Java Type Use annotation - How to read them

Question

I'm using custom type use annotation. I can't read them from an object like any other regular annotation:

public class TestingAnnotations {



public static void main(final String[] args) {
     final @CustomAnnotation TypeAnnotated b = new @CustomAnnotation TypeAnnotated();
     System.out.println(b.getClass().getAnnotation(CustomAnnotation.class)); //<-- prints null :(
   }
}

@Target({ElementType.TYPE_USE, ElementType.TYPE})
@Retention(RetentionPolicy.RUNTIME)
@interface CustomAnnotation {

}

class TypeAnnotated {

}

So, how can I check b instance is annotated?

Thanks

Looks like you can't with a local variable: https://stackoverflow.com/questions/17237813 — Jorn Vernee, Jun 23 '17 at 14:59

score 0 · Accepted Answer · answered Jun 23 '17 at 15:09

0

you are actually not annotating the class.... a class is annotated when it looks like:

@CustomAnnotation
class TypeAnnotated {

}

after that you will get the annotation doing:

TypeAnnotated b = new TypeAnnotated();
System.out.println(b.getClass().getAnnotation(CustomAnnotation.class));

answered Jun 23 '17 at 15:09

ΦXocę 웃 Пepeúpa ツ

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Yes, my intention is not to annotate the class but the object/instance – Rodrigo Silva Jun 23 '17 at 15:23

score 0 · Answer 2 · answered Feb 04 '22 at 04:19

0

It looks like you actually want a local variabel annotation

@Target({ElementType.TYPE_USE, ElementType.LOCAL_VARIABLE})
public @interface CustomAnnotation {
}

Then this compiles just fine:

answered Feb 04 '22 at 04:19

Ghoti and Chips

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Java Type Use annotation - How to read them

2 Answers2