I need to use query that fetches objects from multiple entity groups
(which means I can't use transactions). Here's the method:
@Override
public Collection<Item> findInactiveItems(Date endDate) {
inactiveItems =
em.createNamedQuery("findInactiveItems").setParameter("endDate",
endDate).getResultList();
if(null == inactiveItems) inactiveItems = new ArrayList<Item>();
inactiveItems.size();
return inactiveItems;
}
However, calling getResultList() causes the following error:
Caused by: org.datanucleus.exceptions.NucleusUserException: Object
Manager has been closed
at
org.datanucleus.ObjectManagerImpl.assertIsOpen(ObjectManagerImpl.java:
3876)
at
org.datanucleus.ObjectManagerImpl.getTransaction(ObjectManagerImpl.java:
596)
at
org.datanucleus.jpa.EntityTransactionImpl.isActive(EntityTransactionImpl.java:
61)
at org.datanucleus.jpa.JPAQuery.getResultList(JPAQuery.java:158)
I found here on groups the same error posted with suggestions that
using OpenEntityManagerInViewFilter should keep entity manager
throughout the request. Unforfunately, I can't get this filter working
because it tries to create a new entity manager factory while gae
allows to create only one of those.
Here is part of my web.xml
<servlet>
<servlet-name>context</servlet-name>
<servlet-class>
org.springframework.web.context.ContextLoaderServlet
</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
<filter>
<filter-name>OpenEntityManagerInViewFilter</filter-name>
<filter-
class>org.springframework.orm.jpa.support.OpenEntityManagerInViewFilter</
filter-class>
<init-param>
<param-name>entityManagerFactory</param-name>
<param-value>entityManagerFactory</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>OpenEntityManagerInViewFilter</filter-name>
<url-pattern>*.html</url-pattern>
</filter-mapping>
And part of applicationContext.xml:
<bean id="entityManagerFactory" name="entityManagerFactory"
class="org.springframework.orm.jpa.LocalEntityManagerFactoryBean"
scope="singleton">
<property name="persistenceUnitName"
value="transactions-optional" /
>
</bean>
<bean id="transactionManager"
class="org.springframework.orm.jpa.JpaTransactionManager"
scope="singleton">
<property name="entityManagerFactory"
ref="entityManagerFactory" />
</bean>
And here is the error caused by filter:
org.springframework.web.servlet.FrameworkServlet initServletBean:
Context initialization failed
org.springframework.beans.factory.BeanCreationException: Error
creating bean with name 'entityManagerFactory' defined in
ServletContext resource [/WEB-INF/allewidok-servlet.xml]: Invocation
of init method failed; nested exception is
javax.persistence.PersistenceException: Provider error. Provider:
org.datanucleus.store.appengine.jpa.DatastorePersistenceProvider
(...)
Caused by: java.lang.IllegalStateException: Application code attempted
to create a EntityManagerFactory named transactions-optional, but one
with this name already exists! Instances of EntityManagerFactory are
extremely slow to create and it is usually not necessary to create one
with a given name more than once. Instead, create a singleton and
share it throughout your code. If you really do need to create a
duplicate EntityManagerFactory (such as for a unittest suite), set the
appengine.orm.disable.duplicate.emf.exception system property to avoid
this error.
at
org.datanucleus.store.appengine.jpa.DatastoreEntityManagerFactory.checkForRepeatedAllocation(DatastoreEntityManagerFactory.java:
136)
at
org.datanucleus.store.appengine.jpa.DatastoreEntityManagerFactory.<init>(DatastoreEntityManagerFactory.java:
64)
at
org.datanucleus.store.appengine.jpa.DatastorePersistenceProvider.createEntityManagerFactory(DatastorePersistenceProvider.java:
35)
at javax.persistence.Persistence.createFactory(Persistence.java:172)
So, has anybody actually used OpenEntityManagerInViewFilter on GAE?
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