Question

We are setting up a Jboss cluster and we are building an own distributed cache solution built upon Jboss cache (Cant use it as 2nd level cache to ORM layer in our case). We want to use invalidation and not replication as cache mode. As far as i can see after (very) little testing both solutions seem to work, objects are put into the cache and objects seem to be evicted when they are updated on any of the servers.
This leads me to believe that PojoCache with AOP instrumentation is only needed when using replication so that you can replicate only updated field values and not whole objects. Am I correct here or are there any other advantages with using PojoCache over TreeCache in our scenario? And if PojoCache have advantages, do we still need AOP instrumentation and to annotate our entities with @PojoCacheable (yes, we are using JBCache 1.4.1) since we are not using relication?

Regards
Jonas Heineson

Answer 1

PoJoCache has the ability through AOP to:

• only replicate changed fields and not whole objects. Makes a difference if e.g. your person object containes a huge image of the person and you only change the password
• detect changes and thus can automatically put them on the list to be replicated.

TreeCache (plain) does not need AOP, but can thus not replicate individual fields or detect what has changed so that you need to trigger replication yourself.

If you don’t replicate, those points are probably irrelevant.

IIrc, you don’t need the @PojocaCacheable annotation for Pojo cache – without it, you need to specify the classes to be enhanced in a different way.

I have the feeling that if you are not replicating, the plain TreeCache will be enough.