001/*
002 * Copyright (c) 2005 Einar Pehrson <einar@pehrson.nu>.
003 *
004 * This file is part of
005 * CleanSheets - a spreadsheet application for the Java platform.
006 *
007 * CleanSheets is free software; you can redistribute it and/or modify
008 * it under the terms of the GNU General Public License as published by
009 * the Free Software Foundation; either version 2 of the License, or
010 * (at your option) any later version.
011 *
012 * CleanSheets is distributed in the hope that it will be useful,
013 * but WITHOUT ANY WARRANTY; without even the implied warranty of
014 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
015 * GNU General Public License for more details.
016 *
017 * You should have received a copy of the GNU General Public License
018 * along with CleanSheets; if not, write to the Free Software
019 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
020 */
021package csheets.io;
022
023import java.io.File;
024import java.io.FilenameFilter;
025import java.util.Arrays;
026import java.util.List;
027
028/**
029 * A filename filter for filtering on filename extensions.
030 * @author Einar Pehrson
031 */
032public class FilenameExtensionFilter implements FilenameFilter {
033
034        /** The extensions of allowed files. */
035        private List<String> extensions;
036
037        /**
038         * Creates a new filter for files with the given extensions.
039         * @param extensions the extension of allowed files
040         */
041        public FilenameExtensionFilter(String... extensions) {
042                this(Arrays.asList(extensions));
043        }
044
045        /**
046         * Creates a new filter for files with the given extensions.
047         * @param extensions the extension of allowed files
048         */
049        public FilenameExtensionFilter(List<String> extensions) {
050                if (extensions.size() == 0)
051                        throw new IllegalArgumentException();
052                this.extensions = extensions;
053        }
054
055        public boolean accept(File file, String filename) {
056                String extension = filename.substring(filename.lastIndexOf('.') + 1).toLowerCase().trim();
057                return extensions.contains(extension);
058        }
059
060        /**
061         * Returns the file extensions that the filter allows.
062         * @return the file extensions that the filter allows
063         */
064        public String[] getExtensions() {
065                return extensions.toArray(new String[extensions.size()]);
066        }
067}