I've been working with AOP since AspectJ (http://www.aspectj.org) was in its
0.6 release; I used to think the way you do, but I'm slowly beginning to see
that doing so misses something of the point in AOP.
Containers are a component-oriented principle: we create binary independent
units of distribution and deployment (see Charles Szyperski's "Component
Software") and push them into a container, which can then in turn provide
services to the component, usually through some kind of an interception
model. EJB, COM+ both follow this model.
AOP, however, is really much much more than just an interception
technology--it allows us to do away with the container completely. Because
aspects are woven in at compile-time, there is no need for interceptors to
provide the services desired. Because there is no need for interceptors,
there is no need for the container as a whole. We go back to writing
standalone apps.
Certainly, we lose something by writing a collection of standalone apps
instead of simple pluggable "things" that live inside a larger "thing". But
much of the EJB container's interception-based abilities, such as
persistence, simply go away when weaving the persistent code into the domain
code at compile time.
If you're interested in AOP, I *strongly* urge you to attend Xerox PARC's
AspectJ seminar on Friday, Jan 11th; see the AspectJ website for details.
Ted Neward
{.NET||Java} Course Author & Instructor
DevelopMentor (http://www.develop.com)
http://www.javageeks.com/tneward/index.html
> -----Original Message-----
> From: A mailing list for Enterprise JavaBeans development
> [mailto:[EMAIL PROTECTED]]On Behalf Of John Harby
> Sent: Thursday, December 20, 2001 8:39 AM
> To: [EMAIL PROTECTED]
> Subject: [EJB-INT] Container theory
>
>
> It seems that there are many special requirements for containers (which
> could be called frameworks by some), by IT customers. Around 1995, PARC
> Xerox began publishing information about Aspect Oriented Programming which
> from the engineering perspective provides a methodology for weaving
> declarative functionality into an application. It would be interesting to
> wonder if in the future containers will be completely customizable. There
> could be the abstract container and the EJB container as we know it as an
> instance thereof - vendors could provide additional declarative services
> such as logging that could be "weaved" into the container.
>
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