Hi,

Since I had some problems getting Envers to work with our Spring project, I though I'd share my notes with you. Additionally I had some "fun" in getting it to work with Oracle. I generated the version schema by hand.

Setup:

- Spring 2.5.6
- Hibernate 3.2.6
- Envers 1.1.0-GA

We are using Hibernate directly without using JPA, so the standard configuration does not apply, here is what you need to do:

in your applicationContext.xml add:

<!-- Event listener for the Envers auditing framework, see sessionFactory configuration -->
 <bean id="versionsEventListener" class="org.jboss.envers.event.VersionsEventListener" />

in your sessionFactory bean add:

<property name="eventListeners">
 <map>
 <entry key="post-insert" value-ref="versionsEventListener" />
 <entry key="post-update" value-ref="versionsEventListener" />
 <entry key="post-delete" value-ref="versionsEventListener" />
 <entry key="pre-collection-update" value-ref="versionsEventListener" />
 <entry key="pre-collection-remove" value-ref="versionsEventListener" />
 <entry key="post-collection-recreate" value-ref="versionsEventListener" />
 </map>
 </property>

Since Oracle does not like names to begin with an underscore we need to add two more properties to the hibernateProperties of your sessionFactory, see also
http://www.jboss.org/envers/configuration.html
and
http://www.jboss.org/envers/conf_oracle.html

<property name="hibernateProperties">
 <props>
 <prop key="org.jboss.envers.revisionTypeFieldName">VER_REV_TYPE</prop>
 <prop key="org.jboss.envers.revisionFieldName">VER_REV</prop>
 </props>
 </property>

Finally, we need to rename the default revisions info table, since its name starts with an underscore and Oracle does not like that, this can be achieved by introducing a custom RevisionEntity which extends DefaultRevisionEntity:

/**
 * Oracle doesn't like the default revisions entity table name (_revisions_info, Oracle doesn't allow names to start
 * with '_')
 *
 */
@Entity
@RevisionEntity
public class OracleRevisionEntity extends DefaultRevisionEntity {
 // should be empty
}

Debugging note: when Envers can't save data in a version table you won't see an exception in your console, however when you look in your hibernate log file (enable DEBUG) you'll see what is going on.


Cheers,
Marc.