We are finalizing on our persistance strategry for a J2EE project based on Websphere 6.0 platform. Websphere portal 5.1 will be used as the persentation tier. We are inclined to use hibernate 3.0.5 for as the persitnace framework for the project. If somebody has used this combination for any of their recent projects and can share their experience it will be helpful. Some of the concerns which i have are expecially with respect to

transaction managment
2nd level cache.

My application will be running in a WAS clustered environment. (30 app servers, 10 portal server)

Which is the best cache implementation that i can use for this kind of an application ?
Is there some pointers on the best practices in caching strategies ?
How do these cache implementations keep themselves synchronized ?

Any help would be great.

Regards
- rgopalak

I have only used Hibernate with JBoss, so I don't know if there is an easy way to get a Hibernate Session onto the current Thread with Websphere. For JBoss, there is an EJB interceptor which does that. Lacking that, you might have to put some code into every EJB method to open and close the Session.

Transaction Management: You definitely want to integrate with JTA to handle your transactions. Fortunately, you just have to configure hibernate.properties accordingly. Take a look at the section named Transaction API, it is well-documented.

2nd Level Cache: Strongly recommended in an EJB environment. Keeping a Session open between remote calls is bothersome and even unwanted if you are using detached objects; then the 2nd level cache becomes the only cache. You should use JBossCache since it is the only transactional cache, all others might leave invalid data in the cache if a transaction rolls back.

Addendum: JBossCache can be configured to replicate itself, you might want to use this for your cluster. Just to be safe, you should version or timestamp your data (those are Hibernate column types) to ensure that you don't get conflicting updates.

Hi,

I have worked with hibernate on WLS 6.1 and WLS 8.1

I suggest you to use session-per-request anti pattern for managing transaction.

As per as caching is concerned, I may consider OSCache or Swarmcache. I have worked only with OSCache. With OSCache, the clustering is supported via JavaGroups or JMS.