Configuration Metadata for Actuator endpoints do not take Nullness into account

[snicoll]

We have missed updating org.springframework.boot.configurationprocessor.ConfigurationMetadataAnnotationProcessor#isOptionalParameter. This also checks for Spring Framework's @Nullable. Problem here is that we can't rely on Nullness, as the annotation processor has no dependencies.

Originally posted by @mhalbritter in #46593

[mhalbritter]

This will trigger the annotation type use bug in the JDK, which is only fixed in JDK 24 right now.

@sdeleuze said:

to get TYPE_USE annotations discovered I did:

AnnotationMirror getAnnotation(Element element, String type) {
    if (element != null) {
        for (AnnotationMirror annotation : element.getAnnotationMirrors()) {
            if (type.equals(annotation.getAnnotationType().toString())) {
                return annotation;
            }
        }
        for (AnnotationMirror annotation : element.asType().getAnnotationMirrors()) {
            if (type.equals(annotation.getAnnotationType().toString())) {
                return annotation;
            }
        }
    }
    return null;
}

[wonyongg]

Hi, I’ve read through this issue and thought it would be a good opportunity to contribute, so I opened a pull request that attempts to address it.

I would be very grateful if you could give me the chance to contribute here. If there are any problems with the PR, please feel free to let me know — I’ll be happy to update it accordingly!

[injae-kim]

Fix PR: #46854 PTAL~! 👍

[snicoll]

@injae-kim please refrain from commenting things like that. We already received the previous notification and this just adds noise and sends a notification to 3K+ people.