javax.lang.model

Interface AnnotatedConstruct

All Known Subinterfaces:

ArrayType, DeclaredType, Element, ErrorType, ExecutableElement, ExecutableType, IntersectionType, NoType, NullType, PackageElement, Parameterizable, PrimitiveType, QualifiedNameable, ReferenceType, TypeElement, TypeMirror, TypeParameterElement, TypeVariable, UnionType, VariableElement, WildcardType

public interface AnnotatedConstruct

Represents a construct that can be annotated. A construct is either an element or a type. Annotations on an element are on a declaration, whereas annotations on a type are on a specific use of a type name. The terms directly present and present are used throughout this interface to describe precisely which annotations are returned by methods:

An annotation A is directly present on a construct E if E is annotated, and:

• for an invocation of getAnnotation(Class<T>) or getAnnotationMirrors(), E's annotations contain A.
• for an invocation of getAnnotationsByType(Class), E's annotations either contain A or, if the type of A is repeatable, contain exactly one annotation whose value element contains A and whose type is the containing annotation type of A's type.

An annotation A is present on a construct E if either:

• A is directly present on E; or
• A is not directly present on E, and E is an element representing a class, and A's type is inheritable, and A is present on the element representing the superclass of E.

Since:

1.8

Method Summary

Methods

Modifier and Type	Method and Description
<A extends Annotation> A	getAnnotation(Class<A> annotationType) Returns this construct's annotation of the specified type if such an annotation is present, else null.
List<? extends AnnotationMirror>	getAnnotationMirrors() Returns the annotations that are directly present on this construct.
<A extends Annotation> A[]	getAnnotationsByType(Class<A> annotationType) Returns annotations that are present on this construct.

Method Detail

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

<A extends Annotation> A getAnnotation(Class<A> annotationType)

Returns this construct's annotation of the specified type if such an annotation is present, else null.

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 a Class object by invoking the relevant method on the returned annotation will result in a MirroredTypeException, from which the corresponding TypeMirror may be extracted. Similarly, attempting to read a Class[]-valued element will result in a MirroredTypesException.

Note: This method is unlike others in this and related interfaces. It operates on runtime reflective information — representations of annotation types 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 types.

Type Parameters:

A - the annotation type

Parameters:

annotationType - the Class object corresponding to the annotation type

Returns:

this element's or type use's annotation for the specified annotation type if present on this element, else null

See Also:

getAnnotationMirrors(), AnnotatedElement.getAnnotation(java.lang.Class<T>), EnumConstantNotPresentException, AnnotationTypeMismatchException, IncompleteAnnotationException, MirroredTypeException, MirroredTypesException

getAnnotationsByType

<A extends Annotation> A[] getAnnotationsByType(Class<A> annotationType)

Returns annotations that are present on this construct. If there are no annotations present on this construct, the return value is an array of length 0. The difference between this method and getAnnotation(Class) is that this method detects if its argument is a repeatable annotation type, 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 a Class object by invoking the relevant method on the returned annotation will result in a MirroredTypeException, from which the corresponding TypeMirror may be extracted. Similarly, attempting to read a Class[]-valued element will result in a MirroredTypesException.

Note: This method is unlike others in this and related interfaces. It operates on runtime reflective information — representations of annotation types 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 types.

Type Parameters:

A - the annotation type

Parameters:

annotationType - the Class object corresponding to the annotation type

Returns:

this element's annotations for the specified annotation type if present on this element, else an empty array

See Also:

getAnnotationMirrors(), getAnnotation(java.lang.Class), java.lang.reflect.AnnotatedElement#getAnnotationsByType, EnumConstantNotPresentException, AnnotationTypeMismatchException, IncompleteAnnotationException, MirroredTypeException, MirroredTypesException