/*

 * Copyright (c) 2003, 2015, 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 java.lang.annotation;

/**

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

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

 * applicable are specified in 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 type

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

 * modifier for any declaration except a type parameter 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 9.7.4.

 *

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

 * declared type is itself a meta-annotation type.  It can only be used on

 * annotation type declarations:

 * <pre>

 *    @Target(ElementType.ANNOTATION_TYPE)

 *    public @interface MetaAnnotationType {

 *        ...

 *    }

 * </pre>

 *

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

 * intended solely for use as a member type in complex annotation type

 * declarations.  It cannot be used to annotate anything directly:

 * <pre>

 *    @Target({})

 *    public @interface MemberType {

 *        ...

 *    }

 * </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 Type

 */

@Documented

@Retention(RetentionPolicy.RUNTIME)

@Target(ElementType.ANNOTATION_TYPE)

public @interface Target {

    /**

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

     * can be applied to.

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

     * can be applied to

     */

    ElementType[] value();

}