Checking if an annotation is of a specific type

java reflection annotations instanceof isinstance
Vivin Paliath picture Vivin Paliath · Jul 27, 2010 · Viewed 20.9k times · Source

I am using reflection to see if an annotation that is attached to a property of a class, is of a specific type. Current I am doing:

if("javax.validation.Valid".equals(annotation.annotationType().getName())) {
   ...
}

Which strikes me as a little kludgey because it relies on a string that is a fully-qualified class-name. If the namespace changes in the future, this could cause subtle errors.

I would like to do:

if(Class.forName(annotation.annotationType().getName()).isInstance(
     new javax.validation.Valid()
)) {
   ...
}

But javax.validation.Valid is an abstract class and cannot be instantiated. Is there a way to simulate instanceof (or basically use isInstance) against an interface or an abstract class?

Answer

Affe picture Affe · Jul 28, 2010

Are you just looking for 

if (annotation.annotationType().equals(javax.validation.Valid.class)){}

?

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