On Jan 8, 2007, at 3:48 PM, Dain Sundstrom wrote:
On Jan 8, 2007, at 11:59 AM, Andrus Adamchik wrote:On Jan 8, 2007, at 9:39 PM, Dain Sundstrom wrote:Well, we depend on being able to listen to events on the EM which there is no spec interface for. I'm sure Cayanne has and interface that can provide us with the events, and when they send us the info we can add a hook for their Impl.What kind of events?We need afterLoad, beforeStore, afterAttach, beforeDelete, and afterDetach so we can make the proper EJB Entity bean callbacks. The code we use for OpenJPA is here:http://svn.apache.org/viewvc/incubator/openejb/trunk/openejb3/ container/openejb-core/src/main/java/org/apache/openejb/core/cmp/ jpa/JpaCmpEngine.java?revision=492404&view=markup&pathrev=492419look for OpenJPALifecycleListener inner class. -dain
Dain, I just checked in the code to register Cayenne callback listeners. 1. The API description...https://svn.apache.org/repos/asf/cayenne/main/trunk/framework/cayenne- jdk1.4-unpublished/src/main/java/org/apache/cayenne/ LifecycleListener.java
class CayenneListener implements org.apache.cayenne.LifecycleListener {
...
}
EntityManager em = ...;
CayenneEntityManager cem = (CayenneEntityManager) em;
LifecycleCallbackRegistry registry = cem.getChannel
().getEntityResolver().getCallbackRegistry();
registry.addDefaultListener(new CayenneListener());Note that callback registry is shared by all EntityManagers obtained via a given EntityManagerFactory, so listener registration is needed only once per EMF life-span.
2. The callback types... The callbacks that Cayenne currently provides are all following the JPA spec. Mapping them to the callbacks that you mentioned we get this:
afterLoad -> postLoad beforeStore -> prePersist,preUpdate beforeDelete -> preRemove afterDetach -> afterAttach ->There is no attach/detach callback. Does it make it a show stopper for testing with OpenEJB? Or rather, does it make sense to code a workaround on the OpenEJB end, making it more portable in only relying on standard JPA callbacks (not sure whether it is possible)? Or otherwise we can do it in Cayenne.
Andrus
