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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

 * 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 java.lang.annotation;

/**

 * Indicates the contexts in which an annotation interface is applicable. The

 * declaration contexts and type contexts in which an annotation interface may

 * be applicable are specified in JLS {@jls 9.6.4.1}, and denoted in source code by

 * enum constants of {@link ElementType java.lang.annotation.ElementType}.

 *

 * <p>If an {@code @Target} meta-annotation is not present on an annotation

 * interface {@code T}, then an annotation of type {@code T} may be written as

 * a modifier for any declaration.

 *

 * <p>If an {@code @Target} meta-annotation is present, the compiler will enforce

 * the usage restrictions indicated by {@code ElementType}

 * enum constants, in line with JLS {@jls 9.7.4}.

 *

 * <p>For example, this {@code @Target} meta-annotation indicates that the

 * declared interface is itself a meta-annotation interface.  It can only be

 * used on annotation interface declarations:

 * <pre>

 *    @Target(ElementType.ANNOTATION_TYPE)

 *    public @interface MetaAnnotationType {

 *        ...

 *    }

 * </pre>

 *

 * <p>This {@code @Target} meta-annotation indicates that the declared class or

 * interface is intended solely for use as a member class or interface in

 * complex annotation interface declarations.  It cannot be used to annotate

 * anything directly:

 * <pre>

 *    @Target({})

 *    public @interface MemberInterface {

 *        ...

 *    }

 * </pre>

 *

 * <p>It is a compile-time error for a single {@code ElementType} constant to

 * appear more than once in an {@code @Target} annotation.  For example, the

 * following {@code @Target} meta-annotation is illegal:

 * <pre>

 *    @Target({ElementType.FIELD, ElementType.METHOD, ElementType.FIELD})

 *    public @interface Bogus {

 *        ...

 *    }

 * </pre>

 *

 * @since 1.5

 * @jls 9.6.4.1 @Target

 * @jls 9.7.4 Where Annotations May Appear

 * @jls 9.7.5 Multiple Annotations of the Same Interface

 */

@Documented

@Retention(RetentionPolicy.RUNTIME)

@Target(ElementType.ANNOTATION_TYPE)

public @interface Target {

    /**

     * Returns an array of the kinds of elements an annotation interface

     * can be applied to.

     * @return an array of the kinds of elements an annotation interface

     * can be applied to

     */

    ElementType[] value();

}