Business Logic is important - it's often half the app. It is also complicated - Service Layer? Data Access Objects? Enhanced Domain Objects?
We advocate a Transaction Logic engine that plugs into Hibernate events, so user / framework code is not changed (Hibernate APIs are preserved) and re-use / encapsulation is automated. You supply declarative logic (looks somewhat like spreadsheet formulas), and the engine deals with all the dependencies (byte code analysis) / ordering, optimizations etc, reducing 100 lines of code to a single rule… a significant effect on agility and TCO.
Check out www.automatedbusinesslogic.com
