Unit tests and LazyInitializationException

[camach]

I'm using Hibernate & Spring and I'm looking for some best practices for writing unit tests. I'm currently getting a LazyInitializationException when executing this unit test:

public void testUserInRoleOk() throws Exception {
		
		WebUser user = this.userService.retrieveWebUser("johndoe@yahoo.com", "password");
		assertTrue(this.userService.isUserInRole(user, WebRoleEnum.CUSTOMER));		
	}

The first line executes ok but then the exception is thrown in the implementation of "isUserInRole".

The WebUser object has a Hibernate relationship with WebRole, there's a WebUser.getWebRoles method that returns a Set of WebRoles and that is exactly what the "isUserInRole" method is doing (and then getting the exception).

I'm using a HibernateTransactionManager and TransactionInterceptor for both methods on the service:"retrieveWebUser" and "isUserInRole".

Now when I deploy this on a web app I guess I would use the OpenSessionInViewInterceptor but what about for unit tests? Is there an elegant way to have a Session stay open for the duration of the test method? I have a feeling I may be missing something.

Thanks
Andres

[irbouho]

You need to simulate the OpenSessionInViewInterceptor behaviour in your Unit Tests.
I use the following class for Spring/Hibernate/JUnit tests

//Hibernate imports
import net.sf.hibernate.FlushMode;
import net.sf.hibernate.Session;
import net.sf.hibernate.SessionFactory;

//Spring imports
import org.springframework.orm.hibernate.SessionFactoryUtils;
import org.springframework.orm.hibernate.SessionHolder;
import org.springframework.transaction.support.TransactionSynchronizationManager;

//Taha imports
import org.taha.spring.BaseSpringTest;

/**
 * @author <a href="mailto:irbouh@videotron.ca">Omar Irbouh</a>
 * @version 0.1
 * @since 2004.03.03
 */
public abstract class BaseSpringHibernateTest extends BaseSpringTest {

  protected static final String SESSION_FACTORY = "sessionFactory";

  protected SessionFactory sessionFactory = null;

  protected void setUp() throws Exception {
    super.setUp();
    sessionFactory = (SessionFactory) getApplicationContext().getBean(SESSION_FACTORY);
    Session session = SessionFactoryUtils.getSession(sessionFactory, true);
    session.setFlushMode(FlushMode.NEVER);
    TransactionSynchronizationManager.bindResource(sessionFactory, new SessionHolder(session));
  }

  protected void tearDown() throws Exception {
    SessionHolder sessionHolder = (SessionHolder) TransactionSynchronizationManager.unbindResource(sessionFactory);
    SessionFactoryUtils.closeSessionIfNecessary(sessionHolder.getSession(), sessionFactory);
    super.tearDown();
  }
}

org.taha.spring.BaseSpringTest is a simillar abstract class responsible for building the ApplicatinContext. You can remove the dependance on BaseSpringTest and add a method getApplicationContext() that returns the ApplicationContext.

HTH.

[camach]

Thanks! I also found a reference on the Hibernate boards:

http://forum.hibernate.org/viewtopic.php?t=929167

The example posted there does not have the line:

session.setFlushMode(FlushMode.NEVER);

Just curious on your thoughts on how FlushMode affects things.

[irbouho]

Good point!!!

I use BaseSpringHibernateTest mainly in readonly + lazy initialization scenarios. I added this line to enforce no updates can be executed in the underlying code.

Now that Jüergen added checkWriteOperationAllowed in HibernateTemplate, I no longer need to keep this line, and the class may serve for readonly/readwrite tests. So, please remove it if you want to use the class in your tests.