ConversionManager - Override and Class Loader Issues

Question

Hi
We are using Toplink 10.1.3 deployed withiin 10gAS 10.1.3.
We have overridden the ConversionManger as documented in tips.
1. MyConversionManager extends ConversionManager.
2. We have overriden convertObject
3. We have a pre-login SessionEventAdapter that sets the ConversionManager.
We have had issues of classloading within the application previously, particularly where we have two versions of our application deployed on the same App Server instance (potentially with differing versions of MyConversionManager).
For this reason we only set the ConversionManager within the preLogin event on the Session as follows:
*//Just set the conversion manager for the session.*
event.getSession().getLogin().getPlatform().setConversionManager(getConversionManager());
We no longer set the default conversion manager, as my understanding was that this would set it at the root level within the OC4J instance (meaning that each deployment would override the previous).
Additionally, we have had to sepcify the class loader to use, within the ovverriden convertObject method, as otherwise start up of Toplink falied, as it was unable to solve references to application classes specified within class indicator mappings. We do this as follows:
*@Override*
*public Object convertObject(final Object source, final Class javaClass) {*
super.setShouldUseClassLoaderFromCurrentThread(true);
The only know issue with this, is that if I try and use OEM to veiw the Toplink Cache, I just get and AnnotatedClassNotFoundException as it is attempting to use the system class loader (that does not contain our Application classes).
Two questions therefore:
1. Is the deployment we have now stable, i.e. overriding the class loader within the overriden Conversion Manager, and only loading this against the session??
2. How can I get mutiple versions of the application to still work, together with being able to view the Toplink Cache from within OE:M.
Any help or insight, would be greatly appreciated.
Marc

Answer 1

Looks fine, you may also wish to investigate using Converters in your mappings instead of customizing the ConversionManager.
For the OEM issue, try setting the class loader to be your application class loader instead of the thread one, i.e. MyAppClass.getLoader().
James : http://www.eclipselink.org