| /* |
| * Copyright (c) 2003, 2017, 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; |
| |
| /** |
| * The constants of this enumerated type provide a simple classification of the |
| * syntactic locations where annotations may appear in a Java program. These |
| * constants are used in {@link java.lang.annotation.Target Target} |
| * meta-annotations to specify where it is legal to write annotations of a |
| * given type. |
| * |
| * <p>The syntactic locations where annotations may appear are split into |
| * <em>declaration contexts</em> , where annotations apply to declarations, and |
| * <em>type contexts</em> , where annotations apply to types used in |
| * declarations and expressions. |
| * |
| * <p>The constants {@link #ANNOTATION_TYPE}, {@link #CONSTRUCTOR}, {@link |
| * #FIELD}, {@link #LOCAL_VARIABLE}, {@link #METHOD}, {@link #PACKAGE}, {@link |
| * #MODULE}, {@link #PARAMETER}, {@link #TYPE}, and {@link #TYPE_PARAMETER} |
| * correspond to the declaration contexts in JLS 9.6.4.1. |
| * |
| * <p>For example, an annotation whose type is meta-annotated with |
| * {@code @Target(ElementType.FIELD)} may only be written as a modifier for a |
| * field declaration. |
| * |
| * <p>The constant {@link #TYPE_USE} corresponds to the type contexts in JLS |
| * 4.11, as well as to two declaration contexts: type declarations (including |
| * annotation type declarations) and type parameter declarations. |
| * |
| * <p>For example, an annotation whose type is meta-annotated with |
| * {@code @Target(ElementType.TYPE_USE)} may be written on the type of a field |
| * (or within the type of the field, if it is a nested, parameterized, or array |
| * type), and may also appear as a modifier for, say, a class declaration. |
| * |
| * <p>The {@code TYPE_USE} constant includes type declarations and type |
| * parameter declarations as a convenience for designers of type checkers which |
| * give semantics to annotation types. For example, if the annotation type |
| * {@code NonNull} is meta-annotated with |
| * {@code @Target(ElementType.TYPE_USE)}, then {@code @NonNull} |
| * {@code class C {...}} could be treated by a type checker as indicating that |
| * all variables of class {@code C} are non-null, while still allowing |
| * variables of other classes to be non-null or not non-null based on whether |
| * {@code @NonNull} appears at the variable's declaration. |
| * |
| * @author Joshua Bloch |
| * @since 1.5 |
| * @jls 9.6.4.1 @Target |
| * @jls 4.1 The Kinds of Types and Values |
| */ |
| public enum ElementType { |
| /** Class, interface (including annotation type), or enum declaration */ |
| TYPE, |
| |
| /** Field declaration (includes enum constants) */ |
| FIELD, |
| |
| /** Method declaration */ |
| METHOD, |
| |
| /** Formal parameter declaration */ |
| PARAMETER, |
| |
| /** Constructor declaration */ |
| CONSTRUCTOR, |
| |
| /** Local variable declaration */ |
| LOCAL_VARIABLE, |
| |
| /** Annotation type declaration */ |
| ANNOTATION_TYPE, |
| |
| /** Package declaration */ |
| PACKAGE, |
| |
| /** |
| * Type parameter declaration |
| * |
| * @since 1.8 |
| */ |
| TYPE_PARAMETER, |
| |
| /** |
| * Use of a type |
| * |
| * @since 1.8 |
| */ |
| TYPE_USE, |
| |
| /** |
| * Module declaration. |
| * |
| * @since 9 |
| */ |
| MODULE |
| } |