I'm using Hibernate Annotations 3.1beta8 and I'm trying to implement optimistic locking on an existing table. To enforce version numbering the version number field is automatically updated by a database trigger, and that trigger throws an error if the application tries to update the version number.

If I mark the field as versioned
then hibernate tries to set the field on every update causing the update to fail. If I set the field as not updatable then hibernate doesn't do optimistic locking. Adding '@GeneratedValue' to it doesn't change anything.

Is there anyway to tell hibernate to do optimistic locking but not try to update the version number itself? Also more generally is there anyway to tell Hibernate the column is updated by the database on every update, not just on insert?

I'm not sure if this is doable, maybe by implementing a usertype (VersionType)

There is a generated=true on hbm files but there is no equivalent in annotations so far

I've managed to find a work around that didn't require using the xml config files but instead used a new annotation to indicate what properties should be loaded dynamically.

First I add all the classes to the AnnotationConfiguration as usual. After that I call buildMappings to ensure all the mappings are created and all the hibernate annotations applied. Then I go back over all entity classes looking for my new annotation. If I find it I use getClassMapping and then getProperty to get the property for the annotated element and then use the setGeneration method on Property to set the generation time to PropertyGeneration.ALWAYS. After I've done that hibernate handles the optimistic locking the way I need it to.

That a possibility but it would be much easier, faster at runtime to patch AnnotationBinder itself