    001/* ===========================================================
    002 * JFreeChart : a free chart library for the Java(tm) platform
    003 * ===========================================================
    004 *
    005 * (C) Copyright 2000-2011, 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 * [Oracle and Java are registered trademarks of Oracle and/or its affiliates.
    025 * Other names may be trademarks of their respective owners.]
    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
    042package org.jfree.chart.plot.dial;
    043
    044import java.awt.Color;
    045import java.awt.GradientPaint;
    046import java.awt.Graphics2D;
    047import java.awt.Paint;
    048import java.awt.geom.Rectangle2D;
    049import java.io.IOException;
    050import java.io.ObjectInputStream;
    051import java.io.ObjectOutputStream;
    052import java.io.Serializable;
    053
    054import org.jfree.chart.HashUtilities;
    055import org.jfree.io.SerialUtilities;
    056import org.jfree.ui.GradientPaintTransformer;
    057import org.jfree.ui.StandardGradientPaintTransformer;
    058import org.jfree.util.PaintUtilities;
    059import 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 */
    066public 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}