spring hibernate 事务管理 OpenSessionInViewFilter

spring 配置文件的问题。关键是细心。 HibernateDaoSupport的子类在保存实体时抛出InvalidDataAccessApiUsageException异常，异常堆栈如下： org.springframework.dao.InvalidDataAccessApiUsageException: Write operations are not allowed in read-only mode (FlushMode.NEVER/MANUAL): Turn your Session into FlushMode.COMMIT/AUTO or remove 'readOnly' marker from transaction definition. at org.springframework.orm.hibernate3.HibernateTemplate.checkWriteOperationAllowed(HibernateTemplate.java:1090) at org.springframework.orm.hibernate3.HibernateTemplate$12.doInHibernate(HibernateTemplate.java:629) at org.springframework.orm.hibernate3.HibernateTemplate.execute(HibernateTemplate.java:367) at org.springframework.orm.hibernate3.HibernateTemplate.save(HibernateTemplate.java:627) 在网上搜了一下，其中大多数文章又是提OpenSessionInViewFilter又是提OpenSessionInViewInterceptor的，大多云山雾罩、不知所云。 其实这个异常的提示还是很明确的：在只读模式下(FlushMode.NEVER/MANUAL)写操作不被允许：把你的Session改成FlushMode.COMMIT/AUTO或者清除事务定义中的readOnly标记。 首先看一下我Spring的配置文件，为了减少篇幅，仅将与事务有关的一部分贴在下面： Xml代码 <?xml version="1.0" encoding="UTF-8"?>   <!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN" "http://www.springframework.org/dtd/spring-beans.dtd">   <beans>        <!-- Transaction template for Managers, from:             http://blog.exis.com/colin/archives/2004/07/31/concise-transaction-definitions-spring-11/ -->       <bean id="txProxyTemplate" abstract="true"            class="org.springframework.transaction.interceptor.TransactionProxyFactoryBean">           <property name="transactionManager">               <!--org.springframework.orm.hibernate3.HibernateTransactionManager的Bean实例-->               <ref bean="gkgltransactionManager" />           </property>           <property name="transactionAttributes">               <props>                   <prop key="save*">PROPAGATION_REQUIRED</prop>                   <prop key="remove*">PROPAGATION_REQUIRED</prop>                   <prop key="do*">PROPAGATION_SUPPORTS</prop>                    <prop key="auto*">PROPAGATION_SUPPORTS</prop>                   <!--对于其它方法要求事务并且是只读的-->                   <prop key="*">PROPAGATION_SUPPORTS,readOnly</prop>               </props>           </property>       </bean>       <!-- Generic manager that can be used to do basic CRUD operations on any objects -->       <bean id="manager" parent="txProxyTemplate">           <property name="target">               <bean class="com.neuqsoft.base.service.impl.BaseManager">                   <property name="dao">                       <ref bean="gkgldao" />                   </property>               </bean>           </property>       </bean>   </beans>   <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN" "http://www.springframework.org/dtd/spring-beans.dtd"> <beans> <!-- Transaction template for Managers, from: http://blog.exis.com/colin/archives/2004/07/31/concise-transaction-definitions-spring-11/ --> <bean id="txProxyTemplate" abstract="true" class="org.springframework.transaction.interceptor.TransactionProxyFactoryBean"> <property name="transactionManager"> <!--org.springframework.orm.hibernate3.HibernateTransactionManager的Bean实例--> <ref bean="gkgltransactionManager" /> </property> <property name="transactionAttributes"> <props> <prop key="save*">PROPAGATION_REQUIRED</prop> <prop key="remove*">PROPAGATION_REQUIRED</prop> <prop key="do*">PROPAGATION_SUPPORTS</prop> <prop key="auto*">PROPAGATION_SUPPORTS</prop> <!--对于其它方法要求事务并且是只读的--> <prop key="*">PROPAGATION_SUPPORTS,readOnly</prop> </props> </property> </bean> <!-- Generic manager that can be used to do basic CRUD operations on any objects --> <bean id="manager" parent="txProxyTemplate"> <property name="target"> <bean class="com.neuqsoft.base.service.impl.BaseManager"> <property name="dao"> <ref bean="gkgldao" /> </property> </bean> </property> </bean> </beans> 对于清除readOnly标记是很简单的，只需把上述配置文件中txProxyTemplate Bean定义中的<prop key="*">PROPAGATION_SUPPORTS,readOnly</prop>中的readOnly及其前面的逗号去掉即可。 接下来我们讨论把Session改成FlushMode.COMMIT/AUTO，下面是HibernateTemplate中checkWriteOperationAllowed方法的源码： Java代码 protected void checkWriteOperationAllowed(Session session) throws InvalidDataAccessApiUsageException {            if (isCheckWriteOperations() && getFlushMode() != FLUSH_EAGER &&                     session.getFlushMode().lessThan(FlushMode.COMMIT)) {                throw new InvalidDataAccessApiUsageException(                        "Write operations are not allowed in read-only mode (FlushMode.NEVER/MANUAL): "+                        "Turn your Session into FlushMode.COMMIT/AUTO or remove 'readOnly' marker from transaction definition.");             }         }   protected void checkWriteOperationAllowed(Session session) throws InvalidDataAccessApiUsageException { if (isCheckWriteOperations() && getFlushMode() != FLUSH_EAGER && session.getFlushMode().lessThan(FlushMode.COMMIT)) { throw new InvalidDataAccessApiUsageException( "Write operations are not allowed in read-only mode (FlushMode.NEVER/MANUAL): "+ "Turn your Session into FlushMode.COMMIT/AUTO or remove 'readOnly' marker from transaction definition."); } } 通过阅读这段代码我们不难看出，在Java代码中调用HibernateTemplate的save或者saveOrUpdate等涉及到写操作的方法之前需要把Session的刷新模式设置为FlushMode.COMMIT或更高的级别，或者把HibernateTemplate的刷新模式设置为FLUSH_EAGER，由于我们的Dao继承自HibernateDaoSupport，所以设置Session刷新模式的语句如下：getSession().setFlushMode(FlushMode.COMMIT); 而设置HibernateTemplate刷新模式的语句如下： Java代码 HibernateTemplate tmp=getHibernateTemplate();       tmp.setFlushMode(HibernateTemplate.FLUSH_EAGER);     HibernateTemplate tmp=getHibernateTemplate(); tmp.setFlushMode(HibernateTemplate.FLUSH_EAGER); 只要在调用HibernateTemplate涉及到写操作的方法之前正确设置了HibernateTemplate或者Session的刷新模式，则上述异常不会再抛出

 

 

 

 

 

 

 

 

 

 

 

第二种说法：

 

 

org. springframework. dao.InvalidDataAccessApiUsageException:
Write operations are not allowed in read-only mode (FlushMode.NEVER/MANUAL): Turn your Session into FlushMode.COMMIT/AUTO or remove 'readOnly' marker from transaction definition.

实际上这个问题不是第一次出现了 只是一直没有时间来研究它。今天得闲随即打开了OpenSessionInViewFilter这个文件。 首先先看一下我的web.xml配置

Java代码

1. <!-- openSessionInView -->   
2.     <filter>   
3.         <filter-name>openSessionInView</filter-name>   
4.         <filter-class>   
5.             org.springframework.orm.hibernate3.support.OpenSessionInViewFilter   
6.         </filter-class>   
7.     </filter>   
8.     <filter-mapping>   
9.         <filter-name>openSessionInView</filter-name>   
10.         <url-pattern>/*</url-pattern>   
11.     </filter-mapping>   
12.        
13.     <!--==================== rewriteFilter ====================-->   
14.   
15.     <!--==================== Spring ApplicationContext ====================-->   
16.     <listener>   
17.         <listener-class>   
18.             org.springframework.web.context.ContextLoaderListener   
19.         </listener-class>   
20.     </listener>   
21.     <context-param>   
22.         <param-name>contextConfigLocation</param-name>   
23.         <param-value>   
24.             classpath*:com/redgateonline/showradio/resource/spring/applicationContext*.xml   
25.         </param-value>   
26.     </context-param>   
27.   
28.     <!-- ==================== Webwork =================== -->  

<!-- openSessionInView -->
	<filter>
		<filter-name>openSessionInView</filter-name>
		<filter-class>
			org.springframework.orm.hibernate3.support.OpenSessionInViewFilter
		</filter-class>
	</filter>
	<filter-mapping>
		<filter-name>openSessionInView</filter-name>
		<url-pattern>/*</url-pattern>
	</filter-mapping>
	
	<!--==================== rewriteFilter ====================-->

	<!--==================== Spring ApplicationContext ====================-->
	<listener>
		<listener-class>
			org.springframework.web.context.ContextLoaderListener
		</listener-class>
	</listener>
	<context-param>
		<param-name>contextConfigLocation</param-name>
		<param-value>
			classpath*:com/redgateonline/showradio/resource/spring/applicationContext*.xml
		</param-value>
	</context-param>

	<!-- ==================== Webwork =================== -->

之前一直怀疑是filter配置的顺序问题 ，有几次修改了配置文件后问题就解决了。
先来看看OpenSessionInViewFilter中的doFilterInternal()方法，这里只给出关键部分，

Java代码

1. //从servletContext中取sessionFactory   
2. SessionFactory sessionFactory = lookupSessionFactory(request);   
3.         boolean participate = false;   
4.   
5.         if (isSingleSession()) {   
6.             // single session mode   
7.             if (TransactionSynchronizationManager.hasResource(sessionFactory)) {   
8.                 // Do not modify the Session: just set the participate flag.   
9.                 participate = true;   
10.             }   
11.             else {   
12.                 logger.debug("Opening single Hibernate Session in OpenSessionInViewFilter");   
13.                    
14. Session session = getSession(sessionFactory); //通过sessionFactory获取session，这个session被绑定到当前线程中 在整个request期间使用   
15.                 TransactionSynchronizationManager.bindResource(sessionFactory, new SessionHolder(session));   
16.             }   
17.         }   
18.         else {   
19.             // deferred close mode   
20.             if (SessionFactoryUtils.isDeferredCloseActive(sessionFactory)) {   
21.                 // Do not modify deferred close: just set the participate flag.   
22.                 participate = true;   
23.             }   
24.             else {   
25.                 SessionFactoryUtils.initDeferredClose(sessionFactory);   
26.             }   
27.         }  

//从servletContext中取sessionFactory
SessionFactory sessionFactory = lookupSessionFactory(request);
		boolean participate = false;

		if (isSingleSession()) {
			// single session mode
			if (TransactionSynchronizationManager.hasResource(sessionFactory)) {
				// Do not modify the Session: just set the participate flag.
				participate = true;
			}
			else {
				logger.debug("Opening single Hibernate Session in OpenSessionInViewFilter");
				
Session session = getSession(sessionFactory); //通过sessionFactory获取session，这个session被绑定到当前线程中 在整个request期间使用
				TransactionSynchronizationManager.bindResource(sessionFactory, new SessionHolder(session));
			}
		}
		else {
			// deferred close mode
			if (SessionFactoryUtils.isDeferredCloseActive(sessionFactory)) {
				// Do not modify deferred close: just set the participate flag.
				participate = true;
			}
			else {
				SessionFactoryUtils.initDeferredClose(sessionFactory);
			}
		}

看看Session session = getSession(sessionFactory);中的getSession(sessionFactory)是怎么实现的

Java代码

1. protected Session getSession(SessionFactory sessionFactory) throws DataAccessResourceFailureException {   
2.         Session session = SessionFactoryUtils.getSession(sessionFactory, true);   
3.         FlushMode flushMode = getFlushMode();   
4.         if (flushMode != null) {   
5.             session.setFlushMode(flushMode);   
6.         }   
7.         return session;   
8.     }  

protected Session getSession(SessionFactory sessionFactory) throws DataAccessResourceFailureException {
		Session session = SessionFactoryUtils.getSession(sessionFactory, true);
		FlushMode flushMode = getFlushMode();
		if (flushMode != null) {
			session.setFlushMode(flushMode);
		}
		return session;
	}

OpenSessionInViewFilter有一个变量flushMode，可通过getter setter为其赋值，而其默认值为FlushMode.NEVER，这儿的NEVER值已经被deprecate了。
原来是这儿在捣鬼，只要写了子类覆盖setFlushMode(FlushMode.auto);就ok了