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.util;
018
019/**
020 * Represents an object that is a part of a hierarchy
021 * 
022 * @author Igor Vaynberg (ivaynberg)
023 * @param <T>
024 */
025@FunctionalInterface
026public interface IHierarchical<T>
027{
028        /**
029         * @return object's parent or {@code null} if this object is the root of the hierarchy
030         */
031        T getParent();
032}