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Re: [aspectj-users] How to rewrite a class with AspectJ 
I've only looked at it quickly, but first thing I spot is you haven't
used '..' in the within clause.

within(@Observable com.*)

will match packages com.Foo, com.Bar, it will not match
com.somewhere.Foo or com.somewhere.else.Bar.  I doubt that is what you
want so change it to double dot.

within(@Observable com..*)

Also I see you using @annotation(Event) - did you really need a
dynamic match on that?  If you don't you could just statically match
it by remove the @annotation clause and putting the annotation in the
execution pointcut:

execution(@Event * *.*(..))

Andy

On 25 April 2010 02:17, Mohammad Norouzi <mnrz57@xxxxxxxxx> wrote:
> Hi Simone,
> Can you please tell me what's wrong with this pointcut. I want all the
> methods which is in a type annotated with @Observable and the method itself
> annotated with @Event
>
> @Observable
> public class O1 {
>
>    @Event(value = {"EVENT1","EVENT2"})
>    public void method1(String str) {
>
>    }
> }
>
> package com.foo.aspect;
>
> import com.foo.annotation.*;
>
> public aspect EventDispatcherAspect {
>
>         pointcut eventMethods(Object obj,Object iparam) :
>             within(@Observable com.*)
>         &&    execution(* *.*(..))
>         && @annotation(Event)
>         && args(iparam)
>         && target(obj);
>
>         after(Object obj,Object iparam) returning: eventMethods(obj,iparam)
> {
>
> System.out.println("thisJoinPoint:"+thisJoinPointStaticPart.toLongString());
>
> System.out.println("thisJoinPointSig:"+thisJoinPointStaticPart.getSignature().toLongString());
>             //System.out.println("Events: "+e.value());
>
>         }
> }
>
>
> Regards,
> Mohammad
> --------------------------
>
> On Wed, Apr 21, 2010 at 4:51 PM, Simone Gianni <simoneg@xxxxxxxxxx> wrote:
>>
>> Hi Mohammad,
>> nope, unfortunately AspectJ is not able to declare fields "dynamically",
>> moreover private fields injected by AspectJ have a number of limitations
>> that are being solved (they have mangled names).
>>
>> What you can do however is :
>> - Declare an interface WithObserverABC
>> - Use an ITD to place a privare field on that interface
>> - Inject that interface on all classes that have @Observable
>> - Write the aspect that calls the observer method when an @Observable
>> method is executed.
>>
>> public aspect InjectObserverABC {
>>   public interface WithObserverABC {}
>>
>>   // this could be private, except for name mangling, depends on AspectJ
>> version
>>   public ObserverAbc WithObserverABC.abcObserver = new ObserverABCImpl();
>>
>>   // you could narrow this
>>   declare parents : hasmethod(@Observable *(..)) implements
>> WithObserverABC;
>>
>>   before(WithObserverABC instance) : execution(@Observable *
>> WithObserverABC+.*(..)) && this(instance) {
>>     instance.abcObserver.
>> notifyObserver();
>>   }
>> }
>>
>> I'm not sure about the syntax (I wrote it here in this email, and i need
>> compiler support when writing pointcuts :) ), but you should get the idea.
>> Eventually you can try to play with generics/abstract aspects to make it
>> easier to inject new observers, but I cannot think of a way of doing this
>> completely automatically (apart from using APT to parse classes with
>> @Observer and generate dynamically aop.xml to instantiate concrete aspects
>> ... but that's another story :) )
>>
>> Hope this helps,
>> Simone
>>
>> 2010/4/20 Mohammad Norouzi <mnrz57@xxxxxxxxx>
>>>
>>> Hi Simone,
>>> >>if I understand correctly, when a method annotated with @Observable is
>>> >> executed, you want to see if there are fields in that class with an instance
>>> >> of an observer, and call a method on the observer.<<
>>> Actually, when a method is annotated with @Observable (before executing
>>> and at the time of compiling codes) I want to add (not see) those interfaces
>>> that annotated with @Observer, as  private fields in the observable and I
>>> want to add them because both observer and observable are EJB session beans
>>> so the application server will take the burden of instantiating those
>>> observers using its injection technique
>>>
>>> What I need is something like this:
>>> for(MyObserver o : observers){
>>>    declare a private field with a name in this instance of observable
>>> class
>>> }
>>>
>>>
>>> On Mon, Apr 19, 2010 at 2:22 PM, Simone Gianni <simoneg@xxxxxxxxxx>
>>> wrote:
>>>>
>>>> Hi Mohammad,
>>>> if I understand correctly, when a method annotated with @Observable is
>>>> executed, you want to see if there are fields in that class with an instance
>>>> of an observer, and call a method on the observer.
>>>>
>>>> You can use AspectJ to execute an advice before/after/around the
>>>> execution of @Obervable methods, and use thisJoinPoint or the this()
>>>> construct to find the instance of the method.
>>>>
>>>> Once you are there, you must use plain java reflection, and not AspectJ,
>>>> to find fields in that class that contains an observer and invoke observer
>>>> methods.
>>>>
>>>> To add @EJB annotation to all fields of type X where X is annotated with
>>>> @Observer, you can use declare @class and write a type pattern that uses
>>>> @Observer annotation. If @Observer annotation is placed on methods, you can
>>>> use hasmethod() to find classes that has such methods, but beware cause
>>>> hasmethod is somewhat experimental.
>>>>
>>>> Hope this helps,
>>>> Simone
>>>>
>>>> 2010/4/19 is_maximum <mnrz57@xxxxxxxxx>
>>>>>
>>>>> Thanks Simone, yes this is exactly what I want... but another question
>>>>> is
>>>>> that this is used using 'declare' and as far as I know declare is
>>>>> placed in
>>>>> aspect definition. How can I place it in a for-loop.
>>>>>
>>>>> Let me tell you the scenario may be I am in wrong way...
>>>>>
>>>>> I am trying to implement an observer pattern in EJB 3.0. I saw many
>>>>> implementation using aspectJ but mine is a little different. The
>>>>> difference
>>>>> is that I want to inject observer into observable...
>>>>>
>>>>> Because session beans are managed object and in my case both observer
>>>>> and
>>>>> observable supposed to be session beans I want application server
>>>>> injects
>>>>> observer session beans in observable SB and then call observer methods
>>>>>
>>>>> These observer and observable methods will be annotated by the
>>>>> developer
>>>>> with say @Observer and @Observable
>>>>>
>>>>> What I wanted was to look for @Observer methods and find their
>>>>> interface and
>>>>> put them like this:
>>>>>
>>>>> @EJB
>>>>> private ObserverInterface1 observer1
>>>>>
>>>>> than each time the determined method is called I can call
>>>>> observer1.notifyObserver() method
>>>>>
>>>>> Can you please help me on this?
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> Simone Gianni-2 wrote:
>>>>> >
>>>>> > Hi  Mohammad,
>>>>> > maybe you are loooking for the declare annotation statement?
>>>>> >
>>>>> > http://www.eclipse.org/aspectj/doc/next/adk15notebook/annotations-declare.html
>>>>> >
>>>>> > Simone
>>>>> >
>>>>> >
>>>>>
>>>>>
>>>>> -----
>>>>> --
>>>>> Regards
>>>>>
>>>>> Mohammad Norouzi
>>>>>
>>>>> Help each other to reach the future faster
>>>>>
>>>>> http://pixelshot.wordpress.com Pixelshot Photoblog
>>>>>
>>>>> http://brainable.blogspot.com Brainable Blog
>>>>>
>>>>>
>>>>> --
>>>>> View this message in context:
>>>>> http://old.nabble.com/How-to-rewrite-a-class-with-AspectJ-tp28280867p28287273.html
>>>>> Sent from the AspectJ - users mailing list archive at Nabble.com.
>>>>>
>>>>> _______________________________________________
>>>>> aspectj-users mailing list
>>>>> aspectj-users@xxxxxxxxxxx
>>>>> https://dev.eclipse.org/mailman/listinfo/aspectj-users
>>>>
>>>>
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>>>
>>>
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>>
>>
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>
>
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