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.vfs2.filter; 018 019import java.io.Serializable; 020 021import org.apache.commons.vfs2.Capability; 022import org.apache.commons.vfs2.FileFilter; 023import org.apache.commons.vfs2.FileObject; 024import org.apache.commons.vfs2.FileSelectInfo; 025import org.apache.commons.vfs2.FileSystem; 026import org.apache.commons.vfs2.FileSystemException; 027 028/** 029 * This filter accepts {@code File}s that can be written to. 030 * <p> 031 * Example, showing how to print out a list of the current directory's 032 * <em>writable</em> files: 033 * </p> 034 * 035 * <pre> 036 * FileSystemManager fsManager = VFS.getManager(); 037 * FileObject dir = fsManager.toFileObject(new File(".")); 038 * FileObject[] files = dir.findFiles(new FileFilterSelector(CanWriteFileFilter.CAN_WRITE)); 039 * for (int i = 0; i < files.length; i++) { 040 * System.out.println(files[i]); 041 * } 042 * </pre> 043 * 044 * <p> 045 * Example, showing how to print out a list of the current directory's 046 * <em>un-writable</em> files: 047 * </p> 048 * 049 * <pre> 050 * FileSystemManager fsManager = VFS.getManager(); 051 * FileObject dir = fsManager.toFileObject(new File(".")); 052 * FileObject[] files = dir.findFiles(new FileFilterSelector(CanWriteFileFilter.CANNOT_WRITE)); 053 * for (int i = 0; i < files.length; i++) { 054 * System.out.println(files[i]); 055 * } 056 * </pre> 057 * 058 * <p> 059 * <strong>N.B.</strong> For read-only files, use 060 * {@code CanReadFileFilter.READ_ONLY}. 061 * </p> 062 * 063 * @author This code was originally ported from Apache Commons IO File Filter 064 * @see "https://commons.apache.org/proper/commons-io/" 065 * @since 2.4 066 */ 067public class CanWriteFileFilter implements FileFilter, Serializable { 068 069 /** Singleton instance of <em>writable</em> filter. */ 070 public static final FileFilter CAN_WRITE = new CanWriteFileFilter(); 071 072 /** Singleton instance of not <em>writable</em> filter. */ 073 public static final FileFilter CANNOT_WRITE = new NotFileFilter(CAN_WRITE); 074 075 private static final long serialVersionUID = 1L; 076 077 /** 078 * Restrictive constructor. 079 */ 080 protected CanWriteFileFilter() { 081 } 082 083 /** 084 * Checks to see if the file can be written to. 085 * 086 * @param fileSelectInfo the File to check 087 * @return {@code true} if the file can be written to, otherwise {@code false}. 088 * @throws FileSystemException Thrown for file system errors. 089 */ 090 @Override 091 public boolean accept(final FileSelectInfo fileSelectInfo) throws FileSystemException { 092 try (FileObject file = fileSelectInfo.getFile()) { 093 final FileSystem fileSystem = file.getFileSystem(); 094 if (file.exists()) { 095 if (!fileSystem.hasCapability(Capability.WRITE_CONTENT)) { 096 return false; 097 } 098 return file.isWriteable(); 099 } 100 if (!fileSystem.hasCapability(Capability.CREATE)) { 101 return false; 102 } 103 return file.getParent().isWriteable(); 104 } 105 } 106 107}