Re: [aspectj-users] Proceeding with all arguments in native syntax

["Alexander Kriegisch" <alexander@xxxxxxxxxxxxxx>]

Bug 233718 is not really what I was concerned about.

Casting thisJoinPoint to ProceedingJoinPoint was an idea I also had
before, but the subsequent proceed(args) call returns null. If you run
this aspect in native syntax against the sample classes in my SO
answer...

package de.scrum_master.aspect;

import java.lang.annotation.Annotation;
import java.lang.reflect.Method;

import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.SoftException;
import org.aspectj.lang.reflect.MethodSignature;

import de.scrum_master.app.Scrubbed;

public aspect StringScrubberAspect {
  Object around() : call(public * *(.., @de.scrum_master.app.Scrubbed (String), ..)) {
    Method method = ((MethodSignature) thisJoinPoint.getSignature()).getMethod();
    Object[] args = thisJoinPoint.getArgs();
    Annotation[][] parameterAnnotations = method.getParameterAnnotations();
    for (int argIndex = 0; argIndex < args.length; argIndex++) {
      for (Annotation paramAnnotation : parameterAnnotations[argIndex]) {
        if (paramAnnotation instanceof Scrubbed)
          args[argIndex] = scrubString((String) args[argIndex]);
      }
    }
    try {
      System.out.println(thisJoinPoint instanceof ProceedingJoinPoint);
      Object result = ((ProceedingJoinPoint) thisJoinPoint).proceed(args); 
      System.out.println(result);
      return result;
    } catch (Throwable t) {
      throw new SoftException(t);
    }
  }

  private String scrubString(String string) {
    return string.replaceAll("[Ee]", "#");
  }
}

... the console log will be:

true
null
true
null

How about extending 'args()' functionality in order to allow binding to
an Object[] parameter which does not occur anywhere in the pointcut
literal, automatically binding the equivalent of JoinPoint.getArgs() to
it and thus allowing to proceed with the same bound parameter in both
native and @AspectJ syntax? That would be kind of elegant, probably
manageable from the perspective of pointcut parsing because there is no
really new syntax, and the functionality to proceed with an Object[] is
already in the code base, which is why it works in @AspectJ syntax.

-- 
Alexander Kriegisch
https://scrum-master.de


Andy Clement schrieb am 05.09.2020 02:05 (GMT +07:00):

> I feel like there are some bugs that talk around this topic, but I
> can't quite find the one I'm thinking of. I found
> https://bugs.eclipse.org/bugs/show_bug.cgi?id=233718 and it was
> interesting to read what I was writing 12 years ago :) I feel like i
> prototyped an improved arg matching system but I hit something
> seriously complex before finishing, and wrote about it in bugzilla
> somewhere...
> 
> I don't think you are missing anything. Mixing the syntaxes should be
> ok I think. Can you cast thisJoinPoint to a ProceedingJoinPoint in
> AspectJ syntax around advice and use it? I can't quite remember.
> 
> 
> On Thu, 3 Sep 2020 at 22:41, Alexander Kriegisch wrote:
> 
>> Check this out:
>> https://stackoverflow.com/a/63735393/1082681
>> 
>> Is there anything I have overlooked? If so, how would I do that in
>> native syntax? If not, would it be hard to implement?