001    /* ===========================================================
002     * JFreeChart : a free chart library for the Java(tm) platform
003     * ===========================================================
004     *
005     * (C) Copyright 2000-2007, by Object Refinery Limited and Contributors.
006     *
007     * Project Info:  http://www.jfree.org/jfreechart/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     * ColorBlock.java
029     * ---------------
030     * (C) Copyright 2004, 2007, by Object Refinery Limited.
031     *
032     * Original Author:  David Gilbert (for Object Refinery Limited);
033     * Contributor(s):   -;
034     *
035     * $Id: ColorBlock.java,v 1.4.2.2 2007/03/16 15:26:15 mungady Exp $
036     *
037     * Changes:
038     * --------
039     * 22-Oct-2004 : Version 1 (DG);
040     * 20-Apr-2005 : Added new draw() method (DG);
041     * ------------- JFREECHART 1.0.x ---------------------------------------------
042     * 16-Mar-2007 : Implemented equals() and fixed serialization (DG);
043     * 
044     */
045    
046    package org.jfree.chart.block;
047    
048    import java.awt.Graphics2D;
049    import java.awt.Paint;
050    import java.awt.geom.Rectangle2D;
051    import java.io.IOException;
052    import java.io.ObjectInputStream;
053    import java.io.ObjectOutputStream;
054    
055    import org.jfree.io.SerialUtilities;
056    import org.jfree.util.PaintUtilities;
057    
058    /**
059     * A block that is filled with a single color.
060     */
061    public class ColorBlock extends AbstractBlock implements Block {
062    
063        /** The paint. */
064        private transient Paint paint;
065        
066        /**
067         * Creates a new block.
068         * 
069         * @param paint  the paint (<code>null</code> not permitted).
070         * @param width  the width.
071         * @param height  the height.
072         */
073        public ColorBlock(Paint paint, double width, double height) {
074            if (paint == null) {
075                throw new IllegalArgumentException("Null 'paint' argument.");
076            }
077            this.paint = paint;
078            setWidth(width);
079            setHeight(height);
080        }
081    
082        /**
083         * Returns the paint.
084         * 
085         * @return The paint (never <code>null</code>).
086         * 
087         * @since 1.0.5
088         */
089        public Paint getPaint() {
090            return this.paint;
091        }
092        
093        /**
094         * Draws the block.
095         * 
096         * @param g2  the graphics device.
097         * @param area  the area.
098         */
099        public void draw(Graphics2D g2, Rectangle2D area) {
100            Rectangle2D bounds = getBounds();
101            g2.setPaint(this.paint);
102            g2.fill(bounds);
103        }
104        
105        /**
106         * Draws the block within the specified area.
107         * 
108         * @param g2  the graphics device.
109         * @param area  the area.
110         * @param params  ignored (<code>null</code> permitted).
111         * 
112         * @return Always <code>null</code>.
113         */
114        public Object draw(Graphics2D g2, Rectangle2D area, Object params) {
115            draw(g2, area);
116            return null;
117        }
118        
119        /**
120         * Tests this block for equality with an arbitrary object.
121         * 
122         * @param obj  the object (<code>null</code> permitted).
123         * 
124         * @return A boolean.
125         */
126        public boolean equals(Object obj) {
127            if (obj == this) {
128                return true;
129            }
130            if (!(obj instanceof ColorBlock)) {
131                return false;
132            }
133            ColorBlock that = (ColorBlock) obj;
134            if (!PaintUtilities.equal(this.paint, that.paint)) {
135                return false;
136            }
137            return super.equals(obj);
138        }
139        
140        /**
141         * Provides serialization support.
142         *
143         * @param stream  the output stream.
144         *
145         * @throws IOException if there is an I/O error.
146         */
147        private void writeObject(ObjectOutputStream stream) throws IOException {
148            stream.defaultWriteObject();
149            SerialUtilities.writePaint(this.paint, stream);
150        }
151    
152        /**
153         * Provides serialization support.
154         *
155         * @param stream  the input stream.
156         *
157         * @throws IOException  if there is an I/O error.
158         * @throws ClassNotFoundException  if there is a classpath problem.
159         */
160        private void readObject(ObjectInputStream stream) 
161            throws IOException, ClassNotFoundException {
162            stream.defaultReadObject();
163            this.paint = SerialUtilities.readPaint(stream);
164        }
165    
166    }