How to get the annotation on constructor value parameter?

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1

Hi, I am working on annotation processor. I try to get the annotations that data class constructor parameter has (example see slug has @Input(Parameter::class)). But I cannot find the way to do it.

I have data class and annotations:

@Retention(AnnotationRetention.RUNTIME) // try this with .SOURCE also
@Target(AnnotationTarget.VALUE_PARAMETER)
annotation class GqlInput (
    val input: KClass<*>
)

@Query("Query")
@Response
data class Response(
    val id: Int,
    val title: String,
    val label: String,
    val images: List<String>,
    @Input(Parameter::class)
    val slug: Slug
)

I am able to loop through the constructor parameter using kotlinpoet-metadata (which is extended version of kotlinx-metadata-jvm) by this way:

val parentMetadata = (element as TypeElement).toImmutableKmClass()

parentMetadata.constructors[0].valueParameters.map { prop ->

   // this will loop through class properties and return ImmutableKmValueParameter
   // eg: id, title, label, images, slug.

   // then, I need to get the annotation that property has here.
   // eg: @Input(Parameter::class) on slug property.

   // if prop is slug, this will return true.
   val isAnnotationAvailable = prop.hasAnnotations

   // Here I need to get the annotated value
   // val annotation = [..something..].getAnnotation(Input::class)
   // How to get the annotation? So I can do this:
   if ([prop annotation] has [@Input]) {
      do the something.
   }
}

I was post this on stackoverflow, but there’s no kotlinx-metadata tag (not enough point to create new tag). So I’ll also post this here. If you want to answer on stackoverflow: Getting annotation from constructor value parameter using kotlinpoet-metadata - Stack Overflow

Thanks in advance