    001    /*
    002     * Licensed to the Apache Software Foundation (ASF) under one or more
    003     * contributor license agreements. See the NOTICE file distributed with
    004     * this work for additional information regarding copyright ownership.
    005     * The ASF licenses this file to You under the Apache license, Version 2.0
    006     * (the "License"); you may not use this file except in compliance with
    007     * the License. You may obtain a copy of the License at
    008     *
    009     *      http://www.apache.org/licenses/LICENSE-2.0
    010     *
    011     * Unless required by applicable law or agreed to in writing, software
    012     * distributed under the License is distributed on an "AS IS" BASIS,
    013     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    014     * See the license for the specific language governing permissions and
    015     * limitations under the license.
    016     */
    017    package org.apache.logging.log4j.core.config.plugins.validation;
    018
    019    import java.lang.annotation.Annotation;
    020
    021    /**
    022     * Interface that {@link Constraint} annotations must implement to perform validation logic.
    023     *
    024     * @param <A> the {@link Constraint} annotation this interface validates.
    025     * @since 2.1
    026     */
    027    public interface ConstraintValidator<A extends Annotation> {
    028
    029        /**
    030         * Called before this validator is used with the constraint annotation value.
    031         *
    032         * @param annotation the annotation value this validator will be validating.
    033         */
    034        void initialize(A annotation);
    035
    036        /**
    037         * Indicates if the given value is valid.
    038         *
    039         * @param value the value to validate.
    040         * @return {@code true} if the given value is valid.
    041         */
    042        boolean isValid(Object value);
    043    }