cayenne-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Francesco Romano <francesco.rom...@abodata.com>
Subject Re: Cayenne shared cache invalidation
Date Wed, 22 Aug 2012 13:24:48 GMT
:)
Thank you very much

Francesco

On Aug 22, 2012, at 3:20 PM, Andrus Adamchik wrote:

>> Is this acceptable (at least .. waiting for our update to cayenne) ?
> 
> Yep. See my other message. We both guessed the cause of the issue simultaneously :)
> 
> Andrus
> 
> 
> 
> On Aug 22, 2012, at 4:12 PM, Francesco Romano wrote:
> 
>> On Aug 22, 2012, at 3:04 PM, Andrus Adamchik wrote:
>> 
>>>> Local cache is local to a data context (right?). But currently the application
creates a new datacontext for every "transaction", so if I understood correctly the local
cache is useless and I should use the shared cache.
>>> 
>>> Correct.
>>> 
>>>> I also tried to add a listener (on postPersist, postUpdate and postRemove)
to clear the cache for that particular group, but it does not work:
>>>> 
>>>> private void clearCache(Object entity) {
>>>> 	Persistent object = (Persistent)entity;
>>>> 	QueryCache cache = ((BaseContext)object.getObjectContext()).getQueryCache();
>>>> 	cache.removeGroup(object.getClass().getName());
>>>> }
>>> 
>>> This is going in the right direction. So is listener method invoked, but the
cache is not cleared, or the listener method is never invoked. 
>>> 
>>> BTW Cayenne 3.1 has a nice set of extensions called cayenne-lifecycle. The docs
are still sparse (we are working on those), but there is a @CacheGroups annotation placed
on persistent classes that tells Cayenne that any changes to a given type of objects should
generate a cache invalidation event. E.g.:
>>> 
>>> @CacheGroups("news")
>>> public class News extends com.foo.auto._News { }
>>> 
>>> processing of this annotation is enabled by installing org.apache.cayenne.lifecycle.cache.CacheInvalidationFilter
(also part of cayenne-lifecycle):
>>> 
>>> DataChannelFilter filter = new CacheInvalidationFilter();
>>> 
>>> CayenneRuntime runtime = ...
>>> 
>>> // a bit clunky.. may merge the following 2 lines in one in the future releases:
>>> runtime.getDataDomain().addFilter(filter);
>>> runtime.getDataDomain().getEntityResolver().getCallbackRegistry().addListener(filter);
>>> 
>>> Cheers,
>>> Andrus
>>> 
>> 
>> Thank you for your answer.
>> I don't think we can update our cayenne right now, but we will take a look at the
annotations asap (it means: when we can spend some time to update cayenne).
>> 
>> This morning I think I found a solution which seems to work:
>> 
>> private void clearCache(Object entity) {
>> 		Persistent object = (Persistent)entity;
>> 		ObjectContext context = object.getObjectContext();
>> 		if (context instanceof DataContext) {
>> 			DataContext dataContext = (DataContext)context;
>> 			QueryCache cache = dataContext.getParentDataDomain().getQueryCache();
>> 			cache.removeGroup(object.getClass().getName());
>> 		}
>> 	}
>> 
>> Is this acceptable (at least .. waiting for our update to cayenne) ?
>> 
>> Regards
>> Francesco Romano
>> 
>>> 
>>> On Aug 21, 2012, at 6:36 PM, Francesco Romano wrote:
>>>> Hi everybody.
>>>> 
>>>> I'm trying to add caching support (query cache) to a project which uses cayenne.
>>>> For what I understood in the online documentation there are two types of
caches: local and shared.
>>>> Local cache is local to a data context (right?). But currently the application
creates a new datacontext for every "transaction", so if I understood correctly the local
cache is useless and I should use the shared cache.
>>>> 
>>>> Now... the problem.. I have a query cached (a sort of select * from table)
and a new row is added in the table. I would like that the next time the same query is called
also the new row is fetched.
>>>> 
>>>> This is the query cache
>>>> 
>>>> SelectQuery select = new SelectQuery(t);
>>>> Class t; //this is the class of the persistent object to be fetched		
>>>> select.setCacheStrategy(QueryCacheStrategy.SHARED_CACHE);
>>>> 		
>>>> select.setCacheGroups(t.getName());
>>>> 
>>>> This is my "sample" test code (Network is a Cayenne Object class) (GetAllNetwork
is a selectquery with the above caching. AddNetwork adds a new object and commit it. A new
DataContext is used every time)
>>>> 
>>>> List<Network> networks = dbHandle.GetAllNetwork();
>>>> Network net = dbHandle.AddNetwork();
>>>> List<Network> newNetworks = dbHandle.GetAllNetwork();
>>>> 
>>>> assertEquals(networks.size() + 1, newNetworks.size());
>>>> 
>>>> 
>>>> Now... my assert is not true, because the query is cached.
>>>> I also tried to add a listener (on postPersist, postUpdate and postRemove)
to clear the cache for that particular group, but it does not work:
>>>> 
>>>> private void clearCache(Object entity) {
>>>> 	Persistent object = (Persistent)entity;
>>>> 	QueryCache cache = ((BaseContext)object.getObjectContext()).getQueryCache();
>>>> 	cache.removeGroup(object.getClass().getName());
>>>> }
>>>> 
>>>> Any help?
>>>> 
>>>> Thanks
>>>> Regards
>>>> 
>>>> Francesco Romano
>>>> 
>>> 
>>> 
>> 
> 
> 


Mime
View raw message