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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
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*
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
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* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
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package javax.lang.model;
import java.lang.annotation.*;
import java.util.List;
import javax.lang.model.element.*;
import javax.lang.model.type.*;
/**
* Represents a construct that can be annotated.
*
* A construct is either an {@linkplain
* javax.lang.model.element.Element element} or a {@linkplain
* javax.lang.model.type.TypeMirror type}. Annotations on an element
* are on a <em>declaration</em>, whereas annotations on a type are on
* a specific <em>use</em> of a type name.
*
* The terms <em>directly present</em>, <em>present</em>,
* <em>indirectly present</em>, and <em>associated </em> are used
* throughout this interface to describe precisely which annotations
* are returned by the methods defined herein.
*
* <p>In the definitions below, an annotation <i>A</i> has an
* annotation type <i>AT</i>. If <i>AT</i> is a repeatable annotation
* type, the type of the containing annotation is <i>ATC</i>.
*
* <p>Annotation <i>A</i> is <em>directly present</em> on a construct
* <i>C</i> if either:
*
* <ul>
*
* <li><i>A</i> is explicitly or implicitly declared as applying to
* the source code representation of <i>C</i>.
*
* <p>Typically, if exactly one annotation of type <i>AT</i> appears in
* the source code of representation of <i>C</i>, then <i>A</i> is
* explicitly declared as applying to <i>C</i>.
*
* If there are multiple annotations of type <i>AT</i> present on
* <i>C</i>, then if <i>AT</i> is repeatable annotation type, an
* annotation of type <i>ATC</i> is implicitly declared on <i>C</i>.
*
* <li> A representation of <i>A</i> appears in the executable output
* for <i>C</i>, such as the {@code RuntimeVisibleAnnotations} or
* {@code RuntimeVisibleParameterAnnotations} attributes of a class
* file.
*
* </ul>
*
* <p>An annotation <i>A</i> is <em>present</em> on a
* construct <i>C</i> if either:
* <ul>
*
* <li><i>A</i> is directly present on <i>C</i>.
*
* <li>No annotation of type <i>AT</i> is directly present on
* <i>C</i>, and <i>C</i> is a class and <i>AT</i> is inheritable
* and <i>A</i> is present on the superclass of <i>C</i>.
*
* </ul>
*
* An annotation <i>A</i> is <em>indirectly present</em> on a construct
* <i>C</i> if both:
*
* <ul>
*
* <li><i>AT</i> is a repeatable annotation type with a containing
* annotation type <i>ATC</i>.
*
* <li>An annotation of type <i>ATC</i> is directly present on
* <i>C</i> and <i>A</i> is an annotation included in the result of
* calling the {@code value} method of the directly present annotation
* of type <i>ATC</i>.
*
* </ul>
*
* An annotation <i>A</i> is <em>associated</em> with a construct
* <i>C</i> if either:
*
* <ul>
*
* <li> <i>A</i> is directly or indirectly present on <i>C</i>.
*
* <li> No annotation of type <i>AT</i> is directly or indirectly
* present on <i>C</i>, and <i>C</i> is a class, and <i>AT</i> is
* inheritable, and <i>A</i> is associated with the superclass of
* <i>C</i>.
*
* </ul>
*
* @since 1.8
* @jls 9.6 Annotation Types
* @jls 9.6.3.3 @Inherited
*/
public interface AnnotatedConstruct {
/**
* Returns the annotations that are <em>directly present</em> on
* this construct.
*
* @return the annotations <em>directly present</em> on this
* construct; an empty list if there are none
*/
List<? extends AnnotationMirror> getAnnotationMirrors();
/**
* Returns this construct's annotation of the specified type if
* such an annotation is <em>present</em>, else {@code null}.
*
* <p> The annotation returned by this method could contain an element
* whose value is of type {@code 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 {@code Class} object by invoking the relevant
* method on the returned annotation
* will result in a {@link MirroredTypeException},
* from which the corresponding {@link TypeMirror} may be extracted.
* Similarly, attempting to read a {@code Class[]}-valued element
* will result in a {@link MirroredTypesException}.
*
* <blockquote>
* <i>Note:</i> 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.
* </blockquote>
*
* @param <A> the annotation type
* @param annotationType the {@code Class} object corresponding to
* the annotation type
* @return this construct's annotation for the specified
* annotation type if present, else {@code null}
*
* @see #getAnnotationMirrors()
* @see java.lang.reflect.AnnotatedElement#getAnnotation
* @see EnumConstantNotPresentException
* @see AnnotationTypeMismatchException
* @see IncompleteAnnotationException
* @see MirroredTypeException
* @see MirroredTypesException
* @jls 9.6.1 Annotation Type Elements
*/
<A extends Annotation> A getAnnotation(Class<A> annotationType);
/**
* Returns annotations that are <em>associated</em> 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 <i>C</i> is computed as if indirectly present
* annotations on <i>C</i> are directly present on <i>C</i> 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 and {@link #getAnnotation(Class)}
* is that this method detects if its argument is a <em>repeatable
* annotation type</em>, and if so, attempts to find one or more
* annotations of that type by "looking through" a container annotation.
*
* <p> The annotations returned by this method could contain an element
* whose value is of type {@code 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 {@code Class} object by invoking the relevant
* method on the returned annotation
* will result in a {@link MirroredTypeException},
* from which the corresponding {@link TypeMirror} may be extracted.
* Similarly, attempting to read a {@code Class[]}-valued element
* will result in a {@link MirroredTypesException}.
*
* <blockquote>
* <i>Note:</i> 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.
* </blockquote>
*
* @param <A> the annotation type
* @param annotationType the {@code Class} object corresponding to
* the annotation type
* @return this construct's annotations for the specified annotation
* type if present on this construct, else an empty array
*
* @see #getAnnotationMirrors()
* @see #getAnnotation(Class)
* @see java.lang.reflect.AnnotatedElement#getAnnotationsByType(Class)
* @see EnumConstantNotPresentException
* @see AnnotationTypeMismatchException
* @see IncompleteAnnotationException
* @see MirroredTypeException
* @see MirroredTypesException
* @jls 9.6 Annotation Types
* @jls 9.6.1 Annotation Type Elements
*/
<A extends Annotation> A[] getAnnotationsByType(Class<A> annotationType);
}