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.validation; 018 019import org.apache.wicket.markup.html.form.FormComponent; 020 021/** 022 * Marker interface for validators that will accept a <code>null</code> value. Without implementing 023 * this interface Wicket will never pass <code>null</code> values to 024 * {@link IValidator#validate(IValidatable)}. 025 * <p> 026 * Keep in mind that the {@link FormComponent} must have set the required property to 027 * <code>false</code>, otherwise Wicket will not permit the validator to process the 028 * <code>null</code> value. 029 * 030 * @author Matej Knopp 031 * @param <T> 032 * type of validatable 033 * @since 1.2.6 034 * @see IValidator 035 * @see FormComponent#setRequired(boolean) 036 */ 037public interface INullAcceptingValidator<T> extends IValidator<T> 038{ 039 040}