src/java.compiler/share/classes/javax/lang/model/element/ElementKind.java

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package javax.lang.model.element;

/**
 * The {@code kind} of an element.
 *
 * <p>Note that it is possible additional element kinds will be added
 * to accommodate new, currently unknown, language structures added to
 * future versions of the Java programming language.
 *
 * @see Element
 * @since 1.6
 */
public enum ElementKind {

    /** A package. */
    PACKAGE,

    // Declared types
    /** An enum class. */
    ENUM,
    /**
     * A class not described by a more specific kind (like {@code
     * ENUM} or {@code RECORD}).
     */
    CLASS,

    /** An annotation interface. (Formerly known as an annotation type.) */
    ANNOTATION_TYPE,
    /**
     * An interface not described by a more specific kind (like
     * {@code ANNOTATION_TYPE}).
     */
    INTERFACE,

    // Variables
    /** An enum constant. */
    ENUM_CONSTANT,
    /**
     * A field not described by a more specific kind (like
     * {@code ENUM_CONSTANT}).
     */
    FIELD,
    /** A parameter of a method or constructor. */
    PARAMETER,
    /** A local variable. */
    LOCAL_VARIABLE,
    /** A parameter of an exception handler. */
    EXCEPTION_PARAMETER,

    // Executables
    /** A method. */
    METHOD,
    /** A constructor. */
    CONSTRUCTOR,
    /** A static initializer. */
    STATIC_INIT,
    /** An instance initializer. */
    INSTANCE_INIT,

    /** A type parameter. */
    TYPE_PARAMETER,

    /**
     * An implementation-reserved element.  This is not the element
     * you are looking for.
     */
    OTHER,

    // Constants added since initial release

    /**
     * A resource variable.
     * @since 1.7
     */
     RESOURCE_VARIABLE,

    /**
     * A module.
     * @since 9
     */
     MODULE,

    /**
     * A record class.
     * @since 16
     */
    RECORD,

    /**
     * A record component of a {@code record}.
     * @since 16
     */
    RECORD_COMPONENT,

    /**
     * A binding variable in a pattern.
     * @since 16
     */
    BINDING_VARIABLE;

    // Maintenance note: check if the default implementation of
    // Elements.getOutermostTypeElement needs updating when new kind
    // constants are added.

    /**
     * Returns {@code true} if this is a kind of class:
     * either {@code CLASS} or {@code ENUM} or {@code RECORD}.
     *
     * @return {@code true} if this is a kind of class
     */
    public boolean isClass() {
        return this == CLASS || this == ENUM || this == RECORD;
    }

    /**
     * Returns {@code true} if this is a kind of interface:
     * either {@code INTERFACE} or {@code ANNOTATION_TYPE}.
     *
     * @return {@code true} if this is a kind of interface
     */
    public boolean isInterface() {
        return this == INTERFACE || this == ANNOTATION_TYPE;
    }

    /**
     * {@return {@code true} if this is a kind of declared type, a
     * {@linkplain #isClass() class} or an {@linkplain #isInterface()
     * interface}, and {@code false} otherwise}
     *
     * @since 19
     */
    public boolean isDeclaredType() {
        return isClass() || isInterface();
    }

    /**
     * Returns {@code true} if this is a kind of field:
     * either {@code FIELD} or {@code ENUM_CONSTANT}.
     *
     * @return {@code true} if this is a kind of field
     */
    public boolean isField() {
        return this == FIELD || this == ENUM_CONSTANT;
    }

    /**
     * Returns {@code true} if this is a kind of executable: either
     * {@code METHOD} or {@code CONSTRUCTOR} or {@code STATIC_INIT} or
     * {@code INSTANCE_INIT}.
     *
     * @return {@code true} if this is a kind of executable
     * @since 19
     */
    public boolean isExecutable() {
        return switch(this) {
        case METHOD, CONSTRUCTOR, STATIC_INIT, INSTANCE_INIT -> true;
        default -> false;
        };
    }

    /**
     * Returns {@code true} if this is a kind of initializer: either
     * {@code STATIC_INIT} or {@code INSTANCE_INIT}.
     *
     * @return {@code true} if this is a kind of initializer
     * @since 19
     */
    public boolean isInitializer() {
        return switch(this) {
        case STATIC_INIT, INSTANCE_INIT -> true;
        default -> false;
        };
    }
    /**
     * Returns {@code true} if this is a kind of variable: including
     * {@code ENUM_CONSTANT}, {@code FIELD}, {@code PARAMETER},
     * {@code LOCAL_VARIABLE}, {@code EXCEPTION_PARAMETER},
     * {@code RESOURCE_VARIABLE}, and {@code BINDING_VARIABLE}.
     *
     * @return {@code true} if this is a kind of variable
     * @since 19
     */
    public boolean isVariable() {
        return switch(this) {
        case ENUM_CONSTANT, FIELD, PARAMETER,
             LOCAL_VARIABLE, EXCEPTION_PARAMETER, RESOURCE_VARIABLE,
             BINDING_VARIABLE -> true;
        default -> false;
        };
    }
}