"evict" safety

rong · **Joined:** Thu Mar 25, 2004 2:32 pm **Posts:** 6

Hi all,

I am thinking about using hibernate's second level cache with database change notification. Basically if some legacy application updates the database from underneath me, I want to either through a database trigger or through polling get notified about the change, then evict the affected objects from the second level cache. Essentially what this article talks about:

http://www.theserverside.com/articles/a ... rs-Writers

So I am wondering if hibernate's "evict" operations are safe enough without using the locks? Can my background thread do the evictions while the business tier still access the cache at the same time?

Thanks,

Rong

emmanuel · **Posted:** Wed Jan 12, 2005 7:23 am

From the API

Quote:

Evict an entry from the second-level cache. This method occurs outside of any transaction; it performs an immediate "hard" remove, so does not respect any transaction isolation semantics of the usage strategy. Use with care.

rong · **Joined:** Thu Mar 25, 2004 2:32 pm **Posts:** 6

Yes, I've read the javadoc. It's just not completely clear to me what it means. My guess is to be safe I'd have to do the reader/writer lock for background eviction.