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.io.filefilter; 018 019import java.io.File; 020import java.io.Serializable; 021import java.nio.file.FileVisitResult; 022import java.nio.file.Path; 023import java.nio.file.attribute.BasicFileAttributes; 024 025/** 026 * A file filter that always returns true. 027 * 028 * @since 1.0 029 * @see FileFilterUtils#trueFileFilter() 030 */ 031public class TrueFileFilter implements IOFileFilter, Serializable { 032 033 private static final String TO_STRING = Boolean.TRUE.toString(); 034 035 private static final long serialVersionUID = 8782512160909720199L; 036 037 /** 038 * Singleton instance of true filter. 039 * 040 * @since 1.3 041 */ 042 public static final IOFileFilter TRUE = new TrueFileFilter(); 043 044 /** 045 * Singleton instance of true filter. Please use the identical TrueFileFilter.TRUE constant. The new name is more 046 * JDK 1.5 friendly as it doesn't clash with other values when using static imports. 047 */ 048 public static final IOFileFilter INSTANCE = TRUE; 049 050 /** 051 * Restrictive constructor. 052 */ 053 protected TrueFileFilter() { 054 } 055 056 /** 057 * Returns true. 058 * 059 * @param file the file to check (ignored) 060 * @return true 061 */ 062 @Override 063 public boolean accept(final File file) { 064 return true; 065 } 066 067 /** 068 * Returns true. 069 * 070 * @param dir the directory to check (ignored) 071 * @param name the file name (ignored) 072 * @return true 073 */ 074 @Override 075 public boolean accept(final File dir, final String name) { 076 return true; 077 } 078 079 /** 080 * Returns true. 081 * @param file the file to check (ignored) 082 * 083 * @return true 084 * @since 2.9.0 085 */ 086 @Override 087 public FileVisitResult accept(final Path file, final BasicFileAttributes attributes) { 088 return FileVisitResult.CONTINUE; 089 } 090 091 @Override 092 public IOFileFilter negate() { 093 return FalseFileFilter.INSTANCE; 094 } 095 096 @Override 097 public IOFileFilter or(final IOFileFilter fileFilter) { 098 // TRUE OR expression <=> true 099 return INSTANCE; 100 } 101 102 @Override 103 public IOFileFilter and(final IOFileFilter fileFilter) { 104 // TRUE AND expression <=> expression 105 return fileFilter; 106 } 107 108 @Override 109 public String toString() { 110 return TO_STRING; 111 } 112}