Making a client-side JPA connection

homaxto · **Joined:** Tue Sep 16, 2008 4:52 am **Posts:** 4

For testing purpose I am trying to make a JPA connection to our database.
I get an error saying:

Code:

Unable to configure EntityManagerFactory

with no further explanation!

I think I have tried everything in my persistence file and now finally I give up.

My persistence.xml (only the persistence-unit):

Code:

<persistence-unit name="Test" transaction-type="RESOURCE_LOCAL">
    <provider>org.hibernate.ejb.HibernatePersistence</provider>
    <class>dme.dm.device.Operation</class>
    <class>dme.dm.device.Action</class>
    <properties>
        <property name="hibernate.connection.driver_class"
                  value="com.mysql.jdbc.Driver"/>
        <property name="hibernate.connection.username"
                  value="jb"/>
        <property name="hibernate.connection.password"
                  value="123"/>
        <property name="hibernate.connection.url"
                  value="jdbc:mysql://127.0.0.1/dm"/>
        <property name="hibernate.dialect"
                  value="org.hibernate.dialect.MySQLDialect"/>
        <property name="hibernate.hbm2ddl.auto"
                  value="update"/>
    </properties>
</persistence-unit>

And I make the call like this:

Code:

public class OperationTest {
    private EntityManager entityManager;

    @Before
    public void setUp() {
        EntityManagerFactory emf = Persistence.createEntityManagerFactory("Test");
        entityManager = emf.createEntityManager();
    }
}

When I run this code I get the exception:

Code:

javax.persistence.PersistenceException: [PersistenceUnit: Test] Unable to configure EntityManagerFactory
   at org.hibernate.ejb.Ejb3Configuration.configure(Ejb3Configuration.java:265)
   at org.hibernate.ejb.HibernatePersistence.createEntityManagerFactory(HibernatePersistence.java:125)

Does anyone have an idea of what could be wrong?

Regards,
Thomas

carlolf · **Posted:** Tue Sep 16, 2008 4:15 pm

Quote:

.. with no further explanation!

really? I suppose you could give us more from the stacktraces. Indeed one cannot see what's going on if we have only these few lines of the stacktrace.

Alternatively, debug into the Hibernate code - if you haven' t the source code, download it and my it available in you favourite IDE - sometimes this is very useful.

homaxto · **Joined:** Tue Sep 16, 2008 4:52 am **Posts:** 4

carlolf your right, there is a further explanation.

Looking deeper into the stacktrace I found this one:
java.lang.NoSuchMethodException:

Code:

org.hibernate.validator.ClassValidator.<init>(...)

I found out that I had jboss libs in my classpath with the same class, but obviously another version. Removing jboss from the classpath made everything spin like a cat.

Funny how many problems one can solve just presenting the problem to others :)

Thanks,
Thomas