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.logging.log4j.core.util;
018
019import java.io.File;
020
021/**
022 * Watches for changes in a {@link File} and performs an action when the file is modified.
023 *
024 * @see WatchManager
025 */
026public interface FileWatcher {
027
028    /**
029     * Called when a {@link WatchManager} detects that the given {@link File} changed.
030     *
031     * @param file
032     *            the file that changed.
033     * @see WatchManager
034     */
035    void fileModified(File file);
036}