Christopher Cobb wrote:
>
> So if these nice app servers are doing all this work for us, to what extent should
>the typical applications developer be concerned with issues of multiplicity of
>objects. And what general design patterns should we follow to keep our multiplicity
>low?
The main pattern is this respect is "don't use a stateful session bean
where a stateless session bean would suffice".
> cc
>
> Dave Wolf wrote:
>
> > Sybase EAServer is also similar. We create no EJBObject instance. We do
> > have some internal objects as part of our dispatcher code, but they are not
> > exact analogs of the EJBObject. To use the EJBObject is simply a logical
> > idea.
> >
> > Our product is more TIE based so we do have a skeleton but again not an
> > EJBObject.
> >
> > Dave Wolf
> > Internet Applications Division
> > Sybase
> >
> > ----- Original Message -----
> > From: "Jonathan Weedon" <[EMAIL PROTECTED]>
> > To: <[EMAIL PROTECTED]>
> > Sent: Monday, November 27, 2000 5:37 PM
> > Subject: Re: EJB Object implementation
> >
> > > Rickard,
> > >
> > > I am so excited: we agree!
> > >
> > > <vendor>
> > >
> > > I very much agree with Rickard that creating anything in the server to
> > > represent each object is a waste of resources. Likewise, our product
> > > avoids doing so, and thereby avoids the associated memory overhead.
> > >
> > > I am curious what other vendors have this capability, if any. That is,
> > > what is the incremental cost of instantiating a new object over the long
> > > run? For example, if there are N Stateful Session Beans in the
> > application,
> > > is there a O(N) memory requirement? In our server (and JBoss) there is
> > > not, only a O(N) disk space requirement (which is needed to store the
> > > passivated beans). If the memory required is linear with the number of
> > > objects, obviously the server cannot truly scale.
> > >
> > > Unfortunately, you can't read our source code to see how this is done.
> > > But you can read the OMG's Portable Object Adapter specification, which
> > > outlines the server-side dispatch-model of our CORBA product, on which
> > > our AppServer is built.
> > >
> > > </vendor>
> > >
> > > -jkw
> > >
> > > Rickard �berg wrote:
> > > >
> > > > On Mon, 27 Nov 2000 09:55:33 +0500, [EMAIL PROTECTED]
> > > > wrote:
> > > > >**In short when u call create() on home interface the container creates
> > > > >a EJBObject and associates it with a class instance from the pool.(the
> > > > >primary key is the binding factor between the two.)
> > > >
> > > > <vendor>
> > > > Note that when you say "create an EJBObject" that does not necessarily
> > > > mean that a physical object is created on the server. That is *one*
> > > > implementation option, and in the case of JBoss we have chosen *not* to
> > > > create such objects since it affects scalability negatively.
> > > >
> > > > For example, you can have a finder method return an enumeration of
> > > > 1.000.000 EJBObjects. This does *not* mean that there are now 1.000.000
> > > > objects being created on the server, since that would be a serious
> > > > resource drain.
> > > >
> > > > For more information I suggest you simply read the source code for our
> > > > server. It's all there. See www.jboss.org for details on source
> > > > download.
> > > > </vendor>
> > > >
> > > > /Rickard
> > > >
> > > > --
> > > > Rickard �berg
> > > >
> > > > Email: [EMAIL PROTECTED]
> > > > http://www.telkel.com
> > > > http://www.jboss.org
> > > > http://www.dreambean.com
> > > >
> > > >
> > ===========================================================================
> > > > 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".
--
________________________________________________________________________________
Evan Ireland Sybase EAServer Engineering [EMAIL PROTECTED]
Wellington, New Zealand +64 4 934-5856
===========================================================================
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".
