Spring中的Hibernate事务管理器配置 [英] Hibernate transaction manager configurations in Spring

问题描述

在我的项目中，我使用Hibernate和编程事务划分。
每次在我的Service方法中，我都写了类似的东西。

  Session session = HibernateUtil.getSessionFactory（）。的openSession（）; 
 session.beginTransaction（）; 
 ..在这里执行操作
 session.getTransaction（）。commit（）; 
  

现在我要用声明式事务管理重构我的代码。现在我得到了......

 < context：component-scan base-package =package。*/> 
 
< bean id =mySessionFactoryclass =org.springframework.orm.hibernate3.LocalSessionFactoryBean> 
< property name =configLocationvalue =classpath：hibernate.cfg.xml>< / property> 
< property name =configurationClass> 
< value> org.hibernate.cfg.AnnotationConfiguration< / value> 
< / property> 
< / bean> 
 
< tx：annotation-driven transaction-manager =txManager/> 
 
 
< bean id =txManagerclass =org.springframework.orm.hibernate3.HibernateTransactionManager> 
< property name =sessionFactory> 
< ref local =mySessionFactory/> 
< / property> 
< / bean> 
  

服务等级：

  @Service 
 public class TransactionalService {
 
 @Autowired 
 Private SessionFactory factory; 
 
 @Transactional 
 public User performSimpleOperation（）{
 return（User）factory.getCurrentSession（）。load（User.class，1L）; 
} 
} 
  

&简单测试 -

  @Test 
 public void useDeclarativeDem（）{
 FileSystemXmlApplicationContext ctx = new FileSystemXmlApplicationContext（spring-config.xml）; 
 TransactionalService b =（TransactionalService）ctx.getBean（transactionalService）; 
 User op = b.performSimpleOperation（）; 
 op.getEmail（）; 
  

当我尝试在事务性方法以外获取用户电子邮件时，我得到了懒惰初始化异常，电子邮件是我的情况是一个简单的字符串。 Hibernate甚至不执行sql查询，直到我调用POJO上的任何getter。

<1>我在这里做错了什么？

<2>这种方法是否有效？

3）你可以推荐任何opensource项目，在spring / hibernate上使用基于注解的配置吗？
$ b

更新

由于某些原因，如果我将 getCurrentSession 替换为 openSession ，此代码可以正常工作。有人可以解释一下吗？

谢谢

解决方案

最后我意识到了什么是问题。在上面的代码中，我使用load来代替get。 Session.load实际上并没有打到数据库。这就是为什么我在@Transactional方法之外获得懒惰初始化异常的原因。如果我使用openSession而不是getCurrentSession，会话将在范围spring容器之外打开。由于结果会话并不紧密，它允许我读取@Transactional方法以外的对象属性。

In my project I use Hibernate with programmatic transaction demarcation. Every time in my Service methods i write something similar to this.

Session session = HibernateUtil.getSessionFactory().openSession();
session.beginTransaction();
.. perform operation here
session.getTransaction().commit();

Now i'm going to refactor my code with declarative transaction management. What i got now ...

  <context:component-scan base-package="package.*"/>

  <bean id="mySessionFactory" class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">
    <property name="configLocation" value="classpath:hibernate.cfg.xml"></property>
    <property name="configurationClass">
        <value>org.hibernate.cfg.AnnotationConfiguration</value>
    </property>
  </bean>

  <tx:annotation-driven transaction-manager="txManager"/>


  <bean id="txManager"  class="org.springframework.orm.hibernate3.HibernateTransactionManager">
    <property name="sessionFactory">
         <ref local="mySessionFactory"/>
    </property>
  </bean>

Service class:

@Service
public class TransactionalService {

    @Autowired
    private SessionFactory factory;

    @Transactional
    public User performSimpleOperation() {
        return (User)factory.getCurrentSession().load(User.class, 1L);
    }
}

And simple test -

@Test
public void useDeclarativeDem() {
    FileSystemXmlApplicationContext ctx = new FileSystemXmlApplicationContext("spring-config.xml");
    TransactionalService b = (TransactionalService)ctx.getBean("transactionalService");
     User op = b.performSimpleOperation();
     op.getEmail();

When i try to get user email outside of Transactional method, i got Lazy initialization exception, email is my case is a simple string. Hibernate does not even perform sql query, until i call any getters on my POJO.

1) what i am doing wrong here ?

2) Is this approach valid ?

3) Can you suggest any opensources project wich work on spring/hibernate with annotation based configuration ?

Update

For some reason if i replace getCurrentSession with openSession this code works fine. Can someone explain it please ?

Thank you

解决方案

Ok, finally i realized what was the problem. In code above i used load instead of get. Session.load did not actually hit the databased. That's the reason why i get lazy-initialization exception outside of @Transactional method

If i use openSession instead of getCurrentSession, session is opened outside of scope spring container. As result session was not close and it allow me to read object properties outside of @Transactional method

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