14fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy/* 24fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * Licensed to the Apache Software Foundation (ASF) under one or more 34fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * contributor license agreements. See the NOTICE file distributed with 44fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * this work for additional information regarding copyright ownership. 54fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * The ASF licenses this file to You under the Apache License, Version 2.0 64fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * (the "License"); you may not use this file except in compliance with 74fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * the License. You may obtain a copy of the License at 84fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * 94fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * http://www.apache.org/licenses/LICENSE-2.0 104fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * 114fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * Unless required by applicable law or agreed to in writing, software 124fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * distributed under the License is distributed on an "AS IS" BASIS, 134fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 144fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * See the License for the specific language governing permissions and 154fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * limitations under the License. 164fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy */ 174fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedypackage org.apache.commons.io.comparator; 184fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy 194fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedyimport java.io.File; 204fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedyimport java.io.Serializable; 214fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedyimport java.util.Comparator; 224fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy 234fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy/** 244fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * Compare the <b>last modified date/time</b> of two files for order 254fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * (see {@link File#lastModified()}). 264fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * <p> 274fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * This comparator can be used to sort lists or arrays of files 284fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * by their last modified date/time. 294fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * <p> 304fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * Example of sorting a list of files using the 314fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * {@link #LASTMODIFIED_COMPARATOR} singleton instance: 324fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * <pre> 334fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * List<File> list = ... 344fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * Collections.sort(list, LastModifiedFileComparator.LASTMODIFIED_COMPARATOR); 354fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * </pre> 364fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * <p> 374fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * Example of doing a <i>reverse</i> sort of an array of files using the 384fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * {@link #LASTMODIFIED_REVERSE} singleton instance: 394fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * <pre> 404fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * File[] array = ... 414fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * Arrays.sort(array, LastModifiedFileComparator.LASTMODIFIED_REVERSE); 424fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * </pre> 434fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * <p> 444fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * 454fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * @version $Revision: 609243 $ $Date: 2008-01-06 00:30:42 +0000 (Sun, 06 Jan 2008) $ 464fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * @since Commons IO 1.4 474fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy */ 484fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedypublic class LastModifiedFileComparator implements Comparator<File>, Serializable { 494fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy 504fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy /** Last modified comparator instance */ 514fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy public static final Comparator<File> LASTMODIFIED_COMPARATOR = new LastModifiedFileComparator(); 524fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy 534fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy /** Reverse last modified comparator instance */ 544fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy public static final Comparator<File> LASTMODIFIED_REVERSE = new ReverseComparator<File>(LASTMODIFIED_COMPARATOR); 554fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy 564fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy /** 574fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * Compare the last the last modified date/time of two files. 584fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * 594fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * @param obj1 The first file to compare 604fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * @param obj2 The second file to compare 614fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * @return a negative value if the first file's lastmodified date/time 624fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * is less than the second, zero if the lastmodified date/time are the 634fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * same and a positive value if the first files lastmodified date/time 644fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * is greater than the second file. 654fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy * 664fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy */ 674fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy public int compare(File file1, File file2) { 684fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy long result = file1.lastModified() - file2.lastModified(); 694fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy if (result < 0) { 704fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy return -1; 714fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy } else if (result > 0) { 724fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy return 1; 734fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy } else { 744fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy return 0; 754fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy } 764fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy } 774fa0a3295bcacbdcd6a9e7709cf17aa5adb90356Scott Kennedy} 78