001/* ========================================================================
002 * JCommon : a free general purpose class library for the Java(tm) platform
003 * ========================================================================
004 *
005 * (C) Copyright 2000-2005, by Object Refinery Limited and Contributors.
006 * 
007 * Project Info:  http://www.jfree.org/jcommon/index.html
008 *
009 * This library is free software; you can redistribute it and/or modify it 
010 * under the terms of the GNU Lesser General Public License as published by 
011 * the Free Software Foundation; either version 2.1 of the License, or 
012 * (at your option) any later version.
013 *
014 * This library is distributed in the hope that it will be useful, but 
015 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 
016 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public 
017 * License for more details.
018 *
019 * You should have received a copy of the GNU Lesser General Public
020 * License along with this library; if not, write to the Free Software
021 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, 
022 * USA.  
023 *
024 * [Java is a trademark or registered trademark of Sun Microsystems, Inc. 
025 * in the United States and other countries.]
026 * 
027 * ----------------------
028 * ColorWriteHandler.java
029 * ----------------------
030 * (C) Copyright 2003-2005, by Object Refinery Limited and Contributors.
031 *
032 * Original Author:  Thomas Morgner;
033 * Contributor(s):   David Gilbert (for Object Refinery Limited);
034 *
035 * $Id: ColorWriteHandler.java,v 1.3 2005/10/18 13:35:21 mungady Exp $
036 *
037 * Changes (from 23-Dec-2003)
038 * --------------------------
039 * 23-Dec-2003 : Added standard header and Javadocs (DG);
040 *
041 */
042
043package org.jfree.xml.writer.coretypes;
044
045import java.awt.Color;
046import java.io.IOException;
047
048import org.jfree.xml.writer.AbstractXmlWriteHandler;
049import org.jfree.xml.writer.AttributeList;
050import org.jfree.xml.writer.XMLWriter;
051import org.jfree.xml.writer.XMLWriterException;
052
053/**
054 * A handler for writing a {@link Color} object.
055 */
056public class ColorWriteHandler extends AbstractXmlWriteHandler  {
057
058    /**
059     * Default constructor.
060     */
061    public ColorWriteHandler() {
062        super();
063    }
064
065    /**
066     * Performs the writing of a {@link Color} object.
067     *
068     * @param tagName  the tag name.
069     * @param object  the {@link Color} object.
070     * @param writer  the writer.
071     * @param mPlexAttribute  ??.
072     * @param mPlexValue  ??.
073     * 
074     * @throws IOException if there is an I/O error.
075     * @throws XMLWriterException if there is a writer error.
076     */
077    public void write(final String tagName, final Object object, final XMLWriter writer,
078                      final String mPlexAttribute, final String mPlexValue)
079        throws IOException, XMLWriterException {
080        final Color color = (Color) object;
081        final AttributeList attribs = new AttributeList();
082        if (mPlexAttribute != null) {
083            attribs.setAttribute(mPlexAttribute, mPlexValue);
084        }
085        attribs.setAttribute("value", encodeColor(color));
086        if (color.getAlpha() != 255) {
087            attribs.setAttribute("alpha", String.valueOf(color.getAlpha()));
088        }
089        writer.writeTag(tagName, attribs, true);
090    }
091
092    private String encodeColor(final Color color) {
093        return "#" + encodeInt(color.getRed()) 
094            + encodeInt(color.getGreen()) + encodeInt(color.getBlue());
095    }
096
097    private String encodeInt(final int i) {
098        final String retVal = Integer.toHexString(i);
099        if (retVal.length() == 1) {
100            return "0" + retVal;
101        } 
102        else {
103            return retVal;
104        }
105    }
106}