Hibernate的getCurrentSession和openSession的区别

getHiberanteTemplate 、getCurrentSession和OpenSession

采用getCurrentSession()创建的Session会绑定到当前的线程中去、而采用OpenSession()则不会。

采用getCurrentSession()创建的Session在commit或rollback后会自动关闭，采用OpenSession()必须手动关闭。

采用getCurrentSession()需要在Hibernate.cfg.xml配置文件中加入如下配置：

如果是本地事物，及JDBC一个数据库：

<propety name=”Hibernate.current_session_context_class”>thread</propety>

如果是全局事物，及jta事物、多个数据库资源或事物资源：

<propety name=”Hibernate.current_session_context_class”>jta</propety>

使用spring的getHiberanteTemplate 就不需要考虑事务管理和session关闭的问题：

public List getEntityCriteria(final DetachedCriteria detachedCriteria) {
        return (List) getHibernateTemplate().executeFind(
                new HibernateCallback() {
                    public Object doInHibernate(Session session)
                            throws HibernateException {
                        Criteria criteria = detachedCriteria
                                .getExecutableCriteria(session);
                        return criteria.list();
                    }
                });
    }
    public List getEntityCriteriaByPage(final DetachedCriteria detachedCriteria,final Page page) {
        return (List) getHibernateTemplate().executeFind(
                new HibernateCallback() {
                    public Object doInHibernate(Session session)
                            throws HibernateException {
                        Criteria criteria = detachedCriteria
                                .getExecutableCriteria(session);

                        criteria.setFirstResult(page.getFirstItemPos());
                        criteria.setMaxResults(page.getPageSize());
                        return criteria.list();
                    }
                });
    }

DetachedCriteria detachedCriteria = DetachedCriteria.forClass(Department.class);

detachedCriteria.add(Restrictions.eq("eid", seacher.getEid()));//企业id为条件查询

detachedCriteria.add(Restrictions.in("dprtid", ids));//根据id数组查询部门

detachedCriteria.add(Restrictions.like("name", "%" + seacher.getName()+ "%"));//名称模糊查询

getEntityCriteriaByPage(detachedCriteria,pageinfo);

经过检查激活连接为0，被使用的连接总是为1（应为自己测试）

BasicDataSource newDataSource = (BasicDataSource) Global._ctx
        .getBean("datasource_"+hibernateEntityName);
        newDataSource.getNumActive();
        newDataSource.getInitialSize();
        newDataSource.getMaxActive();
        newDataSource.getMaxIdle();
        newDataSource.getNumIdle();