001/* ======================================================
002 * JFreeChart : a chart library for the Java(tm) platform
003 * ======================================================
004 *
005 * (C) Copyright 2000-present, by David Gilbert and Contributors.
006 *
007 * Project Info:  https://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 * PlumNeedle.java
029 * ---------------
030 * (C) Copyright 2002-present, by the Australian Antarctic Division and
031 *                          Contributors.
032 *
033 * Original Author:  Bryan Scott (for the Australian Antarctic Division);
034 * Contributor(s):   David Gilbert;
035 *
036 */
037
038package org.jfree.chart.needle;
039
040import java.awt.Graphics2D;
041import java.awt.geom.Arc2D;
042import java.awt.geom.Area;
043import java.awt.geom.Point2D;
044import java.awt.geom.Rectangle2D;
045import java.io.Serializable;
046
047/**
048 * A needle for use with the {@link org.jfree.chart.plot.CompassPlot} class.
049 */
050public class PlumNeedle extends MeterNeedle implements Cloneable, Serializable {
051
052    /** For serialization. */
053    private static final long serialVersionUID = -3082660488660600718L;
054
055    /**
056     * Creates a new instance.
057     */
058    public PlumNeedle() {
059        super();
060    }
061
062    /**
063     * Draws the needle.
064     *
065     * @param g2  the graphics device.
066     * @param plotArea  the plot area.
067     * @param rotate  the rotation point.
068     * @param angle  the angle.
069     */
070    @Override
071    protected void drawNeedle(Graphics2D g2, Rectangle2D plotArea,
072            Point2D rotate, double angle) {
073
074        Arc2D shape = new Arc2D.Double(Arc2D.PIE);
075        double radius = plotArea.getHeight();
076        double halfX = plotArea.getWidth() / 2;
077        double diameter = 2 * radius;
078
079        shape.setFrame(plotArea.getMinX() + halfX - radius,
080                       plotArea.getMinY() - radius,
081                       diameter, diameter);
082        radius = Math.toDegrees(Math.asin(halfX / radius));
083        shape.setAngleStart(270 - radius);
084        shape.setAngleExtent(2 * radius);
085
086        Area s = new Area(shape);
087
088        if ((rotate != null) && (angle != 0)) {
089            /// we have rotation houston, please spin me
090            getTransform().setToRotation(angle, rotate.getX(), rotate.getY());
091            s.transform(getTransform());
092        }
093
094        defaultDisplay(g2, s);
095    }
096
097    /**
098     * Tests another object for equality with this object.
099     *
100     * @param obj  the object to test ({@code null} permitted).
101     *
102     * @return A boolean.
103     */
104    @Override
105    public boolean equals(Object obj) {
106        if (obj == this) {
107            return true;
108        }
109        if (!(obj instanceof PlumNeedle)) {
110            return false;
111        }
112        if (!super.equals(obj)) {
113            return false;
114        }
115        return true;
116    }
117
118    /**
119     * Returns a hash code for this instance.
120     *
121     * @return A hash code.
122     */
123    @Override
124    public int hashCode() {
125        return super.hashCode();
126    }
127
128    /**
129     * Returns a clone of this needle.
130     *
131     * @return A clone.
132     *
133     * @throws CloneNotSupportedException if the {@code PlumNeedle}
134     *     cannot be cloned (in theory, this should not happen).
135     */
136    @Override
137    public Object clone() throws CloneNotSupportedException {
138        return super.clone();
139    }
140
141}