Consider two tables

Customer and Items;

On the Customer entity I enabled second level cache for getItems();

Can any one please confirm when will the cached set of Items for Customer be removed from the cache.

(1) When a new Item is added or ant existing Item is updated.
(2) When a new Item is added and the new Item is also associated to Customer, or an existing Item that is associated to Customer is updated.

Please let me know which one of the above will invalidate the cache.





I would prefer the option (2).

As I want the Customer.getItems() to be in cache and I do not care if a Items table is updated with a new Item that is not associated to Customer, my cache should not be effected.

If I want to achive the above use case what do I need to do?

Thanks,
Naseer.

http://www.javalobby.org/java/forums/t19807.html

and

http://forum.springframework.org/showthread.php?t=29691

HTH

I still did not get the answer to my question,

I am looking for a way to invalidate second level cache only if there is the contents cached are changed, not if the referring table is updated.

AFAIK, collection caches are removed if a cache setting for that region forces so or a cluster invalidation message is received by your cache. As in your case I believe you are fine. Hibernate does not actually cache object instances in a collection, and it only caches the keys to objects in an association. Therefore, if a new item is added to the system it has nothing to do with your collection cache. However, if an Item that is already in an association is updated you will get the updated Item object the next time you fetch the object from cache. To make things clear, imagine this example: You have three items in your cache:

[1]=[Soap]
[2]=[Bread]
[5]=[Milk]

and your customer is:

[1]=['Someone', 'Somewhere', [2,5]]

In this example [2,5] is the relation between items and the customer keyed 1.


Does this answer your question?