001 /* ===========================================================
002 * JFreeChart : a free chart library for the Java(tm) platform
003 * ===========================================================
004 *
005 * (C) Copyright 2000-2007, 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 * ArrowNeedle.java
029 * ----------------
030 * (C) Copyright 2002-2007, 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 : Added hashCode() implementation (DG);
043 *
044 */
045
046 package org.jfree.chart.needle;
047
048 import java.awt.Graphics2D;
049 import java.awt.Shape;
050 import java.awt.geom.GeneralPath;
051 import java.awt.geom.Line2D;
052 import java.awt.geom.Point2D;
053 import java.awt.geom.Rectangle2D;
054 import java.io.Serializable;
055
056 import org.jfree.chart.HashUtilities;
057
058 /**
059 * A needle in the shape of an arrow.
060 */
061 public class ArrowNeedle extends MeterNeedle
062 implements Cloneable, Serializable {
063
064 /** For serialization. */
065 private static final long serialVersionUID = -5334056511213782357L;
066
067 /**
068 * A flag controlling whether or not there is an arrow at the top of the
069 * needle.
070 */
071 private boolean isArrowAtTop = true;
072
073 /**
074 * Constructs a new arrow needle.
075 *
076 * @param isArrowAtTop a flag that controls whether or not there is an
077 * arrow at the top of the needle.
078 */
079 public ArrowNeedle(boolean isArrowAtTop) {
080 this.isArrowAtTop = isArrowAtTop;
081 }
082
083 /**
084 * Draws the needle.
085 *
086 * @param g2 the graphics device.
087 * @param plotArea the plot area.
088 * @param rotate the rotation point.
089 * @param angle the angle.
090 */
091 protected void drawNeedle(Graphics2D g2, Rectangle2D plotArea,
092 Point2D rotate, double angle) {
093
094 Line2D shape = new Line2D.Float();
095 Shape d = null;
096
097 float x = (float) (plotArea.getMinX() + (plotArea.getWidth() / 2));
098 float minY = (float) plotArea.getMinY();
099 float maxY = (float) plotArea.getMaxY();
100 shape.setLine(x, minY, x, maxY);
101
102 GeneralPath shape1 = new GeneralPath();
103 if (this.isArrowAtTop) {
104 shape1.moveTo(x, minY);
105 minY += 4 * getSize();
106 }
107 else {
108 shape1.moveTo(x, maxY);
109 minY = maxY - 4 * getSize();
110 }
111 shape1.lineTo(x + getSize(), minY);
112 shape1.lineTo(x - getSize(), minY);
113 shape1.closePath();
114
115 if ((rotate != null) && (angle != 0)) {
116 getTransform().setToRotation(angle, rotate.getX(), rotate.getY());
117 d = getTransform().createTransformedShape(shape);
118 }
119 else {
120 d = shape;
121 }
122 defaultDisplay(g2, d);
123
124 if ((rotate != null) && (angle != 0)) {
125 d = getTransform().createTransformedShape(shape1);
126 }
127 else {
128 d = shape1;
129 }
130 defaultDisplay(g2, d);
131
132 }
133
134 /**
135 * Tests another object for equality with this object.
136 *
137 * @param obj the object to test (<code>null</code> permitted).
138 *
139 * @return A boolean.
140 */
141 public boolean equals(Object obj) {
142 if (obj == this) {
143 return true;
144 }
145 if (!(obj instanceof ArrowNeedle)) {
146 return false;
147 }
148 if (!super.equals(obj)) {
149 return false;
150 }
151 ArrowNeedle that = (ArrowNeedle) obj;
152 if (this.isArrowAtTop != that.isArrowAtTop) {
153 return false;
154 }
155 return true;
156 }
157
158 /**
159 * Returns a hash code for this instance.
160 *
161 * @return A hash code.
162 */
163 public int hashCode() {
164 int result = super.hashCode();
165 result = HashUtilities.hashCode(result, this.isArrowAtTop);
166 return result;
167 }
168
169 /**
170 * Returns a clone of this needle.
171 *
172 * @return A clone.
173 *
174 * @throws CloneNotSupportedException if the <code>ArrowNeedle</code>
175 * cannot be cloned (in theory, this should not happen).
176 */
177 public Object clone() throws CloneNotSupportedException {
178 return super.clone();
179 }
180
181 }