| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package libcore.io; |
| |
| |
| import java.io.File; |
| import java.util.ArrayList; |
| import java.util.Collections; |
| |
| /** |
| * Implements the actual DeleteOnExit mechanism. Is registered as a shutdown |
| * hook in the Runtime, once it is actually being used. |
| */ |
| public class DeleteOnExit extends Thread { |
| |
| /** |
| * Our singleton instance. |
| */ |
| private static DeleteOnExit instance; |
| |
| /** |
| * Returns our singleton instance, creating it if necessary. |
| */ |
| public static synchronized DeleteOnExit getInstance() { |
| if (instance == null) { |
| instance = new DeleteOnExit(); |
| Runtime.getRuntime().addShutdownHook(instance); |
| } |
| |
| return instance; |
| } |
| |
| /** |
| * Our list of files scheduled for deletion. |
| */ |
| private final ArrayList<String> files = new ArrayList<String>(); |
| |
| |
| private DeleteOnExit() { |
| } |
| |
| /** |
| * Schedules a file for deletion. |
| * |
| * @param filename The file to delete. |
| */ |
| public void addFile(String filename) { |
| synchronized (files) { |
| if (!files.contains(filename)) { |
| files.add(filename); |
| } |
| } |
| } |
| |
| /** |
| * Does the actual work. Note we (a) first sort the files lexicographically |
| * and then (b) delete them in reverse order. This is to make sure files |
| * get deleted before their parent directories. |
| */ |
| @Override |
| public void run() { |
| Collections.sort(files); |
| for (int i = files.size() - 1; i >= 0; i--) { |
| new File(files.get(i)).delete(); |
| } |
| } |
| } |