| /* |
| * 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 org.apache.commons.io; |
| |
| import java.io.File; |
| import java.io.IOException; |
| |
| /** |
| * Strategy for deleting files. |
| * <p> |
| * There is more than one way to delete a file. |
| * You may want to limit access to certain directories, to only delete |
| * directories if they are empty, or maybe to force deletion. |
| * <p> |
| * This class captures the strategy to use and is designed for user subclassing. |
| * |
| * @author Stephen Colebourne |
| * @version $Id: FileDeleteStrategy.java 453903 2006-10-07 13:47:06Z scolebourne $ |
| * @since Commons IO 1.3 |
| */ |
| public class FileDeleteStrategy { |
| |
| /** |
| * The singleton instance for normal file deletion, which does not permit |
| * the deletion of directories that are not empty. |
| */ |
| public static final FileDeleteStrategy NORMAL = new FileDeleteStrategy("Normal"); |
| /** |
| * The singleton instance for forced file deletion, which always deletes, |
| * even if the file represents a non-empty directory. |
| */ |
| public static final FileDeleteStrategy FORCE = new ForceFileDeleteStrategy(); |
| |
| /** The name of the strategy. */ |
| private final String name; |
| |
| //----------------------------------------------------------------------- |
| /** |
| * Restricted constructor. |
| * |
| * @param name the name by which the strategy is known |
| */ |
| protected FileDeleteStrategy(String name) { |
| this.name = name; |
| } |
| |
| //----------------------------------------------------------------------- |
| /** |
| * Deletes the file object, which may be a file or a directory. |
| * All <code>IOException</code>s are caught and false returned instead. |
| * If the file does not exist or is null, true is returned. |
| * <p> |
| * Subclass writers should override {@link #doDelete(File)}, not this method. |
| * |
| * @param fileToDelete the file to delete, null returns true |
| * @return true if the file was deleted, or there was no such file |
| */ |
| public boolean deleteQuietly(File fileToDelete) { |
| if (fileToDelete == null || fileToDelete.exists() == false) { |
| return true; |
| } |
| try { |
| return doDelete(fileToDelete); |
| } catch (IOException ex) { |
| return false; |
| } |
| } |
| |
| /** |
| * Deletes the file object, which may be a file or a directory. |
| * If the file does not exist, the method just returns. |
| * <p> |
| * Subclass writers should override {@link #doDelete(File)}, not this method. |
| * |
| * @param fileToDelete the file to delete, not null |
| * @throws NullPointerException if the file is null |
| * @throws IOException if an error occurs during file deletion |
| */ |
| public void delete(File fileToDelete) throws IOException { |
| if (fileToDelete.exists() && doDelete(fileToDelete) == false) { |
| throw new IOException("Deletion failed: " + fileToDelete); |
| } |
| } |
| |
| /** |
| * Actually deletes the file object, which may be a file or a directory. |
| * <p> |
| * This method is designed for subclasses to override. |
| * The implementation may return either false or an <code>IOException</code> |
| * when deletion fails. The {@link #delete(File)} and {@link #deleteQuietly(File)} |
| * methods will handle either response appropriately. |
| * A check has been made to ensure that the file will exist. |
| * <p> |
| * This implementation uses {@link File#delete()}. |
| * |
| * @param fileToDelete the file to delete, exists, not null |
| * @return true if the file was deleteds |
| * @throws NullPointerException if the file is null |
| * @throws IOException if an error occurs during file deletion |
| */ |
| protected boolean doDelete(File fileToDelete) throws IOException { |
| return fileToDelete.delete(); |
| } |
| |
| //----------------------------------------------------------------------- |
| /** |
| * Gets a string describing the delete strategy. |
| * |
| * @return a string describing the delete strategy |
| */ |
| public String toString() { |
| return "FileDeleteStrategy[" + name + "]"; |
| } |
| |
| //----------------------------------------------------------------------- |
| /** |
| * Force file deletion strategy. |
| */ |
| static class ForceFileDeleteStrategy extends FileDeleteStrategy { |
| /** Default Constructor */ |
| ForceFileDeleteStrategy() { |
| super("Force"); |
| } |
| |
| /** |
| * Deletes the file object. |
| * <p> |
| * This implementation uses <code>FileUtils.forceDelete() <code> |
| * if the file exists. |
| * |
| * @param fileToDelete the file to delete, not null |
| * @return Always returns <code>true</code> |
| * @throws NullPointerException if the file is null |
| * @throws IOException if an error occurs during file deletion |
| */ |
| protected boolean doDelete(File fileToDelete) throws IOException { |
| FileUtils.forceDelete(fileToDelete); |
| return true; |
| } |
| } |
| |
| } |