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.io.filefilter;
18
19 import java.io.File;
20 import java.io.Serializable;
21 import java.nio.file.FileVisitResult;
22 import java.nio.file.Files;
23 import java.nio.file.Path;
24 import java.nio.file.attribute.BasicFileAttributes;
25
26 /**
27 * This filter accepts {@link File}s that are files (not directories).
28 * <p>
29 * For example, here is how to print out a list of the real files
30 * within the current directory:
31 * </p>
32 * <h2>Using Classic IO</h2>
33 * <pre>
34 * File dir = FileUtils.current();
35 * String[] files = dir.list(FileFileFilter.INSTANCE);
36 * for (String file : files) {
37 * System.out.println(file);
38 * }
39 * </pre>
40 *
41 * <h2>Using NIO</h2>
42 * <pre>
43 * final Path dir = PathUtils.current();
44 * final AccumulatorPathVisitor visitor = AccumulatorPathVisitor.withLongCounters(FileFileFilter.INSTANCE);
45 * //
46 * // Walk one dir
47 * Files.<b>walkFileTree</b>(dir, Collections.emptySet(), 1, visitor);
48 * System.out.println(visitor.getPathCounters());
49 * System.out.println(visitor.getFileList());
50 * //
51 * visitor.getPathCounters().reset();
52 * //
53 * // Walk dir tree
54 * Files.<b>walkFileTree</b>(dir, visitor);
55 * System.out.println(visitor.getPathCounters());
56 * System.out.println(visitor.getDirList());
57 * System.out.println(visitor.getFileList());
58 * </pre>
59 * <h2>Deprecating Serialization</h2>
60 * <p>
61 * <em>Serialization is deprecated and will be removed in 3.0.</em>
62 * </p>
63 *
64 * @since 1.3
65 * @see FileFilterUtils#fileFileFilter()
66 */
67 public class FileFileFilter extends AbstractFileFilter implements Serializable {
68
69 /**
70 * Singleton instance of file filter.
71 *
72 * @since 2.9.0
73 */
74 public static final IOFileFilter INSTANCE = new FileFileFilter();
75
76 /**
77 * Singleton instance of file filter.
78 *
79 * @deprecated Use {@link #INSTANCE}.
80 */
81 @Deprecated
82 public static final IOFileFilter FILE = INSTANCE;
83
84 private static final long serialVersionUID = 5345244090827540862L;
85
86 /**
87 * Restrictive constructor.
88 */
89 protected FileFileFilter() {
90 }
91
92 /**
93 * Checks to see if the file is a file.
94 *
95 * @param file the File to check
96 * @return true if the file is a file
97 */
98 @Override
99 public boolean accept(final File file) {
100 return file != null && file.isFile();
101 }
102
103 /**
104 * Checks to see if the file is a file.
105 * @param file the File to check
106 *
107 * @return true if the file is a file
108 * @since 2.9.0
109 */
110 @Override
111 public FileVisitResult accept(final Path file, final BasicFileAttributes attributes) {
112 return toFileVisitResult(file != null && Files.isRegularFile(file));
113 }
114
115 }