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 * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * 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
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * 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,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 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.*;

/**
 * Represent a construct that can have annotations.
 *
 * When annotations are on an {@linkplain Element element},
 * they are on a <em>declaration</em>.  When annotations are on a {@linkplain
 * TypeMirror type}, they are on a <em>use</em> of a type.
 *
 * @since 1.8
 */
public interface AnnotatedConstruct {
    /**
     * Returns the annotations that are directly present on this
     * element or type use.
     *
     * @return the annotations directly present on this element or type use;
     *          an empty list if there are none
     */
    List<? extends AnnotationMirror> getAnnotationMirrors();

    /**
     * Returns this element's or type use's annotation for the
     * specified type if such an annotation is present, else {@code
     * null}.  The annotation may be either inherited or directly
     * present on this element.
     *
     * <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
     */
    <A extends Annotation> A getAnnotation(Class<A> annotationType);

    /**
     * Returns annotations that are <em>present</em> on this element or type use.
     *
     * If there are no annotations <em>present</em> on this element or type use,
     * 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> (JLS 9.6), 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
     */
    <A extends Annotation> A[] getAnnotationsByType(Class<A> annotationType);
}