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Tue, 24 January 2006 11:40

Eclipse User

Hi,

I'm testing the usage of Aspectj and encountered a problem.

I wrote the following code:

public aspect myAspect{

pointcut publicMethods() : execution(public * myMain.func(..));

pointcut logObjectCalls() : execution(* Logger.*(..));

pointcut loggableCalls() : publicMethods(); //l&& ! logObjectCalls();

before() : loggableCalls(){

Logger.entry(thisJoinPoint.getSignature().toString());

}

after() : loggableCalls(){

Logger.exit(thisJoinPoint.getSignature().toString());

}

void around(): call(public void myMain.func(String)){

if(Math.random() > .5){

System.out.println("> 0.5");

proceed(); //go ahead with the method call

}

else{

System.out.println("< 0.5");

}

}

}

The function FUNC of MYMAIN class has only one argument which is of String
type.

What I would like to achieve is that I will be able to check the input
parameters in the AROUND advice.

Thanks in advance,

Asaf Lahav

Re: around advice question [message #61345 is a reply to message #61290]

Wed, 25 January 2006 10:35

Eclipse User

Hi Asaf,

My first attempt at an AspectJ solution, so hopefully this is right!

Think what looking for is the args designator. Heres a snip for you

public class AnObject {

public String doSomethingStringy (String string){
return string+"added by method";
}

public static void main(String[] args){

AnObject obj = new AnObject();

System.out.println(obj.doSomethingStringy("Original"));

}
}

public aspect AnAspect {

pointcut effectDoSomething(String string) : call(public String
AnObject.doSomethingStringy (String)) && args(string);

String around(String string) : effectDoSomething(string){

string = string+" added before ";
string = proceed(string);
string = string+" added after";
return string;
}
}

Outputs:

Original added before added by method added after

As you can see this makes the parameters availible in your advice block
for manipulation/testing. Hopfully thats what your looking for!

Enjoy

Tom

Re: around advice question [message #61369 is a reply to message #61345]

Thu, 26 January 2006 03:54

Eclipse User

Thanks tom...
it helped allot.

Re: around advice question [message #591978 is a reply to message #61290]

Wed, 25 January 2006 10:35

Eclipse User