As mentioned in the docs, individual objects and query lists are
cached independently. Of course query lists contain a subset of cached
object store objects inside the lists. An object won't get gc'd if it
is also stored in the query list.
Now list cache expiration is controlled via query cache factory. By
default this is an LRU map, so as long as the map has enough space to
hold lists (its capacity == # of lists, not # of objects), the objects
won't get gc'd.
You can explicitly remove entries from the cache via QueryCache remove
and removeGroup methods. Or you can use a different QueryCacheFactory
that implements some custom expiration/cleanup mechanism.
Andrus
On Nov 11, 2009, at 3:43 PM, Hans Pikkemaat wrote:
Hi,
I use the latest version of cayenne, 3.0b and am experimenting with
the object caching features.
The documentation states that committed objects are purged from the
cache because it uses weak references.
(http://cayenne.apache.org/doc/individual-object-caching.html)
If I however run a query using SQLTemplate which caches the objects
into the dataContext local cache (objectstore),
the objects don't seem to be purged at all. If I simply run the
query dump the contents using an iterator on the resulting
List then the nr of registered objects in the objectstore stays the
same (dataContext.getObjectStore().registeredObjectsCount()).
Even if I manually run System.gc() I don't see any changes (I know
this can be normal as gc() doesn't guarantee anything)
What am I doing wrong? Under which circumstances will cayenne purge
the cache?
tx
Hans
