Issue with #Transactional annotations in Spring JPA - spring

I have a doubt related to transactions within transactions. For background, I have a School entity object which has Set of Students entity object mapped to it. I am using Spring Data JPA which is taking care of all the crud operations. I have a SchoolManagementService class which has #Transactional(readonly=true) set at the class level and for all updating methods I am using #Transactional over them.
In my SchoolManagementService class I have a method deleteStudents(List) which I have marked as #Transactional. In this method I am calling StudentsRepository.delete(studentId) again and again. I want to make sure if any delete fails then the transaction should rollback for that checked exception. I am trying to test this with my spring junit test case (I am not using default rollback=true or#rollback(true) because I want this to be rollbacked because of some runtime exception I encounter at the repository delete method.
#RunWith(SpringJUnit4ClassRunner.class)
#TestExecutionListeners({DependencyInjectionTestExecutionListener.class, TransactionalTestExecutionListener.class})
#ContextConfiguration(locations = {"classpath:PPLRepository-context.xml"})
public class TestClass{
#Test
#Transactional
public void testDeleteStudents(){
StudentManagementService.delete(randomList)
}
with this testcase it is deleting all the records but the last one. Ideally it should rollback and none of of entries should be deleted.
Here is my sprin settings file with TransactionMangaer configs
<bean id="atomikosTransactionManager" class="com.atomikos.icatch.jta.UserTransactionManager" init-method="init"
destroy-method="close">
<property name="forceShutdown" value="true" />
<property name="startupTransactionService" value="true" />
<property name="transactionTimeout" value="1000" />
</bean>
<bean id="atomikosUserTransaction" class="com.atomikos.icatch.jta.UserTransactionImp" />
<!-- Configure the Spring framework to use JTA transactions from Atomikos -->
<bean id="transactionManager" class="org.springframework.transaction.jta.JtaTransactionManager">
<property name="transactionManager" ref="atomikosTransactionManager" />
<property name="userTransaction" ref="atomikosUserTransaction" />
<property name="transactionSynchronizationName" value="SYNCHRONIZATION_ON_ACTUAL_TRANSACTION" />
</bean>
<!-- EntityManager Factory that brings together the persistence unit, datasource, and JPA Vendor -->
<bean class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean" id="PPL_GMR">
<property name="dataSource" ref="PPL_GMRDS"></property>
<property name="persistenceUnitName" value="PPL_GMR"/>
<property name="persistenceXmlLocation" value="classpath:META-INF/PPL-persistence.xml"/>
<property name="jpaVendorAdapter" ref="PPL_GMRJPAVendorAdapter"/>
<property name="jpaPropertyMap">
<map>
<entry key="hibernate.transaction.manager_lookup_class" value="com.atomikos.icatch.jta.hibernate3.TransactionManagerLookup"/>
<entry key="hibernate.connection.release_mode" value="on_close"/>
<entry key="hibernate.default_schema" value="${PPL.schema}"/>
</map>
</property>
</bean>
Can someone suggest where my understanding of transactions is wrong? Whatever I have read from the APIs I got this impression that if some method is #Transactional at the service layer and if it calls several #Transactional methods of Spring Data JPA repositories then if I encounter any Runtime exception then all the transactions should be rolled back.
I even tried to simple create a testcase method as below:
#Test
#Transactional
public void testDeleteStudents(){
StudentRepository.delete(1);
StudentRepository.delete(2);// 2 id is not present so I will get a runtime exception.
}
Inspite of keeping #Rollback(true/false) on this method, this method deletes id 1 Student from the database. I thought that #Transactional at this testcase method will create a new transaction here and all the transactional delete methods from the StudentRepository will run in same transaction. And no student data will be committed until and unless no runtime exception is thrown.
Please help me understand transactions better as I am new to this. i am using Spring Data JPA with Oracle database.
Thanks in advance.

I think that the default behaviour is (even thought you don't have it on the test class)
#TransactionConfiguration(defaultRollback = true)
so it will perform rollback when your test ends. Therefore there is no synchronization of hibernate session with the database and no queries SQL are issued to the database.
You have two posibilities. Either specify
#TransactionConfiguration(defaultRollback = false)
or inject entity manager into your test and call
#PersistenceContext
protected EntityManager em;
/**
* Simulates new transaction (empties Entity Manager cache).
*/
public void simulateNewTransaction() {
em.flush();
em.clear();
}
This will force hibernate to send all queries to the database. Please note that this will solve your problem with deleting non existing entity, but it doesn't behave exactly like new transaction, e.g. when you have missing foreign key it doesn't throw anything (this is predictable.
You can use this for checking the contents of entity returned by em.find(class, id) and check you relational mapping without the need to commit the transaction.

Related

Hibernate Transaction Manager not committing data changes

I'm using Hibernate 4 to write data to an H2 embedded in-memory database and there seems to be a problem with transactions. The application already uses Oracle and H2 has been added with a separate DataSource, SessionFactory, and TransactionManager. The original TransactionManager is marked as default and the H2 TransactionManager has the qualifier memTransactions
The following code - specifically the load function - correctly populates the memEvents variable at the end with the written data.
#Repository
#Transactional(transactionManager = "memTransactions")
public class EventMemDaoHibernate implements EventMemDao {
#Autowired
#Qualifier(value = "memSessionFactory")
private SessionFactory memSessionFactory;
#Override
public List<EventMem> getEvents() {
return memSessionFactory.getCurrentSession().createCriteria(EventMem.class).list();
}
#Override
public void load(List<Event> allEvents) {
Session session = memSessionFactory.getCurrentSession();
for (Event e : allEvents) {
EventMem memEvent = new EventMem(e);
session.save(memEvent);
}
List<EventMem> memEvents = getEvents(); // correct
}
}
However the following code produces an empty memEvents list
#Autowired
private EventMemDao eventMemDao;
List<Event> allEvents = eventDao.getAllEvents();
eventMemDao.load(allEvents); // calls the load function shown above
List<EventMem> memEvents = eventMemDao.getEvents(); // empty
I assume this is related to transaction management (e.g.: data is not auto-committed after the call to .save()). However when I tried explicitly beginning and committing a transaction within EventMemDaoHibernate#load, I receive this error:
nested transactions not supported
So, from what I can tell the TransactionManager is working.
My TransactionManager and related bean definitions are shown below.
<bean
id="memTransactionManager"
class="org.springframework.orm.hibernate4.HibernateTransactionManager">
<property name="sessionFactory" ref="memSessionFactory" />
<qualifier value="memTransactions"/>
</bean>
<bean id="hDataSource" class="org.h2.jdbcx.JdbcDataSource">
<property name="url" value="jdbc:h2:mem:db1;DB_CLOSE_DELAY=-1;INIT=RUNSCRIPT FROM 'classpath:scripts/init-h2.sql'" />
<property name="user" value="sa" />
<property name="password" value="" />
</bean>
<bean
id="memSessionFactory"
class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
<property name="dataSource" ref="hDataSource" />
<property name="hibernateProperties">
<props>
<prop key="hibernate.dialect">org.hibernate.dialect.H2Dialect</prop>
</props>
</property>
</bean>
This was due to my configuration error (of course). I didn't fully grasp that the connection URL was evaluated every time a session was opened against H2 and that means init-h2.sql was executed repeatedly. init-h2.sql included a truncate followed by an insert so it was dropping and recreating data every time Hibernate opened a session.

Spring transaction propogation on non spring managed beans

I am working on a migration project which involves upgrading the platform to Spring 4 with MyBatis. In the legacy code, transactions are handled at a central locations wherein call to start/end transactions are spread across various classes like service class, helper class and DAO class.
I managed to convert all service classes to spring managed component and DAO classes to support MyBatis-spring API. Problem is my service class use several other classes to perform a function and those classes are all instantiated manually and used. Now if i start a transaction on service class methods and perform database transactions inside other helper or DAO classes which are not spring managed, my transaction handling doesn't work correctly. I have illustrated this problem in the below code. Could you tell what are the ways to acheive transaction handling without modifying the code?
Example :
package com.service;
#Service
class MyService {
#Transactional( propagation=Propagation.REQUIRED)
public void processRequest () {
HelperClass helper = new HelperClass();
helper.performOperation();
}
}
package com.helper;
// this class is not spring bean
class HelperClass {
// MyBatis mapper class
private EmployeeMapper mapper;
public HelperClass () {
mapper = // retrieve mapper class bean from spring context
}
public performOperation () {
// call to mapper class insert operation
// call to mapper class update operation
}
}
package com.dao;
#Component
interface EmployeeMapper {
// method definition to perform database operation
}
Spring configuration details:
<context:component-scan base-package="com" />
<bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource" destroy-method="close">
....
....
</bean>
<bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
<property name="dataSource" ref="dataSource" />
</bean>
<tx:annotation-driven transaction-manager="transactionManager" mode="aspectj" />
<mybatis:scan base-package="com.dao" />
<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
<property name="dataSource" ref="dataSource" />
<property name="mapperLocations"
value="classpath*:mybatis/*.xml" />
</bean>
In the above code HelperClass.performOperation() method is doing 2 database operations (insert,update). Say if insert succeeds and update fails, my database transaction doesn't get rollback. Since I already started the transaction at MyService.processRequest() should this not rollback the operations that are carried inside that method call? Correct me if my understanding is wrong.

transactions not working with Spring 3.1 – H2 – junit 4– hibernate 3.2

I have the following test..
#RunWith(SpringJUnit4ClassRunner.class)
#ContextConfiguration(locations = {"/schedule-agents-config-context.xml"})
#TransactionConfiguration(transactionManager = "transactionManager", defaultRollback = true)
#Transactional
public class H2TransactionNotWorkingTest extends SubmitAgentIntegratedTestBase {
private static final int FIVE_SUBMISSIONS = 5;
#Autowired
private ApplicationSubmissionInfoDao submissionDao;
private FakeApplicationSubmissionInfoRepository fakeRepo;
#Before
public void setUp() {
fakeRepo = fakeRepoThatNeverFails(submissionDao, null);
submitApplication(FIVE_SUBMISSIONS, fakeRepo);
}
#Test
#Rollback(true)
public void shouldSaveSubmissionInfoWhenFailureInDatabase() {
assertThat(fakeRepo.retrieveAll(), hasSize(FIVE_SUBMISSIONS));
}
#Test
#Rollback(true)
public void shouldSaveSubmissionInfoWhenFailureInXmlService() {
assertThat(fakeRepo.retrieveAll().size(), equalTo(FIVE_SUBMISSIONS));
}
}
...and the following config...
<jdbc:embedded-database id="dataSource" type="H2">
<jdbc:script location="classpath:/db/h2-schema.sql" />
</jdbc:embedded-database>
<tx:annotation-driven transaction-manager="transactionManager"/>
<bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
<property name="dataSource" ref="dataSource"/>
</bean>
<bean id="transactionalSessionFactory"
class="org.springframework.orm.hibernate3.annotation.AnnotationSessionFactoryBean">
<property name="dataSource" ref="dataSource"/>
<property name="hibernateProperties">
<props>
<prop key="hibernate.dialect">org.hibernate.dialect.H2Dialect</prop>
<prop key="hibernate.show_sql">false</prop>
<prop key="hibernate.cache.use_second_level_cache">false</prop>
<prop key="hibernate.cache.use_query_cache">false</prop>
</props>
</property>
<property name="namingStrategy">
<bean class="org.hibernate.cfg.ImprovedNamingStrategy"/>
</property>
<property name="configurationClass" value="org.hibernate.cfg.AnnotationConfiguration"/>
<property name="packagesToScan" value="au.com.mycomp.life.snapp"/>
</bean>
<bean id="regionDependentProperties" class="org.springframework.core.io.ClassPathResource">
<constructor-arg value="region-dependent-service-test.properties"/>
</bean
>
I have also set auto commit to false in the sql script
SET AUTOCOMMIT FALSE;
There are not REQUIRES_NEW in the code.
Why is the rollback not working in the test?
Cheers
Prabin
I have faced the same problem but I have finally solved it albeit I don't use Hibernate (shouldn't really matter).
The key item making it work was to extend the proper Spring unit test class, i.e. AbstractTransactionalJUnit4SpringContextTests. Note the "Transactional" in the class name. Thus the skeleton of a working transactional unit test class looks like:
#ContextConfiguration(locations = {"classpath:/com/.../testContext.xml"})
public class Test extends AbstractTransactionalJUnit4SpringContextTests {
#Test
#Transactional
public void test() {
}
}
The associated XML context file has the following items contained:
<jdbc:embedded-database id="dataSource" type="H2" />
<tx:annotation-driven transaction-manager="transactionManager"/>
<bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
<property name="dataSource" ref="dataSource"></property>
</bean>
Using this setup the modifications by each test method is properly rolled back.
Regards, Ola
I'm experiencing similar problems, I'm also using TestNG + Spring test support and Hibernate. What happens is that Hibernate disables autocommit on the connection before the transaction begins and it remembers the original autocommit setting:
org.hibernate.engine.transaction.internal.jdbc#JdbcTransaction:
#Override
protected void doBegin() {
try {
if ( managedConnection != null ) {
throw new TransactionException( "Already have an associated managed connection" );
}
managedConnection = transactionCoordinator().getJdbcCoordinator().getLogicalConnection().getConnection();
wasInitiallyAutoCommit = managedConnection.getAutoCommit();
LOG.debugv( "initial autocommit status: {0}", wasInitiallyAutoCommit );
if ( wasInitiallyAutoCommit ) {
LOG.debug( "disabling autocommit" );
managedConnection.setAutoCommit( false );
}
}
catch( SQLException e ) {
throw new TransactionException( "JDBC begin transaction failed: ", e );
}
isDriver = transactionCoordinator().takeOwnership();
}
Later on, after rolling back the transaction, it will release the connection. Doing so hibernate will also restore the original autocommit setting on the connection (so that others who might be handed out the same connection start with the original setting). However, setting the autocommit during a transaction triggers an explicit commit, see JavaDoc
In the code below you can see this happening. The rollback is issued and finally the connection is released in releaseManagedConnection. Here the autocommit will be re-set which triggers a commit:
org.hibernate.engine.transaction.internal.jdbc#JdbcTransaction:
#Override
protected void doRollback() throws TransactionException {
try {
managedConnection.rollback();
LOG.debug( "rolled JDBC Connection" );
}
catch( SQLException e ) {
throw new TransactionException( "unable to rollback against JDBC connection", e );
}
finally {
releaseManagedConnection();
}
}
private void releaseManagedConnection() {
try {
if ( wasInitiallyAutoCommit ) {
LOG.debug( "re-enabling autocommit" );
managedConnection.setAutoCommit( true );
}
managedConnection = null;
}
catch ( Exception e ) {
LOG.debug( "Could not toggle autocommit", e );
}
}
This should not be a problem normally, because afaik the transaction should have ended after the rollback. But even more, if I issue a commit after a rollback it should not be committing any changes if there were no changes between the rollback and the commit, from the javadoc on commit:
Makes all changes made since the previous commit/rollback permanent
and releases any database locks currently held by this Connection
object. This method should be used only when auto-commit mode has been
disabled.
In this case there were no changes between rollback and commit, since the commit (triggered indirectly by re-setting autocommit) happens only a few statements later.
A work around seems to be to disable autocommit. This will avoid restoring autocommit (since it was not enabled in the first place) and thus prevent the commit from happening. You can do this by manipulating the id for the embedded datasource bean. The id is not only used for the identification of the datasource, but also for the databasename:
<jdbc:embedded-database id="dataSource;AUTOCOMMIT=OFF" type="H2"/>
This will create a database with name "dataSource". The extra parameter will be interpreted by H2. Spring will also create a bean with name "dataSource;AUTOCOMMIT=OFF"". If you depend on the bean names for injection, you can create an alias to make it cleaner:
<alias name="dataSource;AUTOCOMMIT=OFF" alias="dataSource"/>
(there isn't a cleaner way to manipulate the embedded-database namespace config, I wish Spring team would have made this a bit better configurable)
Note: disabling the autocommit via the script (<jdbc:script location="...") might not work, since there is no guarantee that the same connection will be re-used for your test.
Note: this is not a real fix but merely a workaround. There is still something wrong that cause the data to be committed after a rollback occured.
----EDIT----
After searching I found out the real problem. If you are using HibernateTransactionManager (as I was doing) and you use your database via the SessionFactory (Hibernate) and directly via the DataSource (plain JDBC), you should pass both the SessionFactory and the DataSource to the HibernateTransactionManager. From the Javadoc:
Note: To be able to register a DataSource's Connection for plain JDBC code, this instance >needs to be aware of the DataSource (setDataSource(javax.sql.DataSource)). The given >DataSource should obviously match the one used by the given SessionFactory.
So eventually I did this:
<bean id="transactionManager" class="org.springframework.orm.hibernate4.HibernateTransactionManager">
<property name="sessionFactory" ref="sessionFactory" />
<property name="dataSource" ref="dataSource" />
</bean>
And everything worked for me.
Note: the same goes for JpaTransactionManager! If you both use the EntityManager and perform raw JDBC access using the DataSource, you should supply the DataSource separately next to he EMF. Also don't forget to use DataSourecUtils to obtain a connection (or JDBCTemplate which uses DataSourceUtils internally to obtain the connection)
----EDIT----
Aight, while the above did solve my problem, it is not the real cause after all :)
In normal cases when using Spring's LocalSessionFactoryBean, setting the datasource will have no effect since it's done for you.
If the SessionFactory was configured with LocalDataSourceConnectionProvider, i.e. by Spring's LocalSessionFactoryBean with a specified "dataSource", the DataSource will be auto-detected: You can still explicitly specify the DataSource, but you don't need to in this case.
In my case the problem was that we created a caching factory bean that extended LocalSessionFactoryBean. We only use this during testing to avoid booting the SessionFactory multiple times. As told before, Spring test support does boot multiple application contexts if the resource key is different. This caching mechanism mitigates the overhead completely and ensures only 1 SF is loaded.
This means that the same SessionFactory is returned for different booted application contexts. Also, the datasource passed to the SF will be the datasource from the first context that booted the SF. This is all fine, but the DataSource itself is a new "object" for each new application context. This creates a discrepancy:
The transaction is started by the HibernateTransactionManager. The datasource used for transaction synchronization is obtained from the SessionFactory (so again: the cached SessionFactory with the DataSource instance from the application context the SessionFactory was initially loaded from). When using the DataSource in your test (or production code) directly, you'll be using the instance belonging to the app context active at that point. This instance does not match the instance used for the transaction synchronization (extracted from the SF). This result into problems as the connection obtained will not be properly participating in the transaction.
By explicitly setting the datasource on the transactionmanager this appeared to be solved since the post initialization will not obtain the datasource from the SF but use the injected one instead. The appropriate way for me was to adjust the caching mechanism and replace the datasource in the cached SF with the one from the current appcontext each time the SF was returned from cache.
Conclusion: you can ignore my post:) as long as you're using HibernateTransactionManager or JtaTransactionManager in combination with some kind of Spring support factory bean for the SF or EM you should be fine, even when mixing vanilla JDBC with Hibernate. In the latter case don't forget to obtain connections via DataSourceUtils (or use JDBCTemplate).
Try this:
remove the org.springframework.jdbc.datasource.DataSourceTransactionManager
<bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
<property name="dataSource" ref="dataSource"/>
</bean>
and replace it with the org.springframework.orm.jpa.JpaTransactionManager
<bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
<property name="dataSource" ref="dataSource"/>
</bean>
or you inject an EntityManagerFactory instead ...
<bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
<property name="entityManagerFactory" ref="entityManagerFactory" />
</bean>
you need an EntityManagerFactory then, like the following
<bean id="entityManagerFactory"
class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
<property name="dataSource" ref="dataSource" />
<property name="jpaVendorAdapter">
<bean id="jpaAdapter"
class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter">
<property name="showSql" value="true" />
<property name="generateDdl" value="true" />
</bean>
</property>
</bean>
You haven't shown all the pieces to the puzzle. My guess at this point would be that your ApplicationSubmissionInfoDao is transactional and is committing on its own, though I'd think that would conflict with the test transactions if everything were configured properly. To get more of an answer, ask a more complete question. The best thing would be to post an SSCCE.
Thanks Ryan
The test code is something like this.
#Test
#Rollback(true)
public void shouldHave5ApplicationSubmissionInfo() {
for (int i = 0; i < 5; i++) {
hibernateTemplate.saveOrUpdate(new ApplicationSubmissionInfoBuilder()
.with(NOT_PROCESSED)
.build());
}
assertThat(repo.retrieveAll(), hasSize(5));
}
#Test
#Rollback(true)
public void shouldHave5ApplicationSubmissionInfoAgainButHas10() {
for (int i = 0; i < 5; i++) {
hibernateTemplate.saveOrUpdate(new ApplicationSubmissionInfoBuilder()
.with(NOT_PROCESSED)
.build());
}
assertThat(repo.retrieveAll(), hasSize(5));
}
I figure out that embedded DB define using jdbc:embedded-database don't have transaction support. When I used commons DBCP to define the datasource and set default auto commit to false, it worked.
<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" scope="singleton">
<property name="driverClassName" value="org.h2.Driver" />
<property name="url" value="jdbc:h2:~/snappDb"/>
<property name="username" value="sa"/>
<property name="password" value=""/>
<property name="defaultAutoCommit" value="false" />
<property name="connectionInitSqls" value=""/>
</bean>
None of the above worked for me!
However, the stack i am using is [spring-test 4.2.6.RELEASE, spring-core 4.2.6.RELEASE, spring-data 1.10.1.RELEASE]
The thing is, using any unit test class annotated with [SpringJUnit4ClassRunner.class] will result in an auto-rollback functionality by spring library design
check ***org.springframework.test.context.transaction.TransactionalTestExecutionListener*** >> ***isDefaultRollback***
To overcome this behavior just annotate the unit test class with
#Rollback(value = false)

What's the link between #Transactional and cascading?

There seems to be a link between the presence of the #Transactional annotation on a Spring JUnit test and cascading when persisting/merging a JPA2 entity.
I don't have the configuration at hand for the moment, but maybe this rings a bell to somebody in here ?
Assume a simple case of JPA entities on three levels: Entity A references an entity of class B and that instance of class B references an instance of class C.
A -> B -> C
Class A does cascading ALL to B. And B does cascading ALL to C. And Class C has an event listener method annotated with #PrePersist and #PreUpdate. It logs a message to prove the cascading made it to there.
Now, modify entity C in some way and ask the entity manager to merge or persist the instance of A. Logically entity C will eventually be persisted or merged also. Because of cascading has been set to ALL from class A to B to C.
When the Spring unit test is not annotated with #Transactional, the log message from the event listener method of class C prints its message. OK.
But when it is annotated with #Transactional, no message at all is printed. And indeed, nothing has been committed to the database for class C. Only for class A. Hence, I conclude the cascading didn't make it from A to C.
Removing the annotation fixes the problem.
Anybody any clue? :-) Logically I would think transactions and cascading are two totally separated matters.
A typical test case configuration:
#RunWith(SpringJUnit4ClassRunner.class)
#ContextConfiguration("/test-beans.xml")
#TransactionConfiguration
#Transactional
public class MyUnitTest {
...
#Test
public void testSomething() {}
...
}
An extract of the Spring xml configuration file - nothing fancy there I think ...
<context:annotation-config />
<tx:annotation-driven transaction-manager="transactionManager" />
<context:component-scan base-package="com.foo.bar" />
<bean id="jpaTemplate" class="org.springframework.orm.jpa.JpaTemplate">
<property name="entityManagerFactory" ref="entityManagerFactory" />
</bean>
<bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
<property name="persistenceXmlLocation" value="/META-INF/persistence.xml"/>
<property name="persistenceUnitName" value="bar" />
</bean>
<bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
<property name="entityManagerFactory" ref="entityManagerFactory" />
</bean>
Extract from persistence.xml
<persistence-unit name="bar" transaction-type="RESOURCE_LOCAL">
<provider>org.hibernate.ejb.HibernatePersistence</provider>
<properties>
<property name="hibernate.connection.driver_class" value="com.mysql.jdbc.Driver" />
<property name="hibernate.connection.url" value="jdbc:mysql://localhost:3306/bar" />
<property name="hibernate.connection.username" value="bar" />
<property name="hibernate.connection.password" value="pwd" />
<property name="hibernate.cache.provider_class" value="org.hibernate.cache.NoCacheProvider"/>
<property name="hibernate.hbm2ddl.auto" value="create"/>
<property name="dialect" value="org.hibernate.dialect.MySQLDialect" />
</properties>
</persistence-unit>
Libraries
Spring 3.0.6 ORM/CONTEXT/TEST
Hibernate 3.6.7.Final
JUnit 4.9
JPA2
Found it ! An improper entity manager usage was turning bad when transactions were enabled. It wasn't related to the persistence but was done right before it. Causing the persistence to fail in some way.
I implemented a Query result iterator for which an EntityManager was required. I thought I could create it from the EntityManagerFactory of the jpaTemplate.
final EntityManager em = jpaTemplate.getEntityManagerFactory().createEntityManager();
return new QueryIterator<T>(em.createQuery("FROM Foo"));
Obviously not. It seems the EntityManager has to be obtained in a different way. As described underneath.
jpaTemplate.execute(new JpaCallback() {
#Override
public Object doInJpa(final EntityManager em) throws PersistenceException {
return new QueryIterator<T>(em.createQuery("FROM Foo"));
}
});
Now it all works ok. As it is supposed to be, regardless of transactions being present or not. :-)

Datanucleus: moving from #Transactional to non-transactional

I am using Datanucleus, JDO and Spring's declarative #Transactional management woven with Aspect-J.
But when a 'normal' method gets a persistent object from a #Transactional method, the object's state will become transient (the persistence manager seems to be removed) and the object is no longer persistent.
Example:
public class Example {
public void test() throws Exception {
Login l = getLogin();
JDOHelper.getObjectState(l); // transient instead of persistent
l.getSomeOtherPersistentObj().doStuff(); // NullpointerException :(
}
#Transactional
private Login getLogin() {
// do transactional stuff here
// ..
return dao.find(Login.class, 1);
}
}
Why is this and how can I fix it without adding #Transactional in places where transactions are not needed? The following does (obviously) work so this indicates that a transactional as well as a non-transactional connection can be made:
A #Transactional method calls a #Transactional method
A #Transactional method calls a normal method
A normal method calls a normal method
If I call dao.refresh(l), I get: 'Object with id "" is managed by a different Object Manager', so maybe Spring is working on a different persistence manager than the DAO, is this the cause?
Here's my spring configuration (it might be relevant):
<bean id="pmf" class="org.datanucleus.api.jdo.JDOPersistenceManagerFactory" destroy-method="close">
<property name="connectionDriverName" value="com.mysql.jdbc.Driver"/>
...
<constructor-arg>
<map>
<entry key="datanucleus.autoCreateSchema" value="true" />
</map>
</constructor-arg>
</bean>
<bean id="myPmfProxy" class="org.springframework.orm.jdo.TransactionAwarePersistenceManagerFactoryProxy">
<property name="targetPersistenceManagerFactory" ref="pmf" />
</bean>
<bean id="transactionManager" class="org.springframework.orm.jdo.JdoTransactionManager">
<property name="persistenceManagerFactory" ref="myPmfProxy" />
</bean>
<bean id="JDODao" class="sw.JDODao">
<property name="persistenceManagerFactory" ref="myPmfProxy" />
</bean>
It turned out that my objects need to be detachable to do this.
Iv'e added (detachable="true") to my #PersistenceCapable annotations and set the following datanucleus options:
<entry key="datanucleus.DetachAllOnCommit" value="true" />
<entry key="datanucleus.detachedState" value="all" />

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