001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.commons.io.filefilter;
018
019import java.io.File;
020import java.io.FileFilter;
021import java.io.FilenameFilter;
022import java.io.Serializable;
023
024/**
025 * This class turns a Java FileFilter or FilenameFilter into an IO FileFilter.
026 *
027 * @since 1.0
028 * @version $Id: DelegateFileFilter.java 1642757 2014-12-01 21:09:30Z sebb $
029 *
030 * @see FileFilterUtils#asFileFilter(FileFilter)
031 * @see FileFilterUtils#asFileFilter(FilenameFilter)
032 */
033public class DelegateFileFilter extends AbstractFileFilter implements Serializable {
034
035    private static final long serialVersionUID = -8723373124984771318L;
036    /** The Filename filter */
037    private final FilenameFilter filenameFilter;
038    /** The File filter */
039    private final FileFilter fileFilter;
040
041    /**
042     * Constructs a delegate file filter around an existing FilenameFilter.
043     *
044     * @param filter  the filter to decorate
045     */
046    public DelegateFileFilter(final FilenameFilter filter) {
047        if (filter == null) {
048            throw new IllegalArgumentException("The FilenameFilter must not be null");
049        }
050        this.filenameFilter = filter;
051        this.fileFilter = null;
052    }
053
054    /**
055     * Constructs a delegate file filter around an existing FileFilter.
056     *
057     * @param filter  the filter to decorate
058     */
059    public DelegateFileFilter(final FileFilter filter) {
060        if (filter == null) {
061            throw new IllegalArgumentException("The FileFilter must not be null");
062        }
063        this.fileFilter = filter;
064        this.filenameFilter = null;
065    }
066
067    /**
068     * Checks the filter.
069     *
070     * @param file  the file to check
071     * @return true if the filter matches
072     */
073    @Override
074    public boolean accept(final File file) {
075        if (fileFilter != null) {
076            return fileFilter.accept(file);
077        } else {
078            return super.accept(file);
079        }
080    }
081
082    /**
083     * Checks the filter.
084     *
085     * @param dir  the directory
086     * @param name  the filename in the directory
087     * @return true if the filter matches
088     */
089    @Override
090    public boolean accept(final File dir, final String name) {
091        if (filenameFilter != null) {
092            return filenameFilter.accept(dir, name);
093        } else {
094            return super.accept(dir, name);
095        }
096    }
097
098    /**
099     * Provide a String representaion of this file filter.
100     *
101     * @return a String representaion
102     */
103    @Override
104    public String toString() {
105        final String delegate = fileFilter != null ? fileFilter.toString() : filenameFilter.toString();
106        return super.toString() + "(" + delegate + ")";
107    }
108
109}