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 */
017package org.apache.wicket.bean.validation;
018
019import java.lang.annotation.Annotation;
020
021import javax.validation.constraints.Size;
022
023import org.apache.wicket.markup.ComponentTag;
024import org.apache.wicket.markup.html.form.FormComponent;
025
026/**
027 * An object that can modify a component's markup tag during render based on values of a constraint
028 * annotation. An example would be a modifier that adds the {@code maxlen} attribute to the tag
029 * given a {@link Size} annotation.
030 * 
031 * @author igor
032 * 
033 */
034@FunctionalInterface
035public interface ITagModifier<T extends Annotation>
036{
037        /**
038         * Modify the tag
039         * 
040         * @param component
041         *            component the tag belongs to
042         * @param tag
043         *            markup tag to be modified
044         * @param annotation
045         *            constraint annotation
046         */
047        void modify(FormComponent<?> component, ComponentTag tag, T annotation);
048        
049        ITagModifier<?> NO_OP = (component, tag, annotation) -> {
050        };
051}