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 */
17package org.apache.commons.io.comparator;
18
19import java.io.File;
20import java.io.Serializable;
21import java.util.Comparator;
22
23/**
24 * Compare two files using the <b>default</b> {@link File#compareTo(File)} method.
25 * <p>
26 * This comparator can be used to sort lists or arrays of files
27 * by using the default file comparison.
28 * <p>
29 * Example of sorting a list of files using the
30 * {@link #DEFAULT_COMPARATOR} singleton instance:
31 * <pre>
32 *       List&lt;File&gt; list = ...
33 *       Collections.sort(list, DefaultFileComparator.DEFAULT_COMPARATOR);
34 * </pre>
35 * <p>
36 * Example of doing a <i>reverse</i> sort of an array of files using the
37 * {@link #DEFAULT_REVERSE} singleton instance:
38 * <pre>
39 *       File[] array = ...
40 *       Arrays.sort(array, DefaultFileComparator.DEFAULT_REVERSE);
41 * </pre>
42 * <p>
43 *
44 * @version $Revision: 609243 $ $Date: 2008-01-06 00:30:42 +0000 (Sun, 06 Jan 2008) $
45 * @since Commons IO 1.4
46 */
47public class DefaultFileComparator implements Comparator<File>, Serializable {
48
49    /** Singleton default comparator instance */
50    public static final Comparator<File> DEFAULT_COMPARATOR = new DefaultFileComparator();
51
52    /** Singleton reverse default comparator instance */
53    public static final Comparator<File> DEFAULT_REVERSE = new ReverseComparator<File>(DEFAULT_COMPARATOR);
54
55    /**
56     * Compare the two files using the {@link File#compareTo(File)} method.
57     *
58     * @param obj1 The first file to compare
59     * @param obj2 The second file to compare
60     * @return the result of calling file1's
61     * {@link File#compareTo(File)} with file2 as the parameter.
62     */
63    public int compare(File file1, File file2) {
64        return file1.compareTo(file2);
65    }
66}
67