Paz Offer writes:
> Thanks Phil,
> Very helpfull information indeed!
> Please bare with a couple of more questions (if I may) it would realy help
> me (please,please):
>
> Regarding the Activation issue:
> Is the OAF is a fully CORBA compliant feature?
>
No, activation is unspecified in corba. The OAF apis are proprietary.
What is 'sort-of' specified is how an implementation repository should
work.
Basically
1) The Object IOR of a 'persistent' (i.e. long-lived) object contains
the destination of the 'implementation repository' (IMR) service in it
2) The client makes a call on a method of the object pointed to by the
IOR
3) The IMR gets the call, creates the object (and could conceiveably
negotiate with the orb behind the scenes to load a dll if required),
and then forwards the request.
> I done some reading about CORBA, and nowhere did I find (yet) any mention
> regarding activation - in the sence that (MS) COM does it:
> a. COM server is registered with the system registry..
> b. COM runtime will - find the dll, activate the object and
> download the dll when all is done..
Yep - COM specifies activation (albeit a bit crappily - requiring a
'registry'). CORBA doesn't. Clients assume that objects are long
lived. For similar functionality, people tend to do the following:
1) write a long-lived 'factory' object, who creates the objects. (like
com factories or EJB Homes)
2) register the factory with a corba naming service
3) use some 'magic' to load the factory when people attempt to use
it. (either by the implementation repository scheme described above,
or by a naming service which automatically instanciates factory
objects on demand - this is what gnome does)
I intend on writing an IMR based on OAF (if it's a good fit) in the
medium term. Don't rely on this though (unless you want to help ;-)
It might be worth looking at the gnome nameserver stuff to see if this
fits your needs.
Cheers,
Phil
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