AspectJ CTW aspects executed twice

[MnlK]

Affects: 6.1.7, 6.1.8

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We experience AspectJ aspects to be executed twice since updating to Spring-Boot 3.2.6 with Spring-Framework 6.1.8.

The @Aspect classes are used with AspectJ-CTW via aspectj-maven-plugin and we initialize them as spring bean with @Bean configuration.
Now they are automatically falsely initialized as Spring-AOP cglib proxy additionally to the already existing bean.

This means that calls are going first through the proxy-aspect and then through the CTW-aspect.

We also use Spring-AOP proxies for other aspects in the same project, so we can't just completely disable the AOP autoconfig.

This seems to be caused by #32793

[jhoeller]

Frankly, we did not expect such mixed AspectJ usage, at least not with the aspect exposed as a bean in the application context. I can see your scenario though. We'll try to make it work without breaking the original Micrometer use case - which is not trivial since AspectJ is trying to blur the lines between the different aspect types, suggesting ajc compilation for reusable aspect classes that can serve for CTW/LTW as well as for Spring AOP. Maybe we just make autodetection in the context more restrictive while still accepting any kind of AspectJ aspect when explicitly passed into a ProxyFactory.

[jhoeller]

It looks like we can simply skip target classes that have been compiled with ajc for aspects that have also been compiled with ajc - since in that case, the AspectJ compiler has clearly weaved the target class already. I'll roll that into 6.1.9 / 6.0.22 / 5.3.37.