Sven,
> -----Original Message-----
> From: Sven-Uwe Meyer [SMTP:[EMAIL PROTECTED]]
> Sent: Wednesday, March 03, 1999 7:52 PM
> To: [EMAIL PROTECTED]
> Subject: Re: IDL from EJB
>
> thanks Chris,
>
> just to be sure I understud everything fully (before spending many hours
> coding):
>
> - EJB-server applications will always be writting EJB(RMI)-style / the
> code-generators of the container/server on which the EJB will be
> deployed will generate RMI- or CORBA-proxys-classes (when CORBA is
> supported)
>
Bingo!
> - when using CORBA on the server-side i have to write my client using
> CORBA as well or can write my code RMI-style and can use (in the near
> future) RMI-over-IIOP
>
You have to write the client using CORBA, or can use RMI over IIOP (if your
vendors support it).
> any problems with OBV or IIOP-firewall-proxies ?
>
Well, I am not sure where the industry is with OBV. We passed on it with
the current release because the spec was still drying as we were releasing.
As far as IIOP, some vendors support http tunnelling, and assignment of
specific ports for allowing other protocols. We do the latter for now. For
customers focused on Internet deployments, they tend to shy away from
iiop over the net in favor of servlets...
> thanks, sven
>
>
> Chris Raber wrote:
> >
> > I'll take a stab at your questions.
> >
> > > -----Original Message-----
> > > From: Sven-Uwe Meyer [SMTP:[EMAIL PROTECTED]]
> > > Sent: Wednesday, March 03, 1999 7:50 AM
> > > To: [EMAIL PROTECTED]
> > > Subject: Re: IDL from EJB
> > >
> > > Chris Raber wrote:
> > > >
> > > > The EJB CORBA mapping specification describes how this should work.
> > > >
> > > > It is a question of whether a particular vendor supports it or not.
> > > > GemStone/J
> > > > for example is built on top of CORBA, so we will be able to support
> this
> > > > eventually. We are not quite there yet. In the interim you can
> create a
> > > > CORBA
> > > > object and expose it's IDL to CORBA client, and have the
> implementation
> > > > of that CORBA object simply turn around and invoke on EJB's.
> > >
> > > I'm in the phase of having to decide if i use RMI or CORBA for my
> > > proof-of-concept-prototype (based on Gemstone/J 2.01) and I'm not
> quite
> > > sure if i understand the topic (and problems) fully.
> > >
> > > - Is this really or problem ? Do i really have to decide now to use
> RMI
> > > or CORBA now.
> > >
> > As an EJB developer the transport level is transparent. The semantics
> are
> > like
> > RMI, but the underlying mechanism might actually be CORBA/IIOP. This is
> how
> > GemStone/J is archictected.
> >
> > > - would it make sense to use RMI now (easier ?) aand "upgrade" to
> CORBA
> > > later ?
> > >
> > >From a developers standpoint, it makes no difference. The CORBA
> > infrastructure
> > provides a richer backbone for EJB assuming a CosTransaction services is
> > there.
> >
> > > - could I write my clients using RMI and use RMI over IIOP later so
> that
> > > i don't have to change my code to use CORBA ?
> > >
> > You could do this, but you won't have to change code wither way. One
> defines
> > home and remote interfaces and bean implementations to the EJB standard
> and
> > an EJB server gives them life in the context of RMI or CORBA/IIOP. The
> > semantics
> > of the object distribution to the developer are always RMI'ish.
> >
> > > - ... or would it be possible (with not too much overhead) to put all
> > > RMI/CORBA-specific code in some extra layer/classes so that i only
> have
> > > to replace them later ?
> > >
> > The only CORBA specific code would be if you have non-EJB clients which
> are
> > CORBA based, talking to EJBs.
> >
> > > - is (will) there a (automatic) way to use CORBA instead of RMI later
> > > (just redeploying on a CORBA-capable EJB-server/container) ?
> > >
> > Yes. This is true today!
> >
> > > thanks to anybody who takes some time to clarify this topic,
> > >
> > At your service.
> >
> > > sven
> > > --
> > >
> -----------------------------------------------------------------------
> > > Sven-Uwe Meyer
> > > Gruner+Jahr Electronic Media Service GmbH tel. : +49-40-370 377
> 29
> > > Am Baumwall 11 fax. : +49-40-370 377
> 57
> > > 20459 Hamburg
> > > Germany email :
> [EMAIL PROTECTED]
> > >
> -----------------------------------------------------------------------
> > >
> > >
> ==========================================================================
> > > =
> > > To unsubscribe, send email to [EMAIL PROTECTED] and include in the
> > > body
> > > of the message "signoff EJB-INTEREST". For general help, send email
> to
> > > [EMAIL PROTECTED] and include in the body of the message "help".
> >
> >
> ==========================================================================
> =
> > To unsubscribe, send email to [EMAIL PROTECTED] and include in the
> body
> > of the message "signoff EJB-INTEREST". For general help, send email to
> > [EMAIL PROTECTED] and include in the body of the message "help".
>
> --
> -----------------------------------------------------------------------
> Sven-Uwe Meyer
> Gruner+Jahr Electronic Media Service GmbH tel. : +49-40-370 377 29
> Am Baumwall 11 fax. : +49-40-370 377 57
> 20459 Hamburg
> Germany email : [EMAIL PROTECTED]
> -----------------------------------------------------------------------
>
> ==========================================================================
> =
> To unsubscribe, send email to [EMAIL PROTECTED] and include in the
> body
> of the message "signoff EJB-INTEREST". For general help, send email to
> [EMAIL PROTECTED] and include in the body of the message "help".
===========================================================================
To unsubscribe, send email to [EMAIL PROTECTED] and include in the body
of the message "signoff EJB-INTEREST". For general help, send email to
[EMAIL PROTECTED] and include in the body of the message "help".
