Hi!
Dan OConnor wrote:
> The example of multiple distribution protocols is interesting and not
> immediately obvious to me. I think I could make a case that a
> single deployment of an EJB should be able to have multiple
> distribution protocols. The basic argument is that the distribution
> strategy is independent of the business logic (in much the same
> way that a view is independent of a model in MVC).
<snip>
I agree completely. There's just one tiny little catch: if an EJB does
getEJBObject() what should he get? A JRMP EJBObject, or an IIOP
EJBObject, or..? Because of this it is impossible to support multiple
protocols/deployment, hence multiple deployments (one per protocol) is
necessary. :-(
> Let me make the case by example. Say that you have two
> distribution protocols for an entity bean. If our application has
> exclusive access to the database, wouldn't it be reasonable to use
> the same cached entity instance for an access via either protocol?
> This would only be possible if the component had a one-to-many
> relationship with distribution protocols. (Note that this is different
> from the situation where a resource or environment entry is
> different; the EJB container could not reuse a cached instance,
> because it would behave differently based on its corresponding
> deployment parameters.)
Since apps should be accessed by session beans, this isn't that a big a
problem. Use JRMP for EntityBeans to let Sessions access them
"internally", and use multiple sessions with various protocols to access
the app from the outside.
However, you're right in theory. If we only could figure out a way to
implement it consistently I'm all for it.
/Rickard
--
Rickard �berg
Email: [EMAIL PROTECTED]
http://www.telkel.com
http://www.jboss.org
http://www.dreambean.com
