Hey
"Ferguson, Jon" wrote:
> I've just run into a modelling wall - or just have a naive understanding
> of Weblogic's implementation of CMP. Perhaps you can help.
>
> Assume I need to model a car as a course grained component. Since a car
> is rather complex I use aggregation to connect up all its parts. Then I
> say things like 'start' and 'stop'. Assuming I'm using a relational
> database, my first instinct is that the car will have a data model using
> several tables, possibly with joins. It appears that using Weblogic and
> CMP I can only model simple: attribute=field type relationships from a
> record of a single table. Thus it seems like I therefore must model
> each simple component as a separate entity bean and then wrap the sum in
> a 'car' session bean.
>
> If this is the only way to do this using CMP and Weblogic then I can
> suffer it - but I don't like. Firstly, because this forces me to
> aggregate at a much finer level than the object-model requires, and
> therefore, opens up a much wider interface to abuse. Secondly, I
> instinctively think of communications between beans as being less
> efficient than standard object-to-object communications.
>
> I've used other EJB servers which do cope with more complex senarios so
> am I missing something?
A, perhaps terrible, idea:
make the database table consist of a LONGCHAR (+ pk fields) and convert
your Car-data into an XML-string that you persist. Works with rather
complex aggregated objects but may be inefficient.
Using an OODBMS or some O-R mapping tool is probably preferred.
/Rickard
--
Rickard �berg
Computer Science student@LiTH
@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".
