1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one or more 3 * contributor license agreements. See the NOTICE file distributed with 4 * this work for additional information regarding copyright ownership. 5 * The ASF licenses this file to You under the Apache License, Version 2.0 6 * (the "License"); you may not use this file except in compliance with 7 * the License. You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the License for the specific language governing permissions and 15 * limitations under the License. 16 */ 17 package org.apache.commons.io; 18 19 import java.io.File; 20 21 /** 22 * Keeps track of files awaiting deletion, and deletes them when an associated 23 * marker object is reclaimed by the garbage collector. 24 * <p> 25 * This utility creates a background thread to handle file deletion. 26 * Each file to be deleted is registered with a handler object. 27 * When the handler object is garbage collected, the file is deleted. 28 * <p> 29 * In an environment with multiple class loaders (a servlet container, for 30 * example), you should consider stopping the background thread if it is no 31 * longer needed. This is done by invoking the method 32 * {@link #exitWhenFinished}, typically in 33 * {@link javax.servlet.ServletContextListener#contextDestroyed} or similar. 34 * 35 * @author Noel Bergman 36 * @author Martin Cooper 37 * @version $Id: FileCleaner.java 553012 2007-07-03 23:01:07Z ggregory $ 38 * @deprecated Use {@link FileCleaningTracker} 39 */ 40 @Deprecated 41 public class FileCleaner { 42 /** 43 * The instance to use for the deprecated, static methods. 44 */ 45 static final FileCleaningTracker theInstance = new FileCleaningTracker(); 46 47 //----------------------------------------------------------------------- 48 /** 49 * Track the specified file, using the provided marker, deleting the file 50 * when the marker instance is garbage collected. 51 * The {@link FileDeleteStrategy#NORMAL normal} deletion strategy will be used. 52 * 53 * @param file the file to be tracked, not null 54 * @param marker the marker object used to track the file, not null 55 * @throws NullPointerException if the file is null 56 * @deprecated Use {@link FileCleaningTracker#track(File, Object)}. 57 */ 58 @Deprecated 59 public static void track(File file, Object marker) { 60 theInstance.track(file, marker); 61 } 62 63 /** 64 * Track the specified file, using the provided marker, deleting the file 65 * when the marker instance is garbage collected. 66 * The speified deletion strategy is used. 67 * 68 * @param file the file to be tracked, not null 69 * @param marker the marker object used to track the file, not null 70 * @param deleteStrategy the strategy to delete the file, null means normal 71 * @throws NullPointerException if the file is null 72 * @deprecated Use {@link FileCleaningTracker#track(File, Object, FileDeleteStrategy)}. 73 */ 74 @Deprecated 75 public static void track(File file, Object marker, FileDeleteStrategy deleteStrategy) { 76 theInstance.track(file, marker, deleteStrategy); 77 } 78 79 /** 80 * Track the specified file, using the provided marker, deleting the file 81 * when the marker instance is garbage collected. 82 * The {@link FileDeleteStrategy#NORMAL normal} deletion strategy will be used. 83 * 84 * @param path the full path to the file to be tracked, not null 85 * @param marker the marker object used to track the file, not null 86 * @throws NullPointerException if the path is null 87 * @deprecated Use {@link FileCleaningTracker#track(String, Object)}. 88 */ 89 @Deprecated 90 public static void track(String path, Object marker) { 91 theInstance.track(path, marker); 92 } 93 94 /** 95 * Track the specified file, using the provided marker, deleting the file 96 * when the marker instance is garbage collected. 97 * The speified deletion strategy is used. 98 * 99 * @param path the full path to the file to be tracked, not null 100 * @param marker the marker object used to track the file, not null 101 * @param deleteStrategy the strategy to delete the file, null means normal 102 * @throws NullPointerException if the path is null 103 * @deprecated Use {@link FileCleaningTracker#track(String, Object, FileDeleteStrategy)}. 104 */ 105 @Deprecated 106 public static void track(String path, Object marker, FileDeleteStrategy deleteStrategy) { 107 theInstance.track(path, marker, deleteStrategy); 108 } 109 110 //----------------------------------------------------------------------- 111 /** 112 * Retrieve the number of files currently being tracked, and therefore 113 * awaiting deletion. 114 * 115 * @return the number of files being tracked 116 * @deprecated Use {@link FileCleaningTracker#getTrackCount()}. 117 */ 118 @Deprecated 119 public static int getTrackCount() { 120 return theInstance.getTrackCount(); 121 } 122 123 /** 124 * Call this method to cause the file cleaner thread to terminate when 125 * there are no more objects being tracked for deletion. 126 * <p> 127 * In a simple environment, you don't need this method as the file cleaner 128 * thread will simply exit when the JVM exits. In a more complex environment, 129 * with multiple class loaders (such as an application server), you should be 130 * aware that the file cleaner thread will continue running even if the class 131 * loader it was started from terminates. This can consitute a memory leak. 132 * <p> 133 * For example, suppose that you have developed a web application, which 134 * contains the commons-io jar file in your WEB-INF/lib directory. In other 135 * words, the FileCleaner class is loaded through the class loader of your 136 * web application. If the web application is terminated, but the servlet 137 * container is still running, then the file cleaner thread will still exist, 138 * posing a memory leak. 139 * <p> 140 * This method allows the thread to be terminated. Simply call this method 141 * in the resource cleanup code, such as {@link javax.servlet.ServletContextListener#contextDestroyed}. 142 * One called, no new objects can be tracked by the file cleaner. 143 * @deprecated Use {@link FileCleaningTracker#exitWhenFinished()}. 144 */ 145 @Deprecated 146 public static synchronized void exitWhenFinished() { 147 theInstance.exitWhenFinished(); 148 } 149 150 /** 151 * Returns the singleton instance, which is used by the deprecated, static methods. 152 * This is mainly useful for code, which wants to support the new 153 * {@link FileCleaningTracker} class while maintain compatibility with the 154 * deprecated {@link FileCleaner}. 155 * 156 * @return the singleton instance 157 */ 158 public static FileCleaningTracker getInstance() { 159 return theInstance; 160 } 161 } 162
