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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
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 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * 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).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
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 *
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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> and <em>present</em> are used
 * throughout this interface to describe precisely which annotations
 * are returned by methods:
 *
 * <p>An annotation <i>A</i> is <em>directly present</em> on a
 * construct <i>E</i> if <i>E</i> is annotated, and:
 *
 * <ul>
 *
 * <li> for an invocation of {@code getAnnotation(Class<T>)} or
 * {@code getAnnotationMirrors()}, <i>E</i>'s annotations contain <i>A</i>.
 *
 * <li> for an invocation of getAnnotationsByType(Class<T>),
 * <i>E</i>'s annotations either contain <i>A</i> or, if the type of
 * <i>A</i> is repeatable, contain exactly one annotation whose value
 * element contains <i>A</i> and whose type is the containing
 * annotation type of <i>A</i>'s type.
 *
 * </ul>
 *
 * <p>An annotation A is <em>present</em> on a construct E if either:
 *
 * <ul>
 *  <li> <i>A</i> is <em>directly present</em> on <i>E</i>; or
 *
 *  <li> <i>A</i> is not <em>directly present</em> on <i>E</i>, and
 *  <i>E</i> is an element representing a class, and <i>A</i>'s type
 *  is inheritable, and <i>A</i> is <em>present</em> on the element
 *  representing the superclass of <i>E</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 &mdash;
     * representations of annotation types currently loaded into the
     * VM &mdash; 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 element's or type use's annotation for the
     * specified annotation type if present on this element, 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>present</em> on this construct.
     *
     * If there are no annotations <em>present</em> on this construct,
     * the return value is an array of length 0.
     *
     * 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 &mdash;
     * representations of annotation types currently loaded into the
     * VM &mdash; 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 element's annotations for the specified annotation
     *         type if present on this element, else an empty array
     *
     * @see #getAnnotationMirrors()
     * @see #getAnnotation(java.lang.Class)
     * @see java.lang.reflect.AnnotatedElement#getAnnotationsByType
     * @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);
}