/*

 * Copyright 2003-2005 Sun Microsystems, Inc.  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.  Sun designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 */

package java.lang.reflect;

import java.lang.annotation.Annotation;

/**

 * Represents an annotated element of the program currently running in this

 * VM.  This interface allows annotations to be read reflectively.  All

 * annotations returned by methods in this interface are immutable and

 * serializable.  It is permissible for the caller to modify the

 * arrays returned by accessors for array-valued enum members; it will

 * have no affect on the arrays returned to other callers.

 *

 * <p>If an annotation returned by a method in this interface contains

 * (directly or indirectly) a {@link Class}-valued member referring to

 * a class that is not accessible in this VM, attempting to read the class

 * by calling the relevant Class-returning method on the returned annotation

 * will result in a {@link TypeNotPresentException}.

 *

 * <p>Similarly, attempting to read an enum-valued member will result in

 * a {@link EnumConstantNotPresentException} if the enum constant in the

 * annotation is no longer present in the enum type.

 *

 * <p>Finally, Attempting to read a member whose definition has evolved

 * incompatibly will result in a {@link

 * java.lang.annotation.AnnotationTypeMismatchException} or an

 * {@link java.lang.annotation.IncompleteAnnotationException}.

 *

 * @since 1.5

 * @author Josh Bloch

 */

public interface AnnotatedElement {

    /**

     * Returns true if an annotation for the specified type

     * is present on this element, else false.  This method

     * is designed primarily for convenient access to marker annotations.

     *

     * @param annotationClass the Class object corresponding to the

     *        annotation type

     * @return true if an annotation for the specified annotation

     *     type is present on this element, else false

     * @throws NullPointerException if the given annotation class is null

     * @since 1.5

     */

     boolean isAnnotationPresent(Class<? extends Annotation> annotationClass);

   /**

     * Returns this element's annotation for the specified type if

     * such an annotation is present, else null.

     *

     * @param annotationClass the Class object corresponding to the

     *        annotation type

     * @return this element's annotation for the specified annotation type if

     *     present on this element, else null

     * @throws NullPointerException if the given annotation class is null

     * @since 1.5

     */

    <T extends Annotation> T getAnnotation(Class<T> annotationClass);

    /**

     * Returns all annotations present on this element.  (Returns an array

     * of length zero if this element has no annotations.)  The caller of

     * this method is free to modify the returned array; it will have no

     * effect on the arrays returned to other callers.

     *

     * @return all annotations present on this element

     * @since 1.5

     */

    Annotation[] getAnnotations();

    /**

     * Returns all annotations that are directly present on this

     * element.  Unlike the other methods in this interface, this method

     * ignores inherited annotations.  (Returns an array of length zero if

     * no annotations are directly present on this element.)  The caller of

     * this method is free to modify the returned array; it will have no

     * effect on the arrays returned to other callers.

     *

     * @return All annotations directly present on this element

     * @since 1.5

     */

    Annotation[] getDeclaredAnnotations();

}