001/*
002 * $Id: IconValues.java 3927 2011-02-22 16:34:11Z kleopatra $
003 *
004 * Copyright 2008 Sun Microsystems, Inc., 4150 Network Circle,
005 * Santa Clara, California 95054, U.S.A. All rights reserved.
006 *
007 * This library is free software; you can redistribute it and/or
008 * modify it under the terms of the GNU Lesser General Public
009 * License as published by the Free Software Foundation; either
010 * version 2.1 of the License, or (at your option) any later version.
011 * 
012 * This library 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 GNU
015 * Lesser General Public License for more details.
016 * 
017 * You should have received a copy of the GNU Lesser General Public
018 * License along with this library; if not, write to the Free Software
019 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
020 */
021package org.jdesktop.swingx.renderer;
022
023import java.io.File;
024
025import javax.swing.Icon;
026import javax.swing.filechooser.FileSystemView;
027
028/**
029 * A collection of common {@code IconValue} implementations.
030 * 
031 * @author Karl George Schaefer
032 * @author Jeanette Winzenburg
033 */
034public final class IconValues {
035    /**
036     * Always NULL_ICON. This is useful to indicate that we really want
037     * no icon instead of f.i. a default provided by the CellContext. 
038     */
039    @SuppressWarnings("serial")
040    public static final IconValue NONE = new IconValue() {
041    
042        @Override
043        public Icon getIcon(Object value) {
044            return IconValue.NULL_ICON;
045        }
046        
047    };
048
049    /**
050     * Returns the value as Icon if possible or null.
051     */
052    @SuppressWarnings("serial")
053    public static final IconValue ICON = new IconValue() {
054    
055        @Override
056        public Icon getIcon(Object value) {
057            if (value instanceof Icon) {
058                return (Icon) value;
059            }
060            return null;
061        }
062    };
063    
064    /**
065     * An {@code IconValue} that presents the current L&F icon for a given file.
066     * If the value passed to {@code FILE_ICON} is not a {@link File}, this has
067     * the same effect as {@link IconValues#NONE}.
068     */
069    @SuppressWarnings("serial")
070    public static final IconValue FILE_ICON = new IconValue() {
071        @Override
072        public Icon getIcon(Object value) {
073            if (value instanceof File) {
074                FileSystemView fsv = FileSystemView.getFileSystemView();
075
076                return fsv.getSystemIcon((File) value);
077            }
078
079            return IconValues.NONE.getIcon(value);
080        }
081    };
082    
083    private IconValues() {
084        // does nothing
085    }
086}