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.vfs2.filter; 18 19 import java.io.Serializable; 20 21 import org.apache.commons.vfs2.Capability; 22 import org.apache.commons.vfs2.FileFilter; 23 import org.apache.commons.vfs2.FileObject; 24 import org.apache.commons.vfs2.FileSelectInfo; 25 import org.apache.commons.vfs2.FileSystem; 26 import org.apache.commons.vfs2.FileSystemException; 27 28 /** 29 * This filter accepts {@code File}s that can be written to. 30 * <p> 31 * Example, showing how to print out a list of the current directory's 32 * <em>writable</em> files: 33 * </p> 34 * 35 * <pre> 36 * FileSystemManager fsManager = VFS.getManager(); 37 * FileObject dir = fsManager.toFileObject(new File(".")); 38 * FileObject[] files = dir.findFiles(new FileFilterSelector(CanWriteFileFilter.CAN_WRITE)); 39 * for (int i = 0; i < files.length; i++) { 40 * System.out.println(files[i]); 41 * } 42 * </pre> 43 * 44 * <p> 45 * Example, showing how to print out a list of the current directory's 46 * <em>un-writable</em> files: 47 * </p> 48 * 49 * <pre> 50 * FileSystemManager fsManager = VFS.getManager(); 51 * FileObject dir = fsManager.toFileObject(new File(".")); 52 * FileObject[] files = dir.findFiles(new FileFilterSelector(CanWriteFileFilter.CANNOT_WRITE)); 53 * for (int i = 0; i < files.length; i++) { 54 * System.out.println(files[i]); 55 * } 56 * </pre> 57 * 58 * <p> 59 * <strong>N.B.</strong> For read-only files, use 60 * {@code CanReadFileFilter.READ_ONLY}. 61 * </p> 62 * 63 * @author This code was originally ported from Apache Commons IO File Filter 64 * @see "https://commons.apache.org/proper/commons-io/" 65 * @since 2.4 66 */ 67 public class CanWriteFileFilter implements FileFilter, Serializable { 68 69 /** Singleton instance of <em>writable</em> filter. */ 70 public static final FileFilter CAN_WRITE = new CanWriteFileFilter(); 71 72 /** Singleton instance of not <em>writable</em> filter. */ 73 public static final FileFilter CANNOT_WRITE = new NotFileFilter(CAN_WRITE); 74 75 private static final long serialVersionUID = 1L; 76 77 /** 78 * Restrictive constructor. 79 */ 80 protected CanWriteFileFilter() { 81 } 82 83 /** 84 * Checks to see if the file can be written to. 85 * 86 * @param fileSelectInfo the File to check 87 * @return {@code true} if the file can be written to, otherwise {@code false}. 88 * @throws FileSystemException Thrown for file system errors. 89 */ 90 @Override 91 public boolean accept(final FileSelectInfo fileSelectInfo) throws FileSystemException { 92 try (FileObject file = fileSelectInfo.getFile()) { 93 final FileSystem fileSystem = file.getFileSystem(); 94 if (file.exists()) { 95 if (!fileSystem.hasCapability(Capability.WRITE_CONTENT)) { 96 return false; 97 } 98 return file.isWriteable(); 99 } 100 if (!fileSystem.hasCapability(Capability.CREATE)) { 101 return false; 102 } 103 return file.getParent().isWriteable(); 104 } 105 } 106 107 }