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; 020import java.util.regex.Pattern; 021 022import org.apache.commons.vfs2.FileFilter; 023import org.apache.commons.vfs2.FileSelectInfo; 024 025/** 026 * Filters files using supplied regular expression(s). 027 * <p> 028 * See java.util.regex.Pattern for regex matching rules. 029 * </p> 030 * 031 * <p> 032 * For example, to retrieve and print all Java files where the name matched the 033 * regular expression in the current directory: 034 * </p> 035 * 036 * <pre> 037 * FileSystemManager fsManager = VFS.getManager(); 038 * FileObject dir = fsManager.toFileObject(new File(".")); 039 * FileObject[] files = dir.findFiles(new FileFilterSelector(new RegexFileFilter("ˆ.*[tT]est(-\\d+)?\\.java$"))); 040 * for (int i = 0; i < files.length; i++) { 041 * System.out.println(files[i]); 042 * } 043 * </pre> 044 * 045 * @author This code was originally ported from Apache Commons IO File Filter 046 * @see "https://commons.apache.org/proper/commons-io/" 047 * @since 2.4 048 */ 049public class RegexFileFilter implements FileFilter, Serializable { 050 051 /** Exception message when no pattern is given in the constructor. */ 052 public static final String PATTERN_IS_MISSING = "Pattern is missing"; 053 054 private static final long serialVersionUID = 1L; 055 056 /** The regular expression pattern that will be used to match file names. */ 057 private final Pattern pattern; 058 059 /** 060 * Constructs a new regular expression filter for a compiled regular expression. 061 * 062 * @param pattern regular expression to match - Cannot be null 063 */ 064 public RegexFileFilter(final Pattern pattern) { 065 if (pattern == null) { 066 throw new IllegalArgumentException(PATTERN_IS_MISSING); 067 } 068 069 this.pattern = pattern; 070 } 071 072 /** 073 * Constructs a new regular expression filter. 074 * 075 * @param pattern regular string expression to match - Cannot be null 076 */ 077 public RegexFileFilter(final String pattern) { 078 if (pattern == null) { 079 throw new IllegalArgumentException(PATTERN_IS_MISSING); 080 } 081 082 this.pattern = Pattern.compile(pattern); 083 } 084 085 /** 086 * Constructs a new regular expression filter with the specified flags. 087 * 088 * @param pattern regular string expression to match 089 * @param flags pattern flags - e.g. {@link Pattern#CASE_INSENSITIVE} 090 */ 091 public RegexFileFilter(final String pattern, final int flags) { 092 if (pattern == null) { 093 throw new IllegalArgumentException(PATTERN_IS_MISSING); 094 } 095 this.pattern = Pattern.compile(pattern, flags); 096 } 097 098 /** 099 * Constructs a new regular expression filter with the specified flags case 100 * sensitivity. 101 * 102 * @param pattern regular string expression to match - Cannot be null 103 * @param caseSensitivity how to handle case sensitivity, null means 104 * case-sensitive 105 */ 106 public RegexFileFilter(final String pattern, final IOCase caseSensitivity) { 107 if (pattern == null) { 108 throw new IllegalArgumentException(PATTERN_IS_MISSING); 109 } 110 int flags = 0; 111 if (caseSensitivity != null && !caseSensitivity.isCaseSensitive()) { 112 flags = Pattern.CASE_INSENSITIVE; 113 } 114 this.pattern = Pattern.compile(pattern, flags); 115 } 116 117 /** 118 * Checks to see if the file name matches one of the regular expressions. 119 * 120 * @param fileSelectInfo the File to check 121 * @return true if the file matches one of the regular expressions 122 */ 123 @Override 124 public boolean accept(final FileSelectInfo fileSelectInfo) { 125 final String name = fileSelectInfo.getFile().getName().getBaseName(); 126 return pattern.matcher(name).matches(); 127 } 128 129}