    001    /* ===========================================================
    002     * JFreeChart : a free chart library for the Java(tm) platform
    003     * ===========================================================
    004     *
    005     * (C) Copyright 2000-2008, 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     * DialBackground.java
    029     * -------------------
    030     * (C) Copyright 2006-2008, by Object Refinery Limited.
    031     *
    032     * Original Author:  David Gilbert (for Object Refinery Limited);
    033     * Contributor(s):   -;
    034     *
    035     * Changes
    036     * -------
    037     * 03-Nov-2006 : Version 1 (DG);
    038     * 16-Oct-2007 : The equals() method needs to call super.equals() (DG);
    039     *
    040     */
    041
    042    package org.jfree.chart.plot.dial;
    043
    044    import java.awt.Color;
    045    import java.awt.GradientPaint;
    046    import java.awt.Graphics2D;
    047    import java.awt.Paint;
    048    import java.awt.geom.Rectangle2D;
    049    import java.io.IOException;
    050    import java.io.ObjectInputStream;
    051    import java.io.ObjectOutputStream;
    052    import java.io.Serializable;
    053
    054    import org.jfree.chart.HashUtilities;
    055    import org.jfree.io.SerialUtilities;
    056    import org.jfree.ui.GradientPaintTransformer;
    057    import org.jfree.ui.StandardGradientPaintTransformer;
    058    import org.jfree.util.PaintUtilities;
    059    import org.jfree.util.PublicCloneable;
    060
    061    /**
    062     * A regular dial layer that can be used to draw the background for a dial.
    063     *
    064     * @since 1.0.7
    065     */
    066    public class DialBackground extends AbstractDialLayer implements DialLayer,
    067            Cloneable, PublicCloneable, Serializable {
    068
    069        /** For serialization. */
    070        static final long serialVersionUID = -9019069533317612375L;
    071
    072        /**
    073         * The background paint.  This field is transient because serialization
    074         * requires special handling.
    075         */
    076        private transient Paint paint;
    077
    078        /**
    079         * The transformer used when the background paint is an instance of
    080         * <code>GradientPaint</code>.
    081         */
    082        private GradientPaintTransformer gradientPaintTransformer;
    083
    084        /**
    085         * Creates a new instance of <code>DialBackground</code>.  The
    086         * default background paint is <code>Color.white</code>.
    087         */
    088        public DialBackground() {
    089            this(Color.white);
    090        }
    091
    092        /**
    093         * Creates a new instance of <code>DialBackground</code>.  The
    094         *
    095         * @param paint  the paint (<code>null</code> not permitted).
    096         *
    097         * @throws IllegalArgumentException if <code>paint</code> is
    098         *     <code>null</code>.
    099         */
    100        public DialBackground(Paint paint) {
    101            if (paint == null) {
    102                throw new IllegalArgumentException("Null 'paint' argument.");
    103            }
    104            this.paint = paint;
    105            this.gradientPaintTransformer = new StandardGradientPaintTransformer();
    106        }
    107
    108        /**
    109         * Returns the paint used to fill the background.
    110         *
    111         * @return The paint (never <code>null</code>).
    112         *
    113         * @see #setPaint(Paint)
    114         */
    115        public Paint getPaint() {
    116            return this.paint;
    117        }
    118
    119        /**
    120         * Sets the paint for the dial background and sends a
    121         * {@link DialLayerChangeEvent} to all registered listeners.
    122         *
    123         * @param paint  the paint (<code>null</code> not permitted).
    124         *
    125         * @see #getPaint()
    126         */
    127        public void setPaint(Paint paint) {
    128            if (paint == null) {
    129                throw new IllegalArgumentException("Null 'paint' argument.");
    130            }
    131            this.paint = paint;
    132            notifyListeners(new DialLayerChangeEvent(this));
    133        }
    134
    135        /**
    136         * Returns the transformer used to adjust the coordinates of any
    137         * <code>GradientPaint</code> instance used for the background paint.
    138         *
    139         * @return The transformer (never <code>null</code>).
    140         *
    141         * @see #setGradientPaintTransformer(GradientPaintTransformer)
    142         */
    143        public GradientPaintTransformer getGradientPaintTransformer() {
    144            return this.gradientPaintTransformer;
    145        }
    146
    147        /**
    148         * Sets the transformer used to adjust the coordinates of any
    149         * <code>GradientPaint</code> instance used for the background paint, and
    150         * sends a {@link DialLayerChangeEvent} to all registered listeners.
    151         *
    152         * @param t  the transformer (<code>null</code> not permitted).
    153         *
    154         * @see #getGradientPaintTransformer()
    155         */
    156        public void setGradientPaintTransformer(GradientPaintTransformer t) {
    157            if (t == null) {
    158                throw new IllegalArgumentException("Null 't' argument.");
    159            }
    160            this.gradientPaintTransformer = t;
    161            notifyListeners(new DialLayerChangeEvent(this));
    162        }
    163
    164        /**
    165         * Returns <code>true</code> to indicate that this layer should be
    166         * clipped within the dial window.
    167         *
    168         * @return <code>true</code>.
    169         */
    170        public boolean isClippedToWindow() {
    171            return true;
    172        }
    173
    174        /**
    175         * Draws the background to the specified graphics device.  If the dial
    176         * frame specifies a window, the clipping region will already have been
    177         * set to this window before this method is called.
    178         *
    179         * @param g2  the graphics device (<code>null</code> not permitted).
    180         * @param plot  the plot (ignored here).
    181         * @param frame  the dial frame (ignored here).
    182         * @param view  the view rectangle (<code>null</code> not permitted).
    183         */
    184        public void draw(Graphics2D g2, DialPlot plot, Rectangle2D frame,
    185                Rectangle2D view) {
    186
    187            Paint p = this.paint;
    188            if (p instanceof GradientPaint) {
    189                p = this.gradientPaintTransformer.transform((GradientPaint) p,
    190                        view);
    191            }
    192            g2.setPaint(p);
    193            g2.fill(view);
    194        }
    195
    196        /**
    197         * Tests this instance for equality with an arbitrary object.
    198         *
    199         * @param obj  the object (<code>null</code> permitted).
    200         *
    201         * @return A boolean.
    202         */
    203        public boolean equals(Object obj) {
    204            if (obj == this) {
    205                return true;
    206            }
    207            if (!(obj instanceof DialBackground)) {
    208                return false;
    209            }
    210            DialBackground that = (DialBackground) obj;
    211            if (!PaintUtilities.equal(this.paint, that.paint)) {
    212                return false;
    213            }
    214            if (!this.gradientPaintTransformer.equals(
    215                    that.gradientPaintTransformer)) {
    216                return false;
    217            }
    218            return super.equals(obj);
    219        }
    220
    221        /**
    222         * Returns a hash code for this instance.
    223         *
    224         * @return The hash code.
    225         */
    226        public int hashCode() {
    227            int result = 193;
    228            result = 37 * result + HashUtilities.hashCodeForPaint(this.paint);
    229            result = 37 * result + this.gradientPaintTransformer.hashCode();
    230            return result;
    231        }
    232
    233        /**
    234         * Returns a clone of this instance.
    235         *
    236         * @return The clone.
    237         *
    238         * @throws CloneNotSupportedException if some attribute of this instance
    239         *     cannot be cloned.
    240         */
    241        public Object clone() throws CloneNotSupportedException {
    242            return super.clone();
    243        }
    244
    245        /**
    246         * Provides serialization support.
    247         *
    248         * @param stream  the output stream.
    249         *
    250         * @throws IOException  if there is an I/O error.
    251         */
    252        private void writeObject(ObjectOutputStream stream) throws IOException {
    253            stream.defaultWriteObject();
    254            SerialUtilities.writePaint(this.paint, stream);
    255        }
    256
    257        /**
    258         * Provides serialization support.
    259         *
    260         * @param stream  the input stream.
    261         *
    262         * @throws IOException  if there is an I/O error.
    263         * @throws ClassNotFoundException  if there is a classpath problem.
    264         */
    265        private void readObject(ObjectInputStream stream)
    266                throws IOException, ClassNotFoundException {
    267            stream.defaultReadObject();
    268            this.paint = SerialUtilities.readPaint(stream);
    269        }
    270
    271    }