I currently have our application running using OJB. I am using the PB interface because it was the easiest to prototype and get up and running.
We have a Struts application that calls a collection of EJB services for retrieving specific object-trees that the web app needs, along with Add/Update/Delete methods on the EJB's. One of my main selling points for convincing the team to move away from PHP to Java/J2EE was the strengths of O/R tools like OJB, specifically the cache -- I think it is a strong seller, especially in a 80% read-only application. So, to facilitate that, I constructed a Façade wrapper around the PersistenceBroker (so, if I wanted to, I could swap it to ODMG/JDO), and it seems to work well. I have deployed our 'Core' application as a collection of EJB's that make use of OJB under the hood, and then our web application as separate war file. But, because they are in the same container (Jboss), it makes use of the Local versus Remote interfaces -- which is desired. However, when using the cache, and the local interface, any manipulation done by the web application on it's objects is manipulating the object in cache. I always though of the cache as a 'clean' representation of what was in the database -- so in all of my retrieve methods in my EJB's, I return clone's of the DataObjects. This allows for the client applications to manipulate them, and not affect the cache objects, and send them for committing, also updating the cache. But because PB API is not a full persistence API, I am starting to hit the issues that API's like ODMB fix (deleted objects in collections, object locking, etc) -- and want to get a feel for how best to use something like ODMG in my situation. My goals are: 1) To have a centralized application that handles all database and service level transactions. It would hand out objects from the cache (preferably clones) and receive objects to store them. We only have one client application that would be using this, but down the road we will have many more 2) Move to an ODMG like API that can manage locking and whatnot to free up not having to manage object locking, deletion, etc 3) For Goal 1 to make use of the cache -- most of our applications are read-only. So that makes sense to make heavy use of the cache -- but at the same time we do have update scenarios that I would like to be 'atomic'. Is there a pattern that facilitates these goals? Thanks! -Andrew --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
