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.FileFilter;
22 import org.apache.commons.vfs2.FileSelectInfo;
23 import org.apache.commons.vfs2.FileSystemException;
24
25 /**
26 * This filter produces a logical NOT of the filters specified.
27 *
28 * @author This code was originally ported from Apache Commons IO File Filter
29 * @see "http://commons.apache.org/proper/commons-io/"
30 * @since 2.4
31 */
32 public class NotFileFilter implements FileFilter, Serializable {
33
34 private static final long serialVersionUID = 1L;
35
36 /** The filter. */
37 private final FileFilter filter;
38
39 /**
40 * Constructs a new file filter that NOTs the result of another filter.
41 *
42 * @param filter the filter, must not be null
43 */
44 public NotFileFilter(final FileFilter filter) {
45 if (filter == null) {
46 throw new IllegalArgumentException("The filter must not be null");
47 }
48 this.filter = filter;
49 }
50
51 /**
52 * Returns the logical NOT of the underlying filter's return value for the same
53 * File.
54 *
55 * @param fileSelectInfo the File to check
56 *
57 * @return {@code true} if the filter returns {@code false}
58 * @throws FileSystemException Thrown for file system errors.
59 */
60 @Override
61 public boolean accept(final FileSelectInfo fileSelectInfo) throws FileSystemException {
62 return !filter.accept(fileSelectInfo);
63 }
64
65 /**
66 * Provide a String representation of this file filter.
67 *
68 * @return a String representation
69 */
70 @Override
71 public String toString() {
72 return super.toString() + "(" + filter.toString() + ")";
73 }
74
75 }