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 * PlumNeedle.java
029 * ---------------
030 * (C) Copyright 2002-2008, 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 * Changes:
037 * --------
038 * 25-Sep-2002 : Version 1, contributed by Bryan Scott (DG);
039 * 27-Mar-2003 : Implemented Serializable (DG);
040 * 09-Sep-2003 : Added equals() method (DG);
041 * 08-Jun-2005 : Implemented Cloneable (DG);
042 * 22-Nov-2007 : Implemented hashCode() (DG);
043 *
044 */
045
046 package org.jfree.chart.needle;
047
048 import java.awt.Graphics2D;
049 import java.awt.geom.Arc2D;
050 import java.awt.geom.Area;
051 import java.awt.geom.Point2D;
052 import java.awt.geom.Rectangle2D;
053 import java.io.Serializable;
054
055 /**
056 * A needle for use with the {@link org.jfree.chart.plot.CompassPlot} class.
057 */
058 public class PlumNeedle extends MeterNeedle
059 implements Cloneable, Serializable {
060
061 /** For serialization. */
062 private static final long serialVersionUID = -3082660488660600718L;
063
064 /**
065 * Draws the needle.
066 *
067 * @param g2 the graphics device.
068 * @param plotArea the plot area.
069 * @param rotate the rotation point.
070 * @param angle the angle.
071 */
072 protected void drawNeedle(Graphics2D g2, Rectangle2D plotArea,
073 Point2D rotate, double angle) {
074
075 Arc2D shape = new Arc2D.Double(Arc2D.PIE);
076 double radius = plotArea.getHeight();
077 double halfX = plotArea.getWidth() / 2;
078 double diameter = 2 * radius;
079
080 shape.setFrame(plotArea.getMinX() + halfX - radius ,
081 plotArea.getMinY() - radius,
082 diameter, diameter);
083 radius = Math.toDegrees(Math.asin(halfX / radius));
084 shape.setAngleStart(270 - radius);
085 shape.setAngleExtent(2 * radius);
086
087 Area s = new Area(shape);
088
089 if ((rotate != null) && (angle != 0)) {
090 /// we have rotation houston, please spin me
091 getTransform().setToRotation(angle, rotate.getX(), rotate.getY());
092 s.transform(getTransform());
093 }
094
095 defaultDisplay(g2, s);
096 }
097
098 /**
099 * Tests another object for equality with this object.
100 *
101 * @param obj the object to test (<code>null</code> permitted).
102 *
103 * @return A boolean.
104 */
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 public int hashCode() {
124 return super.hashCode();
125 }
126
127 /**
128 * Returns a clone of this needle.
129 *
130 * @return A clone.
131 *
132 * @throws CloneNotSupportedException if the <code>PlumNeedle</code>
133 * cannot be cloned (in theory, this should not happen).
134 */
135 public Object clone() throws CloneNotSupportedException {
136 return super.clone();
137 }
138
139 }