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 import java.lang.annotation.Documented; 021 import java.lang.annotation.ElementType; 022 import java.lang.annotation.Retention; 023 import java.lang.annotation.RetentionPolicy; 024 import java.lang.annotation.Target; 025 026 /** 027 * Meta annotation to mark an annotation as a validation constraint. This annotation must specify a 028 * {@link ConstraintValidator} implementation class that has a default constructor. 029 * 030 * @since 2.1 031 */ 032 @Documented 033 @Target(ElementType.ANNOTATION_TYPE) 034 @Retention(RetentionPolicy.RUNTIME) 035 public @interface Constraint { 036 037 /** 038 * {@link ConstraintValidator} class that implements the validation logic for the annotated constraint annotation. 039 */ 040 Class<? extends ConstraintValidator<? extends Annotation>> value(); 041 }