[aspectj-users] Dynamically defining fields

[Keven Ring <keven@xxxxxxxxx>]

 I have a software project where we are attempting to allieviate some 
of the responsibility from the end-user by automatically defining some 
static, final fields in their code, based on other declarations made in 
their software.  These declarations are in the form of user-defined 
methods that follow a particular pattern.  For each method that matches 
that pattern, we would like to define a field in their class to 
correspond with that method name.

 The effect that we are looking for could be provided with C-like 
pre-processors, however, we are already utilizing aspects for other 
areas of the project.  Thus, rather than adding a new tool, we would 
prefer to re-utilize an existing one, in this case, AJC.

 There are two problems as I see it:
1) For this particular problem, we are interested in method 
declarations, versus method invocations
2) We do not need to modify the code in the method declaration, but we 
want to add code in the class (in this case, primitive class variables), 
and what we want to add is not know apriori.

I would love to be able to write something such as the following:

pointcut actionMethod(MyBaseClass mbc) : declare (void 
MyBaseClass+.action*(..)) && target(mbc) {
 // Get the name of the method
 String name = thisJoinPoint.getSignature().getName();

 // Strip off the "action" designator
 name = name.substring(5);

 // Declare a variable in this class with the name of the method
 thisJoinPoint.addTypeDeclaration("public static final int _"+name+" = 
5;");
}

My (basic) understanding of Aspects at this point says that this isn't 
possible.  Does anyone have thoughts on how a similar capability might 
be accomplished, either with the current AJC, or with modifications to AJC?

Thanks in advance!

--
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