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package javax.lang.model.element;

The nesting kind of a type element. Type elements come in four varieties: top-level, member, local, and anonymous. Nesting kind is a non-standard term used here to denote this classification.

Note that it is possible additional nesting kinds will be added in future versions of the platform.

Example: The classes below are annotated with their nesting kind.

import java.lang.annotation.*;
import static java.lang.annotation.RetentionPolicy.*;
import javax.lang.model.element.*;
import static javax.lang.model.element.NestingKind.*;
@Nesting(TOP_LEVEL)
public class NestingExamples {
    @Nesting(MEMBER)
    static class MemberClass1{}
    @Nesting(MEMBER)
    class MemberClass2{}
    public static void main(String... argv) {
        @Nesting(LOCAL)
        class LocalClass{};
        Class<?>[] classes = {
            NestingExamples.class,
            MemberClass1.class,
            MemberClass2.class,
            LocalClass.class
        };
        for(Class<?> clazz : classes) {
            System.out.format("%s is %s%n",
                              clazz.getName(),
                              clazz.getAnnotation(Nesting.class).value());
        }
    }
}
@Retention(RUNTIME)
@interface Nesting {
    NestingKind value();
}
Author:Joseph D. Darcy, Scott Seligman, Peter von der Ahé
Since:1.6
/** * The <i>nesting kind</i> of a type element. * Type elements come in four varieties: * top-level, member, local, and anonymous. * <i>Nesting kind</i> is a non-standard term used here to denote this * classification. * * <p>Note that it is possible additional nesting kinds will be added * in future versions of the platform. * * <p><b>Example:</b> The classes below are annotated with their nesting kind. * <blockquote><pre> * * import java.lang.annotation.*; * import static java.lang.annotation.RetentionPolicy.*; * import javax.lang.model.element.*; * import static javax.lang.model.element.NestingKind.*; * * &#64;Nesting(TOP_LEVEL) * public class NestingExamples { * &#64;Nesting(MEMBER) * static class MemberClass1{} * * &#64;Nesting(MEMBER) * class MemberClass2{} * * public static void main(String... argv) { * &#64;Nesting(LOCAL) * class LocalClass{}; * * Class&lt;?&gt;[] classes = { * NestingExamples.class, * MemberClass1.class, * MemberClass2.class, * LocalClass.class * }; * * for(Class&lt;?&gt; clazz : classes) { * System.out.format("%s is %s%n", * clazz.getName(), * clazz.getAnnotation(Nesting.class).value()); * } * } * } * * &#64;Retention(RUNTIME) * &#64;interface Nesting { * NestingKind value(); * } * </pre></blockquote> * * @author Joseph D. Darcy * @author Scott Seligman * @author Peter von der Ah&eacute; * @since 1.6 */
public enum NestingKind {
A top-level class or interface, not contained within another class or interface.
/** * A top-level class or interface, not contained within another * class or interface. */
TOP_LEVEL,
A class or interface that is a named member of another class or interface.
@jls8.5 Member Class and Interface Declarations
/** * A class or interface that is a named member of another class or * interface. * @jls 8.5 Member Class and Interface Declarations */
MEMBER,
A named class or interface declared within a construct other than a class or interface.
@jls14.3 Local Class Declarations
/** * A named class or interface declared within a construct other * than a class or interface. * @jls 14.3 Local Class Declarations */
LOCAL,
A class without a name.
@jls15.9.5 Anonymous Class Declarations
/** * A class without a name. * @jls 15.9.5 Anonymous Class Declarations */
ANONYMOUS;
Does this constant correspond to a nested type element? A nested type element is any that is not top-level. More specifically, an inner type element is any nested type element that is not static.
Returns:whether or not the constant is nested
@jls14.3 Local Class Declarations
/** * Does this constant correspond to a nested type element? * A <i>nested</i> type element is any that is not top-level. * More specifically, an <i>inner</i> type element is any nested type element that * is not {@linkplain Modifier#STATIC static}. * @return whether or not the constant is nested * @jls 14.3 Local Class Declarations */
public boolean isNested() { return this != TOP_LEVEL; } }