Querying TopLink Cache

Question

My system demands caching the result sets obtained from a ReadAllQuery. I might make several queries on this static set of cached data. But the data to be cached is small. I use TopLink's use session.getProject().FullIdentityMap() to cache the output of ReadAllQuery that i execute at the start of the system.
But am not able to query the cache from an external API later ( which could be several minutes later). How can i manipulate the TopLink cache APIs to get this done. Kindly Reply.

Answer 1

Hi Manoj,
If I understand you correctly, you persist some objects and then later query them. You don't get the results you expect when you use checkCacheOnly(). You need to use checkCacheThenDatabase() and when you do this you're seeing SQL I expect.
If your cache type for the class is FullIdentityMap then TopLink will never release objects of that class once read and your checkCacheOnly() query should work.
I'm guessing that you're using a different TopLink session. You mention you have a number of services. What environment are you running in and what is your architecture (e.g., servlet or EJB)? Statics don't solve sharing problems especially in an application server or web application environment in which multiple classloaders are employed.
--Shaun