On Mar 10, 2007, at 2:15 AM, Aristedes Maniatis wrote:
On 10/03/2007, at 10:13 AM, Tore Halset wrote:
Hello.
I am a lifecycle callbacks newbie trying to understand http://
cwiki.apache.org/CAYDOC/lifecycle-callbacks.html in a ROP context.
Can the callback methods be defined in the client PersistentObject
or only in the server CayenneDataObject?
I believe that they will only operate on the server side. At least
that's how we've been able to use them.
True. Let's put it this way - no decision has been made on the client
callbacks yet.
Can a ROP client perform non-lifecycle callbacks on the server? If
not, are there any other standard way for a ROP client to call a
method on the server not related to the persistence lifecycle?
We use Jetty as the transport for Hessian between client/server
ROP. So we can define special servlet calls as we need in order to
perform code on the server or return values. For instance, when a
client logs into the server we wanted the server to maintain a list
of client sessions. So, because we aren't committing an object
through Cayenne to the server we couldn't use a lifecycle event and
we wrote a special servlet call which is used instead.
IIRC, Tore mentioned this before, that it would be nice to define
some arbitrary RPC-like calls to the server-side peer objects, kind
of like EOF does. So that you can do clientObject.doX() and it will
proxy the call to the serverObject.doX(). I'd say this can be a new
feature in 3.0, and it would be nice if somebody volunteers to do it.
Andrus
