OpenSessionInView working but not providing its session for @Transactional

Question

I am trying to use Spring MVC 3 and Hibernate 4.1 to get declarative transaction management, providing an open session for the entire length of the request. I only have one "manager" layer for data access, which directly uses the session. This is annotated with @Transactional, and the session closes upon exiting this layer and I get a lazy load exception in the controller.

So I added the OpenSessionInViewFilter filter, and the logs state that this filter is correctly configured and they also show this filter opening a session. Unfortunately, my manager layer opens and closes its own session anyway, just as before, and I get the same lazy load exception in the controller.

Edit: noted that in my log, I get the filter session open, HibernateTransactionManager session open, HibernateTransactionManager session closed, lazy load exception, then filter session closed. So I know that there is an open session somewhere during the lazy load exception, but the object was loaded in a transaction associated with the other, closed session.

I thought that removing @Transactional from the manager class would remove session management from that layer and let the filter do its job, but then the sessionFactory().getCurrentSession() simply gets a closed session; it doesn't have access to the filter's provided open session.

How can I get access to the OpenSessionInViewFilter's clearly open session?

springapp-servlet.xml

<beans ..

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

<bean class="org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping"/>
<bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter"/>

<!-- Enables the Spring MVC @Controller programming model -->
<mvc:annotation-driven />

<bean id="userManager" class="springapp.service.SimpleUserManager">
    <property name="sessionFactory" ref="sessionFactory" />
</bean>

<bean id="viewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
    <property name="prefix" value="/WEB-INF/jsp/" />
    <property name="suffix" value=".jsp" />
</bean>

<import resource="hibernate-context.xml" />

</beans>

web.xml

<listener>
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>

<context-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>/WEB-INF/springapp-servlet.xml</param-value>
</context-param>

<filter>
    <filter-name>openSessionInView</filter-name>
    <filter-class>org.springframework.orm.hibernate4.support.OpenSessionInViewFilter</filter-class>
    <init-param>
        <param-name>sessionFactoryBeanName</param-name>
        <param-value>sessionFactory</param-value>
    </init-param>
</filter>

<filter-mapping>
    <filter-name>openSessionInView</filter-name>
    <url-pattern>/*</url-pattern>
</filter-mapping>

<servlet>
    <servlet-name>springapp</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
</servlet>

<servlet-mapping>
    <servlet-name>springapp</servlet-name>
    <url-pattern>/</url-pattern>
</servlet-mapping>

hibernate-context.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans ..
  ">

<context:property-placeholder location="/WEB-INF/hibernate.properties" />

<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close">
    <property name="driverClassName" value="${hibernate.connection.driver_class}" />
    <property name="url" value="${hibernate.connection.url}" />
    <property name="username" value="${hibernate.connection.username}" />
    <property name="password" value="${hibernate.connection.password}" />
</bean>

<bean id="transactionManager" class="org.springframework.orm.hibernate4.HibernateTransactionManager">
    <property name="sessionFactory" ref="sessionFactory"/>
</bean>

<tx:annotation-driven />

<bean id="transactionInterceptor" class="org.springframework.transaction.interceptor.TransactionInterceptor">
    <property name="transactionManager" ref="transactionManager" />
    <property name="transactionAttributeSource">
        <bean class="org.springframework.transaction.annotation.AnnotationTransactionAttributeSource" />
    </property>
</bean>

<bean id="managerTemplate" abstract="true" class="org.springframework.aop.framework.ProxyFactoryBean">
    <property name="interceptorNames">
        <list>
            <value>transactionInterceptor</value>
        </list>
    </property>
</bean>

<bean id="sessionFactory" class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
    <property name="packagesToScan" value="databeans" />
    <property name="dataSource" ref="dataSource" />
    <property name="hibernateProperties">
        <props>
            <prop key="hibernate.dialect">${hibernate.dialect}</prop>
        </props>
    </property>
</bean>

</beans>

manager.java

@Service("userManager")
@Transactional
public class SimpleUserManager implements UserManager {

@Autowired
private SessionFactory sessionFactory;

public void setSessionFactory(SessionFactory sessionFactory){
    this.sessionFactory = sessionFactory;
}
..

controller.java

@Controller
@RequestMapping("/users")
public class UserController {

@Autowired
private UserManager userManager;
..

and my exception, which occurs in the controller, on the first property read of an object loaded in the manager class and passed to that controller:

org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.hibernate.LazyInitializationException: could not initialize proxy - no Session org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:894) org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:778) javax.servlet.http.HttpServlet.service(HttpServlet.java:617) javax.servlet.http.HttpServlet.service(HttpServlet.java:717) org.springframework.orm.hibernate4.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:119) org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)

I've been researching this for hours.. all I can find is a mix of solutions using hibernate 3 and grainy explanations on hibernate 4 session/transaction theory without examples.

Any thoughts?

UPDATE: FIXED!

Found this:

Spring MVC OpenSessionInViewInterceptor Not Working

which unfortunately has not helped the OP there, but it helped me. Notably, this:

"it will be better to not import applicationContext.xml in dispatcher-servlet.xml, instead load it using a ContextLoaderListener"

which, applied to my configuration, is exactly everything I have posted above, but instead of

<import resource="hibernate-context.xml" />

in my springapp-servlet.xml, I modified my ContextLoaderListener to:

<context-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>/WEB-INF/springapp-servlet.xml, /WEB-INF/hibernate-context.xml</param-value>
</context-param>

and that was all it took for

sessionFactory.getCurrentSession()

to return to me the OSIV-created session. And, in fact, the second session that was being created is no longer, as I found these lovely little log lines:

2012-10-04 14:43:48,743 DEBUG http-8080-1 org.springframework.beans.factory.support.DefaultListableBeanFactory - Returning cached instance of singleton bean 'transactionManager'
2012-10-04 14:43:48,743 TRACE http-8080-1 org.springframework.transaction.support.TransactionSynchronizationManager - Retrieved value [org.springframework.orm.hibernate4.SessionHolder@4146c5c0] for key [org.hibernate.internal.SessionFactoryImpl@12542011] bound to thread [http-8080-1]
2012-10-04 14:43:48,743 DEBUG http-8080-1 org.springframework.orm.hibernate4.HibernateTransactionManager - Found thread-bound Session [SessionImpl(PersistenceContext[entityKeys=[],collectionKeys=[]];ActionQueue[insertions=[] updates=[] deletions=[] collectionCreations=[] collectionRemovals=[] collectionUpdates=[] unresolvedInsertDependencies=UnresolvedEntityInsertActions[]])] for Hibernate transaction
2012-10-04 14:43:48,743 DEBUG http-8080-1 org.springframework.orm.hibernate4.HibernateTransactionManager - Creating new transaction with name [springapp.service.SimpleUserManager.find]: PROPAGATION_REQUIRED,ISOLATION_DEFAULT; ''

which show that, outside of my @Transactional service layer, the OSIV-created session was alive and well, and a new transaction was simply started for it.

Hope this helps someone else. I don't even want to think about how many hours I spent working on it.