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.commons.io.monitor;
018import java.io.File;
019
020/**
021 * A listener that receives events of file system modifications.
022 * <p>
023 * Register {@link FileAlterationListener}s with a {@link FileAlterationObserver}.
024 *
025 * @see FileAlterationObserver
026 *
027 * @since 2.0
028 */
029public interface FileAlterationListener {
030
031    /**
032     * File system observer started checking event.
033     *
034     * @param observer The file system observer
035     */
036    void onStart(final FileAlterationObserver observer);
037
038    /**
039     * Directory created Event.
040     *
041     * @param directory The directory created
042     */
043    void onDirectoryCreate(final File directory);
044
045    /**
046     * Directory changed Event.
047     *
048     * @param directory The directory changed
049     */
050    void onDirectoryChange(final File directory);
051
052    /**
053     * Directory deleted Event.
054     *
055     * @param directory The directory deleted
056     */
057    void onDirectoryDelete(final File directory);
058
059    /**
060     * File created Event.
061     *
062     * @param file The file created
063     */
064    void onFileCreate(final File file);
065
066    /**
067     * File changed Event.
068     *
069     * @param file The file changed
070     */
071    void onFileChange(final File file);
072
073    /**
074     * File deleted Event.
075     *
076     * @param file The file deleted
077     */
078    void onFileDelete(final File file);
079
080    /**
081     * File system observer finished checking event.
082     *
083     * @param observer The file system observer
084     */
085    void onStop(final FileAlterationObserver observer);
086}