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package java.lang.annotation;
/**
* The constants of this enumerated class 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 interface 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: class and interface
* declarations (including annotation declarations) and type parameter
* declarations.
* {@code @Target(ElementType.TYPE_USE)} may be written on the class or
* interface of a field (or within the class or interface of the field, if it
* is a nested or parameterized class or interface, or array class), and may
* also appear as a modifier for, say, a class declaration.
* <p>The {@code TYPE_USE} constant includes class and interface declarations
* and type parameter declarations as a convenience for designers of
* type checkers which give semantics to annotation interfaces. For example,
* if the annotation interface {@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 interface), enum, or record
* declaration */
TYPE,
/** Field declaration (includes enum constants) */
FIELD,
/** Method declaration */
METHOD,
/** Formal parameter declaration */
PARAMETER,
/** Constructor declaration */
CONSTRUCTOR,
/** Local variable declaration */
LOCAL_VARIABLE,
/** Annotation interface declaration (Formerly known as an annotation type.) */
ANNOTATION_TYPE,
/** Package declaration */
PACKAGE,
* Type parameter declaration
* @since 1.8
TYPE_PARAMETER,
* Use of a type
TYPE_USE,
* Module declaration.
* @since 9
MODULE,
* Record component
* @jls 8.10.3 Record Members
* @jls 9.7.4 Where Annotations May Appear
* @since 16
RECORD_COMPONENT;
}