| /* |
| * Copyright (c) 2003, 2020, 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 |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| 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(); |
| } |
