Documented in Java

java.lang.annotation.Documented

If the annotation @Documented is present on the declaration of an annotation type A, then any @A annotation on an element is considered part of the element's public contract.

In more detail, when an annotation type A is annotated with Documented, the presence and value of annotations of type A are a part of the public contract of the elements Aannotates. Conversely, if an annotation type B is not annotated with Documented, the presence and value of B annotations are not part of the public contract of the elements B annotates.

Concretely, if an annotation type is annotated with Documented, by default a tool like javadoc will display annotations of that type in its output while annotations of annotation types without Documented will not be displayed.

Declaration


@Documented
@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.ANNOTATION_TYPE)
public @interface Documented {
}



Some other classes/interfaces of java.lang.annotation

Native: Indicates that a field defining a constant value may be referenced from native code.

InheritedIndicates that an annotation type is automatically inherited.

IncompleteAnnotationExceptionThrown to indicate that a program has attempted to access an element of an annotation type that was added to the annotation type definition after the annotation was compiled (or serialized). 

AnnotationFormatErrorThrown when the annotation parser attempts to read an annotation from a class file and determines that the annotation is malformed.

ElementTypeThe constants of this enumerated type provide a simple classification of the syntactic locations where annotations may appear in a Java program.

DocumentedIf the annotation @Documented is present on the declaration of an annotation type A, then any @A annotation on an element is considered part of the element's public contract.

AnnotationTypeMismatchExceptionThrown to indicate that a program has attempted to access an element of an annotation whose type has changed after the annotation was compiled.

AnnotationThe common interface is extended by all annotation types.

RepeatableThe annotation type is java.lang.annotation.Repeatable is used to indicate that the annotation type whose declaration it(meta-)annotates is repeatable.

RetentionIndicates how long annotations with the annotated type are to be retained. If no Retention annotation is present on an annotation-type declaration, the retention policy defaults to RetentionPolicy.CLASS.

RetentionPolicyAnnotation retention policy. The constants of this enumerated type describe the various policies for retaining annotations.

TargetIndicates the contexts in which an annotation type is applicable.

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