Here are a few question-based article titles that fit the provided content: Directly addressing the problem: * Java Annotations: How to Dynamically Generate Values for Runtime Annotations? * Can Yo

Dynamic Generation of Java Annotation Values

This question explores the challenge of dynamically generating values ​​for Java annotations. The author wishes to annotate classes with values ​​derived from methods, but encounters an error while attempting to use a generated static final value.

The compiler enforces the requirement that annotation attribute values ​​must be constant expressions, as per the error message: "The value for annotation attribute MyInterface.aString must be a constant expression." This restriction stems from the fact that runtime annotations are evaluated during compilation, and generated values ​​are not available at that time.

Unfortunately, there is no ready-made solution for this problem method. For the RetentionPolicy.RUNTIME annotation, the compiler evaluates the annotation metadata at compile time, but GENERIC_GENERATED_NAME is still unknown at compile time. At the same time, the RetentionPolicy.SOURCE annotation is discarded after compilation, so these generated values ​​are never recognized.

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