RE:RESOLVED [aspectj-users] Use null for args in pointcut

["Conway. Fintan (IT Solutions)" <Fintan.Conway@xxxxxx>]

Hi Guys,

Thanks for your comments.  They have led me down the right path.

I was using to pointcut to exposed elements of the joinpoint that I
needed to access in my advice, instead of using the pointcut to specify
the joinpoints that I needed.

I had already used thisJoinPointStaticPart in the advice and was trying
to the arguments with it.

I realise now that I should have been using thisJoinPoint in the advice
to get the method names and the arguments to the methods.  The solution
was to change thisJoinPointStaticPart to thisJoinPoint, not pass the
arguments as parameter but to use thisJoinPoint.getArgs() instead.

This fully covers what I wanted to do.

Thanks again,

Fintan

-----Original Message-----
From: aspectj-users-bounces@xxxxxxxxxxx
[mailto:aspectj-users-bounces@xxxxxxxxxxx] On Behalf Of Ron Bodkin
Sent: 21 August 2006 20:30
To: aspectj-users@xxxxxxxxxxx
Subject: RE: [aspectj-users] Use null for args in pointcut


I agree with Wes's question about the contract. To me, it's a little
doubtful what you are trying to accomplish with args in your observer.
It seems like you are writing special-case logic for
thisJoinPoint.getArgs(), to match zero or one argument. What do you
expect to do with the first argument, if any? What would you do in a
case with more than one argument? Would thisJoinPoint.getArgs() meet
your needs?

There have been a number of requests for enhancement relating to
pointcut bindings. One that seems relevant for this request is
https://bugs.eclipse.org/bugs/show_bug.cgi?id=92889, which would allow
binding constants (so you could supply a constant value in cases where
e.g., null makes sense). In general, I think AspectJ 1.6.0 could benefit
from providing more power in unifying (binding and matching) for user
pointcuts, e.g., also bug #108895 and bug #106166. 

HTH,
Ron

-----Original Message-----
From: aspectj-users-bounces@xxxxxxxxxxx
[mailto:aspectj-users-bounces@xxxxxxxxxxx] On Behalf Of Wes
Sent: Monday, August 21, 2006 10:57 AM
To: aspectj-users@xxxxxxxxxxx
Subject: Re: [aspectj-users] Use null for args in pointcut

Hi -

If the variable is declared in the pointcut, it must be bound, but you
don't have to bind it using args(..), e.g.,

  target(subject) && target(arg)

But that sort of begs the question.  The abstract pointcut is supposed
to define a contract that implementors comply with, and you have no way
to comply with it since there is no argument for your join point.  If
you pretend to comply, it's not clear what's going to happen.  Here you
might have the source for the abstract aspect and understand the advice
on the join points picked out by the abstract pointcuts, but often 
programmers don't, and they don't know what would be the effect of not
complying.  

hmm.  Interesting!

Wes

------------Original Message------------
From: "Conway. Fintan (IT Solutions)" <Fintan.Conway@xxxxxx>
To: aspectj-users@xxxxxxxxxxx
Date: Mon, Aug-21-2006 7:31 AM
Subject: [aspectj-users] Use null for args in pointcut
Hi *,

I have a problem where I have to extend a pointcut in a super aspect.
The signature of this pointcut is as follows : protected abstract
pointcut subjectChange(Subject s, Object args); 
One of the aspects which extends this super aspect does not require the
'args'  parameter. My overriding pointcut looks like : protected
pointcut subjectChange(Subject subj, Object arg) : (
call(* Pot.add(..))
|| 
call(* Pot.refresh())
)
&& !within(PotObserverUtilTest)
&& target(subj)
&& args(arg); 
This pointcut matches the Pot.add method, since it does have an
argument. However the Pot.refresh() method is not advised since it does
not have any arguments.  I have to override the abstract pointcut. Is
there any way to get the Pot.refresh() advised in this scenario?  (args
=
null?)
Any advice gratefully appreciated,
Fintan 


_______________________________________________
aspectj-users mailing list
aspectj-users@xxxxxxxxxxx
https://dev.eclipse.org/mailman/listinfo/aspectj-users


* ** *** ** * ** *** ** * ** *** ** * 
This email and any files transmitted with it are confidential and 
intended solely for the use of the individual or entity to whom they 
are addressed. 
Any views or opinions presented are solely those of the author, and do not necessarily  represent those of ESB. 
If you have received this email in error please notify the sender. 
 
Although ESB scans e-mail and attachments for viruses, it does not guarantee 
that either are virus-free and accepts no liability for any damage sustained 
as a result of viruses. 
 
* ** *** ** * ** *** ** * ** *** ** *