Why does the definition of MyAnnotation need Documented, Inherited, Retention & RetentionPolicy?

Question

What is the purpose of these java.lang.annotation imports in this code? Why are they needed to define MyAnnotation?

import java.lang.annotation.Documented;
import java.lang.annotation.Inherited;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;

@Documented
@Retention(RetentionPolicy.RUNTIME)
@Inherited
public @interface MyAnnotation {
  String value() default "";
}

Look http://stackoverflow.com/a/20432882/715269 for explanation of Documented and Inherited. — Gangnus, Dec 06 '13 at 20:26

score 1 · Accepted Answer · answered Apr 01 '10 at 10:29

1

@Documented and @Inherited are not required. @Retention(RetentionPolicy.RUNTIME) is only needed if you want to process the annotations in the runtime.

answered Apr 01 '10 at 10:29

lexicore

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Why does the definition of MyAnnotation need Documented, Inherited, Retention & RetentionPolicy?

1 Answers1