GH-1817: Allow Annotation Attribute Modification #1818
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| ? ((Class<?>) element).getSimpleName() | ||
| : ((Method) element).getDeclaringClass().getSimpleName() | ||
| + "." + ((Method) element).getName())); | ||
| return AnnotationUtils.synthesizeAnnotation(attrs, KafkaListener.class, null); |
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Let's revise this solution and push such a "hard" logic back to the framework!
I guess the same could be done with that AnnotationUtils.getAnnotationAttributes(ann) in the beginning.
I mean the contract of the enhancer would be like BiFunction<Map<String, Object>, AnnotatedElement, Map<String, Object>> - and the rest we would do internal ourselves!
Also: the KafkaListenerAnnotationBeanPostProcessor is a single instance in the application context.
Wouldn't it be easier for end-user just to provide such an enhancer bean and that's it. I mean it might have to be some more specific type, rather then just BiFunction. Although it might extend that interface anyway.
Then the framework would just take such a bean from the application context instead of requiring "hard core" for the whole KafkaListenerAnnotationBeanPostProcessor definition when we need just only a natural DI behavior with user-provided strategy in the application context.
Does it make sense?
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Good points - will rework.
| * @since 2.7.2 | ||
| * | ||
| */ | ||
| public interface AnnotationEnhancer extends BiFunction<KafkaListener, AnnotatedElement, KafkaListener> { |
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OK. You have introduced a more specific type, but you don't mention it in the docs I've commented above.
Thanks
| } | ||
| ---- | ||
| ==== | ||
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| IMPORTANT: `AnnotationEnhancer` bean definitions cannot be declared in the same class as a `@KafkaListener` method (or class). | ||
| It will prevent those listeners from being found by the `KafkaListenerAnnotationBeanPostProcessor`. |
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Probably better to say that such a bean must be declared static since it is used from the BeanPostProcessor?
Or... The logic in the KafkaListenerAnnotationBeanPostProcessor must be reworked from that InitializingBean.
We probably can collect AnnotationEnhancer beans in the beginning of the afterSingletonsInstantiated() impl...
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That is where I had it initially, but it is too late. The beans have all been preprocessed by then. I will look to see if static helps tomorrow.
Resolves #1817