[infinispan-dev] New Cache Entry Notifications

[Mircea Markus]

On Feb 3, 2014, at 4:07 PM, Galder Zamarreño <galder at redhat.com> wrote:

>> 
>> On Jan 23, 2014, at 5:48 PM, William Burns <mudokonman at gmail.com> wrote:
>> 
>>> Hello all,
>>> 
>>> I have been working with notifications and most recently I have come
>>> to look into events generated when a new entry is created.  Now
>>> normally I would just expect a CacheEntryCreatedEvent to be raised.
>>> However we currently raise a CacheEntryModifiedEvent event and then a
>>> CacheEntryCreatedEvent.  I notice that there are comments around the
>>> code saying that tests require both to be fired.
>> 
>> it doesn't sound right to me: modified is different than created.
> 
> I’ve lost count the number of times I’ve raised this up in the dev mailing list :|
> 
> And, if CacheEntryModifiedEvent has a method called isCreated(), is cos I added it in order to differentiate between a modify and a create without breaking backwards compatibility and expectations of events to be received. Just need to trace back the jira issue number, and associated forum threads ;) :p

Sorry for missing this till now :-) If it was raised that frequently through, must be because people are confused about it. As we're having a major release next, I think we should get this right, even if breaking backward compatibility, and document it as such in the migration guide.

> 
>> 
>>> 
>>> I am wondering if anyone has an objection to only raising a
>>> CacheEntryCreatedEvent on a new cache entry being created.  
> 
> It’d break expectations of existing applications that expect certain events. It’s a very difficult one to swallow.

we're at a major now, so we should break compatibility if it makes sense.

> 
> Plus, there’s JCache specifications, which adds listeners, and gets them right. Eventually everyone should move towards that.

Not sure I understand: JCache raises both an "created" and a "modified" event when an entry is created? or just "created" events? 

Cheers,
-- 
Mircea Markus
Infinispan lead (www.infinispan.org)