ContainedBy.java

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package java.lang.annotation;

/**
 * The annotation type {@code java.lang.annotation.ContainedBy} is
 * used to indicate that the annotation type whose declaration it
 * (meta-)annotates is <em>repeatable</em>. The value of
 * {@code @ContainedBy} indicates the <em>containing annotation
 * type</em> for the repeatable annotation type.
 *
 * <p>The pair of annotation types {@code @ContainedBy} and
 * {@link java.lang.annotation.ContainerFor @ContainerFor} are used to
 * indicate that annotation types are repeatable. Specifically:
 *
 * <ul>
 * <li>The annotation type {@code @ContainedBy} is used on the
 * declaration of a repeatable annotation type (JLS 9.6) to indicate
 * its containing annotation type.
 *
 * <li>The annotation type {@code @ContainerFor} is used on the
 * declaration of a containing annotation type (JLS 9.6) to indicate
 * the repeatable annotation type for which it serves as the
 * containing annotation type.
 * </ul>
 *
 * <p>
 * An inconsistent pair of {@code @ContainedBy} and
 * {@code @ContainerFor} annotations on a repeatable annotation type
 * and its containing annotation type (JLS 9.6) will lead to
 * compile-time errors and runtime exceptions when using reflection to
 * read annotations of a repeatable type.
 *
 * @see java.lang.annotation.ContainerFor
 * @since 1.8
 * @jls 9.6 Annotation Types
 * @jls 9.7 Annotations
 */
@Documented
@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.ANNOTATION_TYPE)
public @interface ContainedBy {
    /**
     * Indicates the <em>containing annotation type</em> for the
     * repeatable annotation type.
     */
    Class<? extends Annotation> value();
}