimeException re) {            log.error("delete failed", re);            throw re;        }    }