- All Known Subinterfaces:
ArrayType
,DeclaredType
,Element
,ErrorType
,ExecutableElement
,ExecutableType
,IntersectionType
,ModuleElement
,NoType
,NullType
,PackageElement
,Parameterizable
,PrimitiveType
,QualifiedNameable
,RecordComponentElement
,ReferenceType
,TypeElement
,TypeMirror
,TypeParameterElement
,TypeVariable
,UnionType
,VariableElement
,WildcardType
In the definitions below, an annotation A has an annotation interface AI. If AI is a repeatable annotation interface, the type of the containing annotation is AIC.
Annotation A is directly present on a construct C if either:
- A is explicitly or implicitly
declared as applying to
the source code representation of C.
Typically, if exactly one annotation of type AI appears in the source code of representation of C, then A is explicitly declared as applying to C. An annotation of type AI on a record component can be implicitly propagated down to affiliated mandated members. Type annotations modifying the type of a record component can be also propagated to mandated members. Propagation of the annotations to mandated members is governed by rules given in the The Java Language Specification (JLS 8.10.1). If there are multiple annotations of type AI present on C, then if AI is repeatable annotation interface, an annotation of type AIC is implicitly declared on C.
- A representation of A appears in the executable output
for C, such as the
RuntimeVisibleAnnotations
(JVMS 4.7.16) orRuntimeVisibleParameterAnnotations
(JVMS 4.7.17) attributes of a class file.
An annotation A is present on a construct C if either:
- A is directly present on C.
- No annotation of type AI is directly present on C, and C is a class and AI is inheritable and A is present on the superclass of C.
- AI is a repeatable annotation interface with a containing annotation interface AIC.
- An annotation of type AIC is directly present on
C and A is an annotation included in the result of
calling the
value
method of the directly present annotation of type AIC.
- A is directly or indirectly present on C.
- No annotation of type AI is directly or indirectly present on C, and C is a class, and AI is inheritable, and A is associated with the superclass of C.
- See Java Language Specification:
-
9.6 Annotation Interfaces
9.6.4.3@Inherited
9.7.4 Where Annotations May Appear
9.7.5 Multiple Annotations of the Same Interface - Since:
- 1.8
-
Method Summary
Modifier and TypeMethodDescription<A extends Annotation>
AgetAnnotation
(Class<A> annotationType) Returns this construct's annotation of the specified type if such an annotation is present, elsenull
.List
<? extends AnnotationMirror> Returns the annotations that are directly present on this construct.<A extends Annotation>
A[]getAnnotationsByType
(Class<A> annotationType) Returns annotations that are associated with this construct.
-
Method Details
-
getAnnotationMirrors
List<? extends AnnotationMirror> getAnnotationMirrors()Returns the annotations that are directly present on this construct.- Returns:
- the annotations directly present on this construct; an empty list if there are none
-
getAnnotation
Returns this construct's annotation of the specified type if such an annotation is present, elsenull
.The annotation returned by this method could contain an element whose value is of type
Class
. This value cannot be returned directly: information necessary to locate and load a class (such as the class loader to use) is not available, and the class might not be loadable at all. Attempting to read aClass
object by invoking the relevant method on the returned annotation will result in aMirroredTypeException
, from which the correspondingTypeMirror
may be extracted. Similarly, attempting to read aClass[]
-valued element will result in aMirroredTypesException
.Note: This method is unlike others in this and related interfaces. It operates on runtime reflective information — representations of annotation interfaces currently loaded into the VM — rather than on the representations defined by and used throughout these interfaces. Consequently, calling methods on the returned annotation object can throw many of the exceptions that can be thrown when calling methods on an annotation object returned by core reflection. This method is intended for callers that are written to operate on a known, fixed set of annotation interfaces.
- Type Parameters:
A
- the annotation interface- Parameters:
annotationType
- theClass
object corresponding to the annotation interface- Returns:
- this construct's annotation of the specified type if
such an annotation is present, else
null
- See Java Language Specification:
-
9.6.1 Annotation Interface Elements
- See Also:
-
getAnnotationsByType
Returns annotations that are associated with this construct. If there are no annotations associated with this construct, the return value is an array of length 0. The order of annotations which are directly or indirectly present on a construct C is computed as if indirectly present annotations on C are directly present on C in place of their container annotation, in the order in which they appear in the value element of the container annotation. The difference between this method andgetAnnotation(Class)
is that this method detects if its argument is a repeatable annotation interface, and if so, attempts to find one or more annotations of that type by "looking through" a container annotation.The annotations returned by this method could contain an element whose value is of type
Class
. This value cannot be returned directly: information necessary to locate and load a class (such as the class loader to use) is not available, and the class might not be loadable at all. Attempting to read aClass
object by invoking the relevant method on the returned annotation will result in aMirroredTypeException
, from which the correspondingTypeMirror
may be extracted. Similarly, attempting to read aClass[]
-valued element will result in aMirroredTypesException
.Note: This method is unlike others in this and related interfaces. It operates on runtime reflective information — representations of annotation interfaces currently loaded into the VM — rather than on the representations defined by and used throughout these interfaces. Consequently, calling methods on the returned annotation object can throw many of the exceptions that can be thrown when calling methods on an annotation object returned by core reflection. This method is intended for callers that are written to operate on a known, fixed set of annotation interfaces.
- Type Parameters:
A
- the annotation interface- Parameters:
annotationType
- theClass
object corresponding to the annotation interface- Returns:
- this construct's annotations for the specified annotation type if present on this construct, else an empty array
- See Java Language Specification:
-
9.6 Annotation Interfaces
9.6.1 Annotation Interface Elements - See Also:
-