为何OpenSessionInView不能同时保存和删除

代码:

<filter>         <filter-name>opensession</filter-name>         <filter-class>org.springframework.orm.hibernate3.support.OpenSessionInViewFilter</filter-class>     </filter>

写了个保存的代码测试了一下,报如下的错误:

代码:

org.springframework.dao.InvalidDataAccessApiUsageException: Write operations are not allowed in read-only mode (FlushMode.NEVER) - turn your Session into FlushMode.AUTO or remove 'readOnly' marker from transaction definition    at org.springframework.orm.hibernate3.HibernateTemplate.checkWriteOperationAllowed(HibernateTemplate.java:1076)    at org.springframework.orm.hibernate3.HibernateTemplate$12.doInHibernate(HibernateTemplate.java:616)    at org.springframework.orm.hibernate3.HibernateTemplate.execute(HibernateTemplate.java:366)    at org.springframework.orm.hibernate3.HibernateTemplate.save(HibernateTemplate.java:614)    at com.phopesoft.security.service.impl.UserServiceImpl.addUser(UserServiceImpl.java:40)    at com.phopesoft.security.web.UserAction.add(UserAction.java:52)    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)    at java.lang.reflect.Method.invoke(Method.java:585)    at com.opensymphony.xwork.DefaultActionInvocation.invokeAction(DefaultActionInvocation.java:365) ................

在javaeye中搜索了一下,发现了Readonly的帖子,将web.xml修改为如下:

代码:

<filter>         <filter-name>opensession</filter-name>         <filter-class>org.springframework.orm.hibernate3.support.OpenSessionInViewFilter</filter-class>         <init-param>             <param-name>singleSession</param-name>             <param-value>false</param-value>         </init-param>     </filter>

保存的代码顺利通过测试,但是删除的代码却不能通过了.出现如下的错误:

代码:

org.hibernate.HibernateException: Illegal attempt to associate a collection with two open sessions    at org.hibernate.collection.AbstractPersistentCollection.setCurrentSession(AbstractPersistentCollection.java:410)    at org.hibernate.event.def.OnUpdateVisitor.processCollection(OnUpdateVisitor.java:40)    at org.hibernate.event.def.AbstractVisitor.processValue(AbstractVisitor.java:101)    at org.hibernate.event.def.AbstractVisitor.processValue(AbstractVisitor.java:61)    at org.hibernate.event.def.AbstractVisitor.processEntityPropertyValues(AbstractVisitor.java:55)    at org.hibernate.event.def.AbstractVisitor.process(AbstractVisitor.java:123)    at org.hibernate.event.def.DefaultDeleteEventListener.onDelete(DefaultDeleteEventListener.java:72)    at org.hibernate.impl.SessionImpl.fireDelete(SessionImpl.java:790)    at org.hibernate.impl.SessionImpl.delete(SessionImpl.java:768)    at org.springframework.orm.hibernate3.HibernateTemplate$25.doInHibernate(HibernateTemplate.java:772)    at org.springframework.orm.hibernate3.HibernateTemplate.execute(HibernateTemplate.java:366)    at org.springframework.orm.hibernate3.HibernateTemplate.delete(HibernateTemplate.java:766)    at org.springframework.orm.hibernate3.HibernateTemplate.delete(HibernateTemplate.java:762)

 

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首先要说明一下Open Session in View的作用，就是允许在每次的整个request的过程中使用同一个hibernate session,可以在这个request任
何时期lazy loading数据。
如果是singleSession=false的话，就不会在每次的整个request的过程中使用同一个hibernate session,而是每个数据访问都会产生各自的seesion,等于没有Open Session in View.
OpenSessionInViewFilter默认是不会对session 进行flush的,并且flush mode 是 never

代码:

protected Session getSession(SessionFactory sessionFactory) throws DataAccessResourceFailureException {       Session session = SessionFactoryUtils.getSession(sessionFactory, true);       session.setFlushMode(FlushMode.NEVER);       return session;    }

看getSession的方式就知道,把flush mode 设为FlushMode.NEVER,这样就算是commit的时候也不会session flush,
如果想在完成request过程中更新数据的话, 那就需要先把flush model设为FlushMode.AUTO,再在更新完数据后flush.

 

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嗯,是事务的问题,感谢差沙也感谢cac的回复.

OpenSessionInView默认的FlushMode为

代码:

FlushMode.NEVER

可以采用在写保存更新删除代码的时候手动更改FlushMode

代码:

this.getHibernateTemplate().execute(new HibernateCallback() {             public Object doInHibernate(Session session) throws HibernateException {                 session.setFlushMode(FlushMode.AUTO);                 session.save(user);                 session.flush();                 return null;             }         });

但是这样做太繁琐了,第二种方式是采用spring的事务声明

代码:

<bean id="baseTransaction" class="org.springframework.transaction.interceptor.TransactionProxyFactoryBean"           abstract="true">         <property name="transactionManager" ref="transactionManager"/>         <property name="proxyTargetClass" value="true"/>         <property name="transactionAttributes">             <props>                 <prop key="get*">PROPAGATION_REQUIRED,readOnly</prop>                 <prop key="find*">PROPAGATION_REQUIRED,readOnly</prop>                 <prop key="load*">PROPAGATION_REQUIRED,readOnly</prop>                 <prop key="save*">PROPAGATION_REQUIRED</prop>                 <prop key="add*">PROPAGATION_REQUIRED</prop>                 <prop key="update*">PROPAGATION_REQUIRED</prop>                 <prop key="remove*">PROPAGATION_REQUIRED</prop>             </props>         </property>     </bean>

<o:p> </o:p>

代码:

<bean id="userService" parent="baseTransaction">         <property name="target">             <bean class="com.phopesoft.security.service.impl.UserServiceImpl"/>         </property>     </bean>

 

来源:http://spring.jactiongroup.net/viewtopic.php?p=5791

谢谢各位<v:shapetype id="_x0000_t75" coordsize="21600,21600" o:spt="75" o:preferrelative="t" path="m@4@5l@4@11@9@11@9@5xe" filled="f" stroked="f"><v:stroke joinstyle="miter"></v:stroke><v:formulas><v:f eqn="if lineDrawn pixelLineWidth 0"></v:f><v:f eqn="sum @0 1 0"></v:f><v:f eqn="sum 0 0 @1"></v:f><v:f eqn="prod @2 1 2"></v:f><v:f eqn="prod @3 21600 pixelWidth"></v:f><v:f eqn="prod @3 21600 pixelHeight"></v:f><v:f eqn="sum @0 0 1"></v:f><v:f eqn="prod @6 1 2"></v:f><v:f eqn="prod @7 21600 pixelWidth"></v:f><v:f eqn="sum @8 21600 0"></v:f><v:f eqn="prod @7 21600 pixelHeight"></v:f><v:f eqn="sum @10 21600 0"></v:f></v:formulas><v:path o:extrusionok="f" gradientshapeok="t" o:connecttype="rect"></v:path><o:lock v:ext="edit" aspectratio="t"></o:lock></v:shapetype><v:shape id="_x0000_i1025" style="WIDTH: 11.25pt; HEIGHT: 11.25pt" type="#_x0000_t75" alt="Smile"><v:imagedata src="file:///C:\DOCUME~1\Q\LOCALS~1\Temp\msohtml1\01\clip_image001.gif" o:href="http://spring.jactiongroup.net/images/smiles/icon_smile.gif"></v:imagedata></v:shape>同样在论坛里面搜索到遇到这个问题的朋友,回帖说去掉singleSession!

迷惑了<v:shapetype id="_x0000_t75" coordsize="21600,21600" o:spt="75" o:preferrelative="t" path="m@4@5l@4@11@9@11@9@5xe" filled="f" stroked="f"><v:stroke joinstyle="miter"></v:stroke><v:formulas><v:f eqn="if lineDrawn pixelLineWidth 0"></v:f><v:f eqn="sum @0 1 0"></v:f><v:f eqn="sum 0 0 @1"></v:f><v:f eqn="prod @2 1 2"></v:f><v:f eqn="prod @3 21600 pixelWidth"></v:f><v:f eqn="prod @3 21600 pixelHeight"></v:f><v:f eqn="sum @0 0 1"></v:f><v:f eqn="prod @6 1 2"></v:f><v:f eqn="prod @7 21600 pixelWidth"></v:f><v:f eqn="sum @8 21600 0"></v:f><v:f eqn="prod @7 21600 pixelHeight"></v:f><v:f eqn="sum @10 21600 0"></v:f></v:formulas><v:path o:extrusionok="f" gradientshapeok="t" o:connecttype="rect"></v:path><o:lock v:ext="edit" aspectratio="t"></o:lock></v:shapetype><v:shape id="_x0000_i1025" style="WIDTH: 11.25pt; HEIGHT: 11.25pt" type="#_x0000_t75" alt="Sad"><v:imagedata src="file:///C:\DOCUME~1\Q\LOCALS~1\Temp\msohtml1\01\clip_image001.gif" o:href="http://spring.jactiongroup.net/images/smiles/icon_sad.gif"></v:imagedata></v:shape>