Introduce `@Spel` annotation to denote which methods accept SpEL expressions

[kalgon]

Would it be possible to annotate an annotation member which accepts a spel expression with @Spel to let IDEs know that this member can be evaluated? Maybe the @Spel annotation could indicate if expressions may reference beans, method parameters, etc.

If this mechanism is in place, third-party annotations could have their expressions validated by IDEs and it would simplify the IDEs' work by having a single general solution instead of implementing ad-hoc validations per annotation.

@interface Spel {
    enum Access {
        APPLICATION_CONTEXT, METHOD_PARAMETERS
    }
    Access[] access() default {};
}

@interface Locked {
    @Spel(access = {METHOD_PARAMETERS})
    String lockName(); 
}

class MyService {
    @Locked(lockName = "taskLock-#{#taskId}")
    void doSomethingThatMustBeLocked(long taskId, ...) { ... }
}

[sbrannen]

Hi @kalgon,

Thanks for the proposal; however, we have no plans to introduce any kind of @Spel annotation or declarative means to denote which parts of an application may be used in a SpEL expression. In addition, the Spring Framework and Spring portfolio projects would not make use of such a mechanism. Consequently, such custom annotations (as well as the processing of such annotations) is best left to applications or custom frameworks.

In light of that, I am closing this issue.