I think we can view EJB over RMI as distributed system over a network system. In
a network system, you need to know the machine name in order to get something
from it. However, in a distributed system, you can assume that everything is
floating. If what you need appears in multiple machines, the system will select
one for you, load-balanced. This way, the system is more reliable, and more
scalable. Because commercial distributed OS is not in the market yet, we are
trying to achieve the distributing goal in application level. The EJB
architecture fits into this category. When we want to gain something, we must
pay a price. Those restrictions is the price. You may thing that this price is
too expensive now. But it will reduce when this architecture becomes clever.
Lam
Ron Yust wrote:
> Rickard,
>
> The only wall I'm smashing my head against is EJB and the inability to get
> consistent straight answers. I'm trying to design a solution for our needs
> and not around EJB. I have a factory pattern application that currently
> runs fine with RMI. In essence, the design mimics session beans getting
> JDBC connections and doing their own transaction management. I want to give
> ourselves and customers of our system the option of running the server under
> RMI native or in a EJB container. Simple as that. Flexibility and customer
> choice -- not to force a technology down their throats if they don't need
> it.
>
> So, my architecture is in place and all I'm trying to understand is where
> EJB will jump in and tell me NO YOU CAN'T DO THAT. A lot of the EJB spec
> seems vague. Everyone on this listserv appears to interpret the spec in
> different ways with sometimes conflicting answers.
>
> So far from what I've seen, unless I want to use entity beans, an existing
> RMI server is similar to an EJB server (albeit with less capability) and
> running the application under both environments appears feasible.
>
> Please don't respond to my inquiries if it is a bother. I'm here to learn
> and my probing may help other novices perusing our messages.
>
> -Ron
>
> > -----Original Message-----
> > From: A mailing list for Enterprise JavaBeans development
> > [mailto:[EMAIL PROTECTED]]On Behalf Of Rickard �berg
> > Sent: Wednesday, October 27, 1999 5:04 PM
> > To: [EMAIL PROTECTED]
> > Subject: Re: EJB Restrictions-- threads, io
> >
> >
> > Ron Yust wrote:
> > > Please be patient with my ignorance. If I have no entity beans, and my
> > > session bean is handling transaction management via JDBC, would tx
> > > management still fail?
> >
> > You can't "handle transaction management via JDBC". That is done through
> > the Transaction Coordinator, which you as a session bean cannot access.
> > If you're referring to simply calling begin, commit and rollback on JDBC
> > connections, that is not tx management.
> >
> > Do this:
> > * Acquire connections by looking up the appropriate DataSource through
> > JNDI
> > * Do queries against the database using the connections
> > * Release the connections when you're done with them by calling close()
> > * Do nothing more than the above steps. The app server will take care of
> > everything else. That's its job.
> >
> > Why do you want to smash your head against the wall and insist on doing
> > it the wrong way? I don't get it...go with the flow dude...
> >
> > /Rickard
> >
> > --
> > Rickard �berg
> >
> > @home: +46 13 177937
> > Email: [EMAIL PROTECTED]
> > Homepage: http://www-und.ida.liu.se/~ricob684
> >
> > ==================================================================
> > =========
> > 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".
