Skip to main content
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [List Home]
Re: AW: [aspectj-users] Overriding pointcuts 
Hi Sven,

Thanks to Matthew for providing the complete working code.

The message you got reminds me of a known bug:

  https://bugs.eclipse.org/bugs/show_bug.cgi?id=113447

Wes


> ------------Original Message------------
> From: "Sven Apel" <apel@xxxxxxxxxxxxxxxxxxxxxxx>
> To: "'Wes Isberg'" <wes@xxxxxxxxxxxxxx>, aspectj-users@xxxxxxxxxxx
> Date: Mon, Oct-24-2005 0:41 AM
> Subject: AW: [aspectj-users] Overriding pointcuts
>
> Hi Wes,
> 
> Back to my office I tried your solution but I got a runtime exception 
> (the
> same that I described in a previous mail):
> 
> Exception in thread "main" java.lang.VerifyError: (class: Fifo, method: 
> Get
> signature: ()LValue;) Unable to pop operand off an empty stack
> 
> Is this a bug or not?
> 
> Regards
> 
> Sven
> 
> > -----Ursprüngliche Nachricht-----
> > Von: aspectj-users-bounces@xxxxxxxxxxx [mailto:aspectj-users-
> > bounces@xxxxxxxxxxx] Im Auftrag von Wes Isberg
> > Gesendet: Samstag, 22. Oktober 2005 00:43
> > An: aspectj-users@xxxxxxxxxxx
> > Betreff: RE: [aspectj-users] Overriding pointcuts
> > 
> > > The problems arise when I have
> > > pointcuts
> > > that expect arguments, as in the fifo example.
> > 
> > For me your code works when fifo is bound in all legs of the 
> pointcut:
> > 
> > ----
> > aspect ExtLogging extends Logging {
> >   pointcut log(Fifo fifo) : Logging.log(fifo) ||
> >     (this(fifo) && execution(* Fifo.Get(..)));
> > }
> > ----
> > 
> > Wes
> > 
> > 
> > 
> > > ------------Original Message------------
> > > From: apel@xxxxxxxxxxxxxxxxxxxxxxx
> > > To: "Wes Isberg" <wes@xxxxxxxxxxxxxx>, rbodkin@xxxxxxxxxxxxxx, 
> aspectj-
> > users@xxxxxxxxxxx
> > > Date: Fri, Oct-21-2005 1:34 PM
> > > Subject: RE: [aspectj-users] Overriding pointcuts
> > >
> > > Hi Wes and Rod,
> > >
> > > I know that this example works. The problems arise when I have
> > > pointcuts
> > > that expect arguments, as in the fifo example.
> > >
> > > By the way, in a recent paper we propose the notion of aspect
> > > refinement:
> > > http://wwwiti.cs.uni-magdeburg.de/~apel/AOASIA2005.pdf
> > > With aspect refinement it is possible to use the "super" keyword to
> > > refer
> > > to the parent pointcuts. In this way we can extend or constrain the 
> set
> > > of
> > > join points using a subsequent subaspect. Unfortunately, this is
> > > currently
> > > implemented in FeatureC++/AspectC++ only:
> > > http://wwwiti.cs.uni-magdeburg.de/iti_db/forschung/fop/featurec/
> > > Currently, we work on a version for AspectJ, using the abc. In 
> fact, I
> > > ask
> > > these questions to get insight in the semantics of AspectJ to 
> implement
> > > aspect refinement in AspectJ. In an upcoming report we explain more
> > > details about our extension of AspectJ, including the things about
> > > pointcuts (we plan to publish the report next week).
> > >
> > > best regards
> > >
> > > Sven
> > >
> > >
> > > > Oh, good.  You're right that non-abstract pointcuts can also be
> > > overridden
> > > > and not just hidden (meaning the superaspect uses the subaspect
> > > > declaration) - when the (implicit) reference is not a class.
> > > > Note in this light that you can refer directly to the superaspect
> > > > pointcut using a class/type reference:
> > > >
> > > > ----
> > > > abstract aspect AA {
> > > >     pointcut pc() : execution(void main(String[]));
> > > >     before() : pc() { System.out.println("jp: " + thisJoinPoint); 
> }
> > > > }
> > > > aspect A extends AA {
> > > >     // AA.pc() refers to superaspect pointcut
> > > >     pointcut pc() : AA.pc() || (withincode(void main(String[]))
> > > >         && call(void PrintStream.println(String)));
> > > > }
> > > > ----
> > > >
> > > > It's too bad that using super as a reference is illegal:
> > > >
> > > > ----
> > > >     // error
> > > >     pointcut pc() : super.pc() || ...
> > > > ----
> > > >
> > > > It's when the pointcut reference is a class/type that hiding
> > > > comes into play, and can support a limited form of redeclaration
> > > > for external (class-reference) clients, e.g., of a library:
> > > >
> > > >
> > > 
> http://eclipse.org/aspectj/sample-code.html#library-classPointcutLibrary
> > > >
> > > > I'll document this somewhere, as long as Andrew/Adrian/Erik, et 
> al
> > > > don't say it's accidental.
> > > >
> > > > Wes
> > > >
> > > >> ------------Original Message------------
> > > >> From: "Ron Bodkin" <rbodkin@xxxxxxxxxxxxxx>
> > > >> To: "'Wes Isberg'" <wes@xxxxxxxxxxxxxx>, 
> aspectj-users@xxxxxxxxxxx
> > > >> Date: Fri, Oct-21-2005 11:24 AM
> > > >> Subject: RE: [aspectj-users] Overriding pointcuts
> > > >>
> > > >> Thatâ&#8364;&#8482;s not how I read the 
> programmerâ&#8364;&#8482;s
> > > guide. From
> > > >>
> > > http://www.eclipse.org/aspectj/doc/released/progguide/semantics-
> > pointcuts.ht
> > > >> ml
> > > >>
> > > >> "Pointcuts that are not final may be declared abstract, and 
> defined
> > > >> without
> > > >> a body. Abstract pointcuts may only be declared within abstract
> > > >> aspects.
> > > >>   abstract aspect A {
> > > >>       abstract pointcut publicCall(int i);
> > > >>   }
> > > >>
> > > >> In such a case, an extending aspect may override the abstract
> > > pointcut.
> > > >>
> > > >>   aspect B extends A {
> > > >>       pointcut publicCall(int i): call(public Foo.m(int)) &&
> > > args(i);
> > > >>   }
> > > >> For completeness, a pointcut with a declaration may be declared
> > > final.
> > > >>
> > > >> Though named pointcut declarations appear somewhat like method
> > > >> declarations,
> > > >> and can be overridden in subaspects, they cannot be overloaded. 
> It
> > > is
> > > >> an
> > > >> error for two pointcuts to be named with the same name in the 
> same
> > > >> class or
> > > >> aspect declaration. "
> > > >>
> > > >> Notice that pointcut declarations can be overridden in 
> subaspects.
> > > The
> > > >> sentence does not limit them to abstract pointcuts.
> > > >>
> > > >> Moreover, the feature works as I read the description and I have
> > > found
> > > >> it
> > > >> useful as in my earlier posting about how I used pointcut 
> overriding
> > > >> for the
> > > >> glassbox inspector. Here is a simple xample:
> > > >>
> > > >> public abstract aspect Base {
> > > >>     public pointcut methodExec();
> > > >>     before() : methodExec() {
> > > >> 	System.out.println("advised by "+this);
> > > >>     }
> > > >>
> > > >>     public static void main(String args[]) {}
> > > >> }
> > > >>
> > > >> aspect Derived1 extends Base {
> > > >>     public pointcut methodExec() : execution(* main(..));
> > > >> }
> > > >>
> > > >> aspect Derived2 extends Base {}
> > > >>
> > > >> C:\devel\scratch\override>ajc Base.aj
> > > >>
> > > >> C:\devel\scratch\override>java Base
> > > >> advised by Derived1@12c1c0
> > > >>
> > > >>
> > > >>
> > > >>
> > > >> ________________________________________
> > > >> From: aspectj-users-bounces@xxxxxxxxxxx
> > > >> [mailto:aspectj-users-bounces@xxxxxxxxxxx] On Behalf Of Wes 
> Isberg
> > > >> Sent: Friday, October 21, 2005 10:56 AM
> > > >> To: aspectj-users@xxxxxxxxxxx
> > > >> Subject: Re: [aspectj-users] Overriding pointcuts
> > > >>
> > > >> Also, Pointcuts are like static methods: they can be hidden but 
> not
> > > >> overridden.
> > > >> And you cannot overload a pointcut name (e.g., with more or 
> fewer
> > > >> variables).
> > > >> Â
> > > >> In this case the advice in the abstract aspect will run only on 
> the
> > > >> join
> > > >> points picked out
> > > >> by the pointcut in the abstract aspect.  the pointcut in the
> > > subaspect
> > > >> does
> > > >> not override
> > > >> but hides the superaspect pointcut of the same name (indeed, I
> > > thought
> > > >> we
> > > >> had an
> > > >> XLint warning for this.)
> > > >> Â
> > > >> Normally the pointcut in the abstract aspect is itself abstract, 
> for
> > > >> just
> > > >> this reason.Â
> > > >> Some people use the convention of another  pointcut titled
> > > >> {name}_default to
> > > >>
> > > >> offer reusable pointcut for subaspects to consider.
> > > >> Â
> > > >> Wes
> > > >> Â
> > > >> ------------Original Message------------
> > > >> From: Thiago Bartolomei <thiagobart@xxxxxxxxx>
> > > >> To: aspectj-users@xxxxxxxxxxx
> > > >> Date: Fri, Oct-21-2005 3:54 AM
> > > >> Subject: Re: [aspectj-users] Overriding pointcuts
> > > >> Hi,
> > > >>
> > > >> try to append target to your pointcut:
> > > >>
> > > >> pointcut log(Fifo fifo) : Logging.log(fifo) || execution(*
> > > >> Fifo.Get(..)) &&
> > > >> target(fifo);
> > > >>
> > > >> I think the problem is that the compiler needs to know what to 
> do
> > > with
> > > >> your
> > > >> fifo variable in all cases . Without the target, the second part 
> of
> > > the
> > > >> "or"
> > > >> would have no context exposure..
> > > >>
> > > >> []s
> > > >> Thiago T. Bartolomei
> > > >> On 10/21/05, Sven Apel <apel@xxxxxxxxxxxxxxxxxxxxxxx> wrote:
> > > >> Hi,
> > > >>
> > > >> I have a problem with overriding and reusing pointcuts. I want 
> to
> > > >> extend the
> > > >> set of join points captured by the "log" pointcut in the aspect
> > > >> "Logging":
> > > >>
> > > >> abstract public aspect Logging
> > > >> {
> > > >>         pointcut log(Fifo fifo) : execution(* 
> Fifo.Put(..))
> > > &&
> > > >> target(fifo);
> > > >>
> > > >>         before(Fifo fifo) : log(fifo)
> > > >>         {
> > > >>                 System.out.println("---> Fifo 
> method
> > > >> called");
> > > >>         }
> > > >> }
> > > >>
> > > >> For that I want to use a further aspect that inherits from
> > > "Logging":
> > > >>
> > > >> public aspect ExtLogging extends Logging
> > > >> {
> > > >>         pointcut log(Fifo fifo) : Logging.log(fifo) ||
> > > >> execution(*
> > > >> Fifo.Get(..));
> > > >> }
> > > >>
> > > >> The above example does not work because ajc cannot bind "fifo"
> > > >> (inconsistent
> > > >> binding).
> > > >>
> > > >> The following example also does not work:
> > > >>
> > > >> public aspect ExtLogging extends Logging
> > > >> {
> > > >>         pointcut log() : Logging.log(Fifo) || 
> execution(*
> > > >> Fifo.Get(..));
> > > >> }
> > > >>
> > > >> This is because "ExtLogging.log" must have the same signature 
> than
> > > >> "Logging.log". Other variants that declare an argument list in
> > > >> "ExtLogging.log" but do not pass "fifo" to "Logging.log" also do 
> not
> > > >> work
> > > >>
> > > >> Is there a possibility to override and reuse parent pointcuts 
> that
> > > >> expect
> > > >> arguments? Without arguments the above example works!
> > > >>
> > > >> Thanks in advance
> > > >>
> > > >> Sven
> > > >>
> > > >> --
> > > >> Dipl.-Inf. Sven Apel
> > > >> Institute for Technical and Business Information Systems
> > > >> Otto-von-Guericke-University
> > > >> P.O. Box 4120, D-39016 Magdeburg, Germany
> > > >> Phone: ++49 (391) 67-11899, Fax: ++49 (391) 67-12020
> > > >> Room: 29/108
> > > >> E-Mail: apel@xxxxxxxxxxxxxxxxxxxxxxx
> > > >>
> > > >>
> > > >>
> > > >>
> > > >> _______________________________________________
> > > >> aspectj-users mailing list
> > > >> aspectj-users@xxxxxxxxxxx
> > > >> https://dev.eclipse.org/mailman/listinfo/aspectj-users
> > > >>
> > > >> _______________________________________________
> > > >> aspectj-users mailing list
> > > >> aspectj-users@xxxxxxxxxxx
> > > >> https://dev.eclipse.org/mailman/listinfo/aspectj-users
> > > >>
> > > >> _______________________________________________
> > > >> aspectj-users mailing list
> > > >> aspectj-users@xxxxxxxxxxx
> > > >> https://dev.eclipse.org/mailman/listinfo/aspectj-users
> > > >>
> > > >
> > > > _______________________________________________
> > > > aspectj-users mailing list
> > > > aspectj-users@xxxxxxxxxxx
> > > > https://dev.eclipse.org/mailman/listinfo/aspectj-users
> > > >
> > >
> > >
> > > _______________________________________________
> > > aspectj-users mailing list
> > > aspectj-users@xxxxxxxxxxx
> > > https://dev.eclipse.org/mailman/listinfo/aspectj-users
> > >
> > 
> > _______________________________________________
> > aspectj-users mailing list
> > aspectj-users@xxxxxxxxxxx
> > https://dev.eclipse.org/mailman/listinfo/aspectj-users
> 
> _______________________________________________
> aspectj-users mailing list
> aspectj-users@xxxxxxxxxxx
> https://dev.eclipse.org/mailman/listinfo/aspectj-users
>

Back to the top