Event listeners

mcbi4kh2 · **Joined:** Thu Jun 12, 2008 10:48 am **Posts:** 24

I am trying to log when an object is commited to the db,

I have this class:

Code:

public class LogListener implements PreInsertEventListener, PreUpdateEventListener
{
  public boolean onPreUpdate(PreUpdateEvent aEvent)
  {
    //code
  }
   public boolean onPreInsert(PreInsertEvent aEvent)
  {
    //code
  }
}

In my web.xml I have the follwing lines of config:

Code:

<hibernate-configuration>
  <session-factory>
    <event type="save">
       <listener class="mycompany.data.LogListener"/>
    </event>
        <event type="update">
       <listener class="mycompany.data.LogListener"/>
    </event>
  </session-factory>
</hibernate-configuration>

Now when I execute a saveOrUpdate method in one of my dao's the onPreUpdate / onPreInsert methods are not being called. Am I missing something?[/code]

mmerder · **Posted:** Wed Feb 18, 2009 9:36 am

Try to use event type names like "pre-update" or "pre-insert"

mcbi4kh2 · **Joined:** Thu Jun 12, 2008 10:48 am **Posts:** 24

Thanks for the suggestion, I tried it but it is still not going in the method. It is now

Code:

<hibernate-configuration>
  <session-factory>
    <event type="pre-insert">
       <listener class="uk.co.data.AuditLogListener"/>
    </event>
        <event type="pre-update">
       <listener class="uk.co.data.AuditLogListener"/>
    </event>
  </session-factory>
</hibernate-configuration>

mmerder · **Posted:** Wed Feb 18, 2009 9:50 am

Are you also using a persistence.xml? In that case you have either to include the listeners or your hibernate.cfg.xml.

Why do you configure hibernate in web.xml?

mcbi4kh2 · **Joined:** Thu Jun 12, 2008 10:48 am **Posts:** 24

No I'm not using a presistence.xml, should I be?

I point my web.xml to read the myProject-db.xml file which has all my dataSource, sessionFactory, hibernateTemplate beans in.

I tried putting my listeners in there but I get an error saying "Element type 'listener' must be declared".

mmerder · **Posted:** Wed Feb 18, 2009 10:00 am

hmm, i have no clue about your project structure. Can you post your structure or your myProject-db.xml? Where did you get that structure from? Any tutorial where you copied it from?

mcbi4kh2 · **Joined:** Thu Jun 12, 2008 10:48 am **Posts:** 24

Ok Im using Spring MVC and Hibernate to do a web app.

I have my web.xml which has:

Code:

  <!--  Spring Context Loaders -->
  <listener>
    <listener-class>
      org.springframework.web.context.ContextLoaderListener
    </listener-class>
  </listener>



  <context-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>
      /WEB-INF/myProject-security.xml,
      classpath:/config/myProject-dao.xml,
      classpath:/config/myProject-db.xml,
      classpath:/config/myProject-services.xml,

    </param-value>
  </context-param>

In myProject-dao.xml I just hava

Code:

<beans>

  <bean id="dao" abstract="true">
    <property name="hibernateTemplate">
      <ref bean="hibernateTemplate" />
    </property>
  </bean>
  <bean id="myDao" parent="dao" class="myCompany.etc"/>

In myProject-db.xml I have the hibernate config stuff

Code:

  <!-- Properties Configuration -->
  <bean id="propertyConfigurer"
    class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
    <property name="locations">
      <list>
        <value>
          classpath:config/myProject-hibernate.properties
        </value>
      </list>
    </property>
  </bean>

  <bean id="dataSource"
    class="org.apache.commons.dbcp.BasicDataSource">
    <property name="url" value="${myProject.connection.url}" />
    <property name="driverClassName"
      value="${myProject.connection.driver_class}" />
     etc
   </bean>

I'm unsure where I need to put my listeners?

mcbi4kh2 · **Joined:** Thu Jun 12, 2008 10:48 am **Posts:** 24

kochcp · **Posted:** Wed Feb 18, 2009 10:16 am

check to be sure you are registering them correctly.

Code:

EventListeners myListeners = ((SessionFactoryImpl) sessionFactory).getEventListeners();

see the available methods on here to check the various event listener types that are implemented.

http://www.hibernate.org/hib_docs/v3/ap ... eners.html

as for the various EventListener name types, they are available in the EventListeners.java file which goes like:

Code:

      eventInterfaceFromType.put("auto-flush", AutoFlushEventListener.class);
      eventInterfaceFromType.put("merge", MergeEventListener.class);
      eventInterfaceFromType.put("create", PersistEventListener.class);
      eventInterfaceFromType.put("create-onflush", PersistEventListener.class);
      eventInterfaceFromType.put("delete", DeleteEventListener.class);
      eventInterfaceFromType.put("dirty-check", DirtyCheckEventListener.class);
      eventInterfaceFromType.put("evict", EvictEventListener.class);
      eventInterfaceFromType.put("flush", FlushEventListener.class);
      eventInterfaceFromType.put("flush-entity", FlushEntityEventListener.class);
      eventInterfaceFromType.put("load", LoadEventListener.class);
      eventInterfaceFromType.put("load-collection", InitializeCollectionEventListener.class);
      eventInterfaceFromType.put("lock", LockEventListener.class);
      eventInterfaceFromType.put("refresh", RefreshEventListener.class);
      eventInterfaceFromType.put("replicate", ReplicateEventListener.class);
      eventInterfaceFromType.put("save-update", SaveOrUpdateEventListener.class);
      eventInterfaceFromType.put("save", SaveOrUpdateEventListener.class);
      eventInterfaceFromType.put("update", SaveOrUpdateEventListener.class);
      eventInterfaceFromType.put("pre-load", PreLoadEventListener.class);
      eventInterfaceFromType.put("pre-update", PreUpdateEventListener.class);
      eventInterfaceFromType.put("pre-delete", PreDeleteEventListener.class);
      eventInterfaceFromType.put("pre-insert", PreInsertEventListener.class);
      eventInterfaceFromType.put("pre-collection-recreate", PreCollectionRecreateEventListener.class);
      eventInterfaceFromType.put("pre-collection-remove", PreCollectionRemoveEventListener.class);
      eventInterfaceFromType.put("pre-collection-update", PreCollectionUpdateEventListener.class);
      eventInterfaceFromType.put("post-load", PostLoadEventListener.class);
      eventInterfaceFromType.put("post-update", PostUpdateEventListener.class);
      eventInterfaceFromType.put("post-delete", PostDeleteEventListener.class);
      eventInterfaceFromType.put("post-insert", PostInsertEventListener.class);
      eventInterfaceFromType.put("post-commit-update", PostUpdateEventListener.class);
      eventInterfaceFromType.put("post-commit-delete", PostDeleteEventListener.class);
      eventInterfaceFromType.put("post-commit-insert", PostInsertEventListener.class);
      eventInterfaceFromType.put("post-collection-recreate", PostCollectionRecreateEventListener.class);
      eventInterfaceFromType.put("post-collection-remove", PostCollectionRemoveEventListener.class);
      eventInterfaceFromType.put("post-collection-update", PostCollectionUpdateEventListener.class);

I think you'd get an error if you used the wrong interface on the wrong event type though and it looks like you have them correct.

mcbi4kh2 · **Joined:** Thu Jun 12, 2008 10:48 am **Posts:** 24

I changed my config to:

Code:

<hibernate-configuration>
  <session-factory>
    <event type="save-update">
       <listener class="mycompany.data.LogListener"/>
    </event>
  </session-factory>
</hibernate-configuration>

But when I break into:

Code:

        EventListeners myListeners = ((SessionFactoryImpl) sessionFactory).getEventListeners();

The value of saveOrUpdateEventListeners in myListeners is "DefaultSaveOrUpdateEventListener".

I presume that value should be "mycompany.data.LogListener"?

Thanks for the help so far

kochcp · **Posted:** Wed Feb 18, 2009 11:05 am

LogListener, if its how it was in the first post, isn't really correct. You'd need to extend the DefaultSaveOrUpdateEventListener, and make sure to call super.onSaveOrUpdate(SaveOrUpdateEvent event) at the end of your implementation otherwise an object would never be actually make it to the saveOrUpdate call.

Code:

MyNewSaveUpdateListener extends DefaultSaveOrUpdateEventListener {

public void onSaveOrUpdate() {

blablabla
blalbalbal
super.onSaveOrUpdate(SaveOrUpdateEvent event);
}
}

and make sure you set it as the "save-update" listener

mcbi4kh2 · **Joined:** Thu Jun 12, 2008 10:48 am **Posts:** 24

yeah that makes sense,

I now have:

Code:

<hibernate-configuration>
  <session-factory>
    <event type="save-update">
       <listener class="myProject.data.LogListener"/>
    </event>
  </session-factory>
</hibernate-configuration>

And my class:

Code:

public class LogListener extends DefaultSaveOrUpdateEventListener

{
  public void onSaveOrUpdate(SaveOrUpdateEvent aEvent) throws HibernateException
  {
    // My code
  }
}

But the saveOrUpdateEventListener is still "DefaultSaveOrUpdateEventListener".

Thanks for the help so far

kochcp · **Posted:** Wed Feb 18, 2009 11:33 am

I don't know how it's not working. You have it in the correct SessionFactory instance? Checking the type correctly? Making sure you're using the one from the context file? I'm just shooting in the dark, it should work how you have it

mmerder · **Posted:** Wed Feb 18, 2009 11:41 am

In spring you have to register your event listeners in a different way. Here is an example I found:

Code:

<beans>
  <bean id="loadListener" class="org.nautsch.MyLoadEventListener" />

  <bean id="myDataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close">
    <property name="driverClassName" value="org.hsqldb.jdbcDriver"/>
    <property name="url" value="jdbc:hsqldb:hsql://localhost:9001"/>
    <property name="username" value="sa"/>
    <property name="password" value=""/>
  </bean>

  <bean id="mySessionFactory" class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">
    <property name="dataSource" ref="myDataSource"/>
    <property name="mappingResources">
      <list>
        <value>product.hbm.xml</value>
      </list>
    </property>
    <property name="hibernateProperties">
      <value>
        hibernate.dialect=org.hibernate.dialect.HSQLDialect
      </value>
    </property>
    <property name="eventListeners">
        <map>
            <entry key="load"><ref local="loadListener" /></entry>
        </map>
    </property>
  </bean>

</beans>

Also look here.

Rating appreciated. ;-)

kochcp · **Posted:** Wed Feb 18, 2009 11:50 am

that's only if you're using the Spring implementation of the SessionFactory. From the looks of it, he is using the Hibernate one in the hibernate.cfg.xml.