Annotation Type Target
@Documented @Retention(RUNTIME) @Target(ANNOTATION_TYPE) public @interface Target
Indicates the contexts in which an annotation type is applicable. The declaration contexts and type contexts in which an annotation type may be applicable are specified in JLS 9.6.4.1, and denoted in source code by enum constants of java.lang.annotation.ElementType
.
If an @Target
meta-annotation is not present on an annotation type T
, then an annotation of type T
may be written as a modifier for any declaration except a type parameter declaration.
If an @Target
meta-annotation is present, the compiler will enforce the usage restrictions indicated by ElementType
enum constants, in line with JLS 9.7.4.
For example, this @Target
meta-annotation indicates that the declared type is itself a meta-annotation type. It can only be used on annotation type declarations:
@Target(ElementType.ANNOTATION_TYPE) public @interface MetaAnnotationType { ... }
This @Target
meta-annotation indicates that the declared type is intended solely for use as a member type in complex annotation type declarations. It cannot be used to annotate anything directly:
@Target({}) public @interface MemberType { ... }
It is a compile-time error for a single ElementType
constant to appear more than once in an @Target
annotation. For example, the following @Target
meta-annotation is illegal:
@Target({ElementType.FIELD, ElementType.METHOD, ElementType.FIELD}) public @interface Bogus { ... }
- Since:
- 1.5
Required Element Summary
Modifier and Type | Required Element | Description |
---|---|---|
ElementType[] | value | Returns an array of the kinds of elements an annotation type can be applied to. |
Element Detail
value
ElementType[] value
Returns an array of the kinds of elements an annotation type can be applied to.
- Returns:
- an array of the kinds of elements an annotation type can be applied to