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.FileContent; 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.FileSystemException; 26 27 /** 28 * Filters files based on size, can filter either smaller files or files equal 29 * to or larger than a given threshold. 30 * <p> 31 * For example, to print all files and directories in the current directory 32 * whose size is greater than 1 MB: 33 * </p> 34 * 35 * <pre> 36 * FileSystemManager fsManager = VFS.getManager(); 37 * FileObject dir = fsManager.toFileObject(new File(".")); 38 * SizeFileFilter filter = new SizeFileFilter(1024 * 1024); 39 * FileObject[] files = dir.findFiles(new FileFilterSelector(filter)); 40 * for (int i = 0; i < files.length; i++) { 41 * System.out.println(files[i]); 42 * } 43 * </pre> 44 * 45 * @author This code was originally ported from Apache Commons IO File Filter 46 * @see "http://commons.apache.org/proper/commons-io/" 47 * @since 2.4 48 */ 49 public class SizeFileFilter implements FileFilter, Serializable { 50 51 private static final long serialVersionUID = 1L; 52 53 /** Whether the files accepted will be larger or smaller. */ 54 private final boolean acceptLarger; 55 56 /** The size threshold. */ 57 private final long size; 58 59 /** 60 * Constructs a new size file filter for files equal to or larger than a certain 61 * size. 62 * 63 * @param size the threshold size of the files - Must be non-negative. 64 */ 65 public SizeFileFilter(final long size) { 66 this(size, true); 67 } 68 69 /** 70 * Constructs a new size file filter for files based on a certain size 71 * threshold. 72 * 73 * @param size the threshold size of the files - Must be non-negative. 74 * @param acceptLarger if true, files equal to or larger are accepted, otherwise 75 * smaller ones (but not equal to) 76 */ 77 public SizeFileFilter(final long size, final boolean acceptLarger) { 78 if (size < 0) { 79 throw new IllegalArgumentException("The size must be non-negative"); 80 } 81 this.size = size; 82 this.acceptLarger = acceptLarger; 83 } 84 85 /** 86 * Checks to see if the size of the file is favorable. 87 * <p> 88 * If size equals threshold and smaller files are required, file <b>IS NOT</b> 89 * selected. If size equals threshold and larger files are required, file 90 * <b>IS</b> selected. 91 * </p> 92 * <p> 93 * Non-existing files return always false (will never be accepted). 94 * </p> 95 * 96 * @param fileSelectInfo the File to check 97 * 98 * @return true if the file name matches 99 * @throws FileSystemException Thrown for file system errors. 100 */ 101 @Override 102 public boolean accept(final FileSelectInfo fileSelectInfo) throws FileSystemException { 103 try (final FileObject file = fileSelectInfo.getFile()) { 104 if (!file.exists()) { 105 return false; 106 } 107 try (final FileContent content = file.getContent()) { 108 final long length = content.getSize(); 109 final boolean smaller = length < size; 110 return acceptLarger != smaller; 111 } 112 } 113 } 114 115 /** 116 * Provide a String representation of this file filter. 117 * 118 * @return a String representation 119 */ 120 @Override 121 public String toString() { 122 final String condition = acceptLarger ? ">=" : "<"; 123 return super.toString() + "(" + condition + size + ")"; 124 } 125 126 }