Re: [aspectwerkz-user] Re-visitng AspectWerkz

The following is perhaps a good start to look at
http://aspectwerkz.codehaus.org/new_features_in_2_0.html#Per_instance_interception

I ll see some more on monday how each of your requirements can be adressed.
Alex

On 4/22/05, [email protected]
<[email protected]> wrote:
> 
> 
> Hello All
> 
>  
> 
> I'm re-visiting AW after quite sometime, the last release I used was AW 0.9
> but after that the aspect/interceptor strategy changed a little bit and was
> not accommodating to my requirements. I would like to state my scenario and
> would be greatly helpful if someone could tell me if it is possible or not
> and point me in the right direction.
> 
>  
> 
> I use the term "interceptor" instead of "aspect" (that are self-contained in
> AW) because in my case the "binding" of an advice to one or more pointcuts
> should be external or at least easy to accomplish without having to
> re-deploy the aspect.
> 
>  
> 
> We are using AOP as a "tool" and not as "coding style" for the purposes of
> policy enforcement on our EJBs. Our policy enforcement mechanism is expected
> to allow binding at run-time any number of "interceptors" to one or more
> "pointcuts" where these pointcuts would basically reflect individual
> operations on the EJB. Similarly there should be capability to detach these
> interceptor bindings and swap them for something else. It would be a bonus
> if there was a capability to compose one or more commonly used interceptors
> inside a stack and attaching this stack to a pointcut. 
> 
>  
> 
> a)       At deployment time of the EJB I would like to pre-compile the
> classes based on the pointcuts which are one for each of the operations.
> There may be some or no interceptor binding definitions at this point but in
> essence "preparing" the target to accommodate interceptors for the future.
> 
> b)       To be able to deploy a new "interceptor" at run-time which means
> class-loading the code, etc and make it available for attaching and
> detaching them to already "deployed" pointcuts.
> 
> c)       To be able to swap one or more interceptors at run-time from
> pointcut binding. This is basically the capability to attach and detach
> interceptors to and from pointcuts that are essentially EJB operations. And
> at the time of the service invocation, the effect of interception is
> realized instantly.
> 
> d)       To be able to define one or more attributes/parameters on an
> Interceptor that is nothing but ad-hoc name-value pairs and should be
> visible inside the interceptor code.
> 
> e)       To be able to define one or more attributes/parameters as
> "meta-data" at the class and method level and there should be a capability
> to read this meta-data from within the interceptor code assuming it is bound
> to the right pointcut.
> 
> f)         To be able to "name" interceptors borne out of the same class so
> that I could create an "Interceptor1(class=com.xyz.Interceptor) and
> Interceptor2(class=com.xyz.Interceptor) and have different attribute values
> for each of them to be used for different purposes.
> 
>  
> 
> I was able to do a good deal of this in AW 0.9 but the strategy considerably
> changed after that and I switched to JBoss-AOP which allowed me to do all of
> this. But for various reasons I'm also interested in AW considering there is
> a lot of interest around it and with AspectJ integration. 
> 
>  
> 
> It wasn't obvious to me as to what I can or cannot do with 2.0. Your
> analysis and inputs are greatly appreciated.
> 
>  
> 
> Thanks
> 
> Rajiv Kadayam
> 
>