001 /* ===========================================================
002 * JFreeChart : a free chart library for the Java(tm) platform
003 * ===========================================================
004 *
005 * (C) Copyright 2000-2006, 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 * PlumNeedle.java
029 * ---------------
030 * (C) Copyright 2002-2006, by the Australian Antarctic Division and
031 * Contributors.
032 *
033 * Original Author: Bryan Scott (for the Australian Antarctic Division);
034 * Contributor(s): David Gilbert (for Object Refinery Limited);
035 *
036 * $Id: PlumNeedle.java,v 1.4.2.3 2006/08/02 10:40:57 mungady Exp $
037 *
038 * Changes:
039 * --------
040 * 25-Sep-2002 : Version 1, contributed by Bryan Scott (DG);
041 * 27-Mar-2003 : Implemented Serializable (DG);
042 * 09-Sep-2003 : Added equals() method (DG);
043 * 08-Jun-2005 : Implemented Cloneable (DG);
044 *
045 */
046
047 package org.jfree.chart.needle;
048
049 import java.awt.Graphics2D;
050 import java.awt.geom.Arc2D;
051 import java.awt.geom.Area;
052 import java.awt.geom.Point2D;
053 import java.awt.geom.Rectangle2D;
054 import java.io.Serializable;
055
056 /**
057 * A needle for use with the {@link org.jfree.chart.plot.CompassPlot} class.
058 */
059 public class PlumNeedle extends MeterNeedle
060 implements Cloneable, Serializable {
061
062 /** For serialization. */
063 private static final long serialVersionUID = -3082660488660600718L;
064
065 /**
066 * Draws the needle.
067 *
068 * @param g2 the graphics device.
069 * @param plotArea the plot area.
070 * @param rotate the rotation point.
071 * @param angle the angle.
072 */
073 protected void drawNeedle(Graphics2D g2, Rectangle2D plotArea,
074 Point2D rotate, double angle) {
075
076 Arc2D shape = new Arc2D.Double(Arc2D.PIE);
077 double radius = plotArea.getHeight();
078 double halfX = plotArea.getWidth() / 2;
079 double diameter = 2 * radius;
080
081 shape.setFrame(plotArea.getMinX() + halfX - radius ,
082 plotArea.getMinY() - radius,
083 diameter, diameter);
084 radius = Math.toDegrees(Math.asin(halfX / radius));
085 shape.setAngleStart(270 - radius);
086 shape.setAngleExtent(2 * radius);
087
088 Area s = new Area(shape);
089
090 if ((rotate != null) && (angle != 0)) {
091 /// we have rotation houston, please spin me
092 getTransform().setToRotation(angle, rotate.getX(), rotate.getY());
093 s.transform(getTransform());
094 }
095
096 defaultDisplay(g2, s);
097 }
098
099 /**
100 * Tests another object for equality with this object.
101 *
102 * @param obj the object to test (<code>null</code> permitted).
103 *
104 * @return A boolean.
105 */
106 public boolean equals(Object obj) {
107 if (obj == this) {
108 return true;
109 }
110 if (!(obj instanceof PlumNeedle)) {
111 return false;
112 }
113 if (!super.equals(obj)) {
114 return false;
115 }
116 return true;
117 }
118
119 /**
120 * Returns a clone of this needle.
121 *
122 * @return A clone.
123 *
124 * @throws CloneNotSupportedException if the <code>PlumNeedle</code>
125 * cannot be cloned (in theory, this should not happen).
126 */
127 public Object clone() throws CloneNotSupportedException {
128 return super.clone();
129 }
130
131 }