1 /*
   2  * Copyright (c) 2005, 2017, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package javax.lang.model.element;
  27 
  28 /**
  29  * The <i>nesting kind</i> of a type element.
  30  * Type elements come in four varieties:
  31  * top-level, member, local, and anonymous.
  32  * <i>Nesting kind</i> is a non-standard term used here to denote this
  33  * classification.
  34  *
  35  * <p>Note that it is possible additional nesting kinds will be added
  36  * in future versions of the platform.
  37  *
  38  * <p><b>Example:</b> The classes below are annotated with their nesting kind.
  39  * <blockquote><pre>
  40  *
  41  * import java.lang.annotation.*;
  42  * import static java.lang.annotation.RetentionPolicy.*;
  43  * import javax.lang.model.element.*;
  44  * import static javax.lang.model.element.NestingKind.*;
  45  *
  46  * @Nesting(TOP_LEVEL)
  47  * public class NestingExamples {
  48  *     @Nesting(MEMBER)
  49  *     static class MemberClass1{}
  50  *
  51  *     @Nesting(MEMBER)
  52  *     class MemberClass2{}
  53  *
  54  *     public static void main(String... argv) {
  55  *         @Nesting(LOCAL)
  56  *         class LocalClass{};
  57  *
  58  *         Class&lt;?&gt;[] classes = {
  59  *             NestingExamples.class,
  60  *             MemberClass1.class,
  61  *             MemberClass2.class,
  62  *             LocalClass.class
  63  *         };
  64  *
  65  *         for(Class&lt;?&gt; clazz : classes) {
  66  *             System.out.format("%s is %s%n",
  67  *                               clazz.getName(),
  68  *                               clazz.getAnnotation(Nesting.class).value());
  69  *         }
  70  *     }
  71  * }
  72  *
  73  * @Retention(RUNTIME)
  74  * @interface Nesting {
  75  *     NestingKind value();
  76  * }
  77  * </pre></blockquote>
  78  *
  79  * @author Joseph D. Darcy
  80  * @author Scott Seligman
  81  * @author Peter von der Ah&eacute;
  82  * @since 1.6
  83  */
  84 public enum NestingKind {
  85     /**
  86      * A top-level type, not contained within another type.
  87      */
  88     TOP_LEVEL,
  89 
  90     /**
  91      * A type that is a named member of another type.
  92      * @jls 8.5 Member Type Declarations
  93      */
  94     MEMBER,
  95 
  96     /**
  97      * A named type declared within a construct other than a type.
  98      * @jls 14.3 Local Class Declarations
  99      */
 100     LOCAL,
 101 
 102     /**
 103      * A type without a name.
 104      * @jls 15.9.5 Anonymous Class Declarations
 105      */
 106     ANONYMOUS;
 107 
 108     /**
 109      * Does this constant correspond to a nested type element?
 110      * A <i>nested</i> type element is any that is not top-level.
 111      * More specifically, an <i>inner</i> type element is any nested type element that
 112      * is not {@linkplain Modifier#STATIC static}.
 113      * @return whether or not the constant is nested
 114      * @jls 14.3 Local Class Declarations
 115      */
 116     public boolean isNested() {
 117         return this != TOP_LEVEL;
 118     }
 119 }