ImageFilter.java

/***
 * Copyright (c) 2008, Endless Loop Software, Inc.
 * 
 * This file is part of EgoNet.
 * 
 * EgoNet is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 3 of the License, or
 * (at your option) any later version.
 * 
 * EgoNet is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package org.egonet.util;

import java.io.File;
import java.util.HashSet;
import java.util.Set;

import javax.imageio.ImageIO;
import javax.swing.filechooser.*;

public class ImageFilter extends FileFilter {
    
    Set<String> extensionNames;
    public ImageFilter()
    {
        String [] formats = ImageIO.getWriterFormatNames();
        extensionNames = new HashSet<String>(formats.length);
        
        for(String fmt : formats)
            extensionNames.add(fmt.toLowerCase());
    }

    //Accept all directories and all gif, jpg, tiff, or png files.
    public boolean accept(File f) {
        if (f.isDirectory()) {
            return true;
        }

        String extension = getExtension(f);
        return (extension != null && extensionNames.contains(extension.toLowerCase()));
    }

    public static String getExtension(File f) {
        String ext = null;
        String s = f.getName();
        int i = s.lastIndexOf('.');

        if (i > 0 &&  i < s.length() - 1) {
            ext = s.substring(i+1).toLowerCase();
        }
        return ext;
    }
    //The description of this filter
    public String getDescription() {
        return "Image formats " + extensionNames.toString();
    }
}