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.FileFilter; 022import org.apache.commons.vfs2.FileSelectInfo; 023import org.apache.commons.vfs2.FileSystemException; 024 025/** 026 * This filter accepts {@code File}s that are hidden. 027 * <p> 028 * Example, showing how to print out a list of the current directory's 029 * <em>hidden</em> files: 030 * </p> 031 * 032 * <pre> 033 * FileSystemManager fsManager = VFS.getManager(); 034 * FileObject dir = fsManager.toFileObject(new File(".")); 035 * FileObject[] files = dir.findFiles(new FileFilterSelector(HiddenFileFilter.HIDDEN)); 036 * for (int i = 0; i < files.length; i++) { 037 * System.out.println(files[i]); 038 * } 039 * </pre> 040 * 041 * <p> 042 * Example, showing how to print out a list of the current directory's 043 * <em>visible</em> (i.e. not hidden) files: 044 * </p> 045 * 046 * <pre> 047 * FileSystemManager fsManager = VFS.getManager(); 048 * FileObject dir = fsManager.toFileObject(new File(".")); 049 * FileObject[] files = dir.findFiles(new FileFilterSelector(HiddenFileFilter.VISIBLE)); 050 * for (int i = 0; i < files.length; i++) { 051 * System.out.println(files[i]); 052 * } 053 * </pre> 054 * 055 * @author This code was originally ported from Apache Commons IO File Filter 056 * @see "https://commons.apache.org/proper/commons-io/" 057 * @since 2.4 058 */ 059public class HiddenFileFilter implements FileFilter, Serializable { 060 061 /** Singleton instance of <em>hidden</em> filter. */ 062 public static final FileFilter HIDDEN = new HiddenFileFilter(); 063 064 /** Singleton instance of <em>visible</em> filter. */ 065 public static final FileFilter VISIBLE = new NotFileFilter(HIDDEN); 066 067 private static final long serialVersionUID = 1L; 068 069 /** 070 * Restrictive constructor. 071 */ 072 protected HiddenFileFilter() { 073 } 074 075 /** 076 * Checks to see if the file is hidden. Non-existing files won't be accepted. 077 * 078 * @param fileSelectInfo the File to check 079 * @return {@code true} if the file is <em>hidden</em>, otherwise {@code false}. 080 * @throws FileSystemException Thrown for file system errors. 081 */ 082 @Override 083 public boolean accept(final FileSelectInfo fileSelectInfo) throws FileSystemException { 084 if (!fileSelectInfo.getFile().exists()) { 085 return false; 086 } 087 return fileSelectInfo.getFile().isHidden(); 088 } 089 090}