What is a IncompatibleClassChangeError exception in Java?

Question

i am working on a small application and I am trying to use Hibernate Annotations to map my entities. I wanted to test if everything is alright when i got this exception :

Answer 1

JDK 1.4 support has been dropped in 3.6. So Hibernate Annotations has been merged back into Core and there is no more need to have both Configuration and AnnotationConfiguration and the later should not be used in 3.6.x (actually, you should probably use the JPA EntityManager, not the core API, but this is another story).

But my real advice would be to use the 3.5.x branch of Hibernate, not the 3.6.x. As we already saw, the Hibernate team is introducing big changes in 3.6, which is on top of that still in Beta, and unless you are following the changes closely, you'll face some surprises and won't find many resources on the internet yet. Just use Hibernate 3.5 (3.5.5-Final at the time of writing this).