Gene,
I guess it depends on the definition of a "stateful bean".
Per the EJB spec:
* Stateful session beans are not allowed to be accessed from multiple threads.
* Stateless session beans are allowed to be accessed from multiple threads.
* Entity beans (which I would consider stateful) are allowed to be accessed
from multiple threads. To do this correctly requires optimistic concurrency in
the persistence manager.
Whether the EJBObjects used to access these objects are thread safe is up
to the particular vendor. In Borland AppServer (which is built on VisiBroker)
our stubs are always thread safe and multiplexed. Therefore, the request always
gets to the EJB Container intact, even from multiple threads. This is not true
of some other products, where even the stub itself is not thread safe. The EJB
container then makes a determination whether access is allowed; sometimes it
is, and sometimes it isn't, as per the spec. above.
I certainly would not make the blanket statement that EJBObjects are not thread
safe, but maybe that is just a difference in communication style.
-jkw
Gene Chuang wrote:
> EJBObjects are threadsafe in Borland, even for stateful beans???
>
> I know EJBObjects are ALSO threadsafe in Weblogic, but it doesn't make sense
> for 2 threads to hit an stateful EJBObject under ANY container, does it?
> Hence I made the blanket statement that all EJBObjects are not threadsafe...
> I think its just safer for bean developers that way!
>
> Gene Chuang
> Kiko.com
>
> -----Original Message-----
> From: Jonathan K. Weedon [mailto:[EMAIL PROTECTED]]
> Sent: Tuesday, June 26, 2001 1:34 PM
> To: [EMAIL PROTECTED]
> Subject: Re: Thread-safety
>
> Gene,
>
> I am guessing you meant to say:
>
> In WebLogic, EJBHomes are threadsafe, EJBObjects are not.
>
> A different answer is:
>
> In Borland AppServer, EJBHomes are threadsafe, EJBObjects are too.
>
> Unfortunately, I don't believe the EJB spec itself discusses this issue.
>
> -jkw
>
> Gene Chuang wrote:
>
> > EJBHomes are threadsafe, EJBObjects are not.
> >
> > Gene Chuang
> > Kiko.com
> >
> > -----Original Message-----
> > From: Ian McCallion [mailto:[EMAIL PROTECTED]]
> > Sent: Monday, June 25, 2001 5:57 AM
> > To: [EMAIL PROTECTED]
> > Subject: Thread-safety
> >
> > Do the threads of a multithreaded client need synchronise their use of
> home
> > objects and ejbObjects?
> >
> > cheers... Ian
> >
> > ========================================
> > Ian McCallion
> > Alexis Systems Limited
> > Romsey, UK
> > Tel: +44 1794 514883
> > Fax: +44 1794 501692
> > ========================================
> >
> >
> ===========================================================================
> > 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".
>
> ===========================================================================
> 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".
--
Jonathan K. Weedon: Architect
VisiBroker, Borland AppServer
Register now for the 12th Annual Borland Conference: July 21-25 in
Long Beach, California. BorCon is the best place to learn about award
winning technologies for implementing e-business. Register today!
http://www.borland.com/conf2001/
This e-mail, and any attachments thereto, is intended only for use by
the addressee(s) named herein and may contain legally privileged
and/or confidential information. If you are not the intended
recipient of this e-mail, you are hereby notified that any
dissemination, distribution or copying of this e-mail, and any
attachments thereto, is strictly prohibited. If you have received
this e-mail in error, please immediately and permanently delete the
original and any copy of any e-mail and any printout thereof.
===========================================================================
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".
