Dear,

we planned to reengineer all our applications base on a framework using hibernate as persistent manager.

As our migration can not be done in one stage, I was wandering if it iwas possible to migrate the applications part by part, letting hibernate and our internal persistence mechanism working in parallel for a time.

I know that it should have some problem like invalidating hibernate cache or something but does it exist some tips or standard way to let them working toegether for the time of the migration

Thx a lot

Absolutely it is possible! Hibernate is designed to work in applications that do "data access by heterogeneous means".

If you want zero problems, simply disable the second-level cache.

A typical problem will be to include heterogeneous persistence operations within one transaction. You can either to do that via JTA, configuring all involved tools to use transactional JNDI DataSources, or use the Spring Framework's generic transaction support. Spring comes with pre-built support for JDBC, Hibernate, JDO, and iBATIS Database Layer.

Spring also addresses a further typical issue: creating generic DAO interfaces. Besides transaction and resource management support, Spring provides a generic DataAccessException hierarchy, with pre-built conversion support for the above-mentioned persistence strategies.

If you're interested, have a look at the article http://www.hibernate.org/110.html for an introduction to Spring in combination with Hibernate!

Juergen
(Spring Framework developer)