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.filefilter;
18
19import java.io.File;
20import java.io.FileFilter;
21import java.io.FilenameFilter;
22import java.io.Serializable;
23
24/**
25 * This class turns a Java FileFilter or FilenameFilter into an IO FileFilter.
26 *
27 * @since Commons IO 1.0
28 * @version $Revision: 591058 $ $Date: 2007-11-01 15:47:05 +0000 (Thu, 01 Nov 2007) $
29 *
30 * @author Stephen Colebourne
31 */
32public class DelegateFileFilter extends AbstractFileFilter implements Serializable {
33
34    /** The Filename filter */
35    private final FilenameFilter filenameFilter;
36    /** The File filter */
37    private final FileFilter fileFilter;
38
39    /**
40     * Constructs a delegate file filter around an existing FilenameFilter.
41     *
42     * @param filter  the filter to decorate
43     */
44    public DelegateFileFilter(FilenameFilter filter) {
45        if (filter == null) {
46            throw new IllegalArgumentException("The FilenameFilter must not be null");
47        }
48        this.filenameFilter = filter;
49        this.fileFilter = null;
50    }
51
52    /**
53     * Constructs a delegate file filter around an existing FileFilter.
54     *
55     * @param filter  the filter to decorate
56     */
57    public DelegateFileFilter(FileFilter filter) {
58        if (filter == null) {
59            throw new IllegalArgumentException("The FileFilter must not be null");
60        }
61        this.fileFilter = filter;
62        this.filenameFilter = null;
63    }
64
65    /**
66     * Checks the filter.
67     *
68     * @param file  the file to check
69     * @return true if the filter matches
70     */
71    public boolean accept(File file) {
72        if (fileFilter != null) {
73            return fileFilter.accept(file);
74        } else {
75            return super.accept(file);
76        }
77    }
78
79    /**
80     * Checks the filter.
81     *
82     * @param dir  the directory
83     * @param name  the filename in the directory
84     * @return true if the filter matches
85     */
86    public boolean accept(File dir, String name) {
87        if (filenameFilter != null) {
88            return filenameFilter.accept(dir, name);
89        } else {
90            return super.accept(dir, name);
91        }
92    }
93
94    /**
95     * Provide a String representaion of this file filter.
96     *
97     * @return a String representaion
98     */
99    public String toString() {
100        String delegate = (fileFilter != null ? fileFilter.toString() : filenameFilter.toString());
101        return super.toString() + "(" + delegate + ")";
102    }
103
104}
105