Source for org.jfree.chart.needle.PointerNeedle

   1: /* ===========================================================
   2:  * JFreeChart : a free chart library for the Java(tm) platform
   3:  * ===========================================================
   4:  *
   5:  * (C) Copyright 2000-2007, by Object Refinery Limited and Contributors.
   6:  *
   7:  * Project Info:  http://www.jfree.org/jfreechart/index.html
   8:  *
   9:  * This library is free software; you can redistribute it and/or modify it 
  10:  * under the terms of the GNU Lesser General Public License as published by 
  11:  * the Free Software Foundation; either version 2.1 of the License, or 
  12:  * (at your option) any later version.
  13:  *
  14:  * This library is distributed in the hope that it will be useful, but 
  15:  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 
  16:  * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public 
  17:  * License for more details.
  18:  *
  19:  * You should have received a copy of the GNU Lesser General Public
  20:  * License along with this library; if not, write to the Free Software
  21:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, 
  22:  * USA.  
  23:  *
  24:  * [Java is a trademark or registered trademark of Sun Microsystems, Inc. 
  25:  * in the United States and other countries.]
  26:  *
  27:  * ------------------
  28:  * PointerNeedle.java
  29:  * ------------------
  30:  * (C) Copyright 2002-2007, by the Australian Antarctic Division and 
  31:  *                          Contributors.
  32:  *
  33:  * Original Author:  Bryan Scott (for the Australian Antarctic Division);
  34:  * Contributor(s):   David Gilbert (for Object Refinery Limited);
  35:  *
  36:  * Changes:
  37:  * --------
  38:  * 25-Sep-2002 : Version 1, contributed by Bryan Scott (DG);
  39:  * 26-Mar-2003 : Implemented Serializable (DG);
  40:  * 09-Sep-2003 : Added equals() method (DG);
  41:  * 08-Jun-2005 : Implemented Cloneable (DG);
  42:  * 22-Nov-2007 : Implemented hashCode() (DG);
  43:  *
  44:  */
  45: 
  46: package org.jfree.chart.needle;
  47: 
  48: import java.awt.Graphics2D;
  49: import java.awt.geom.GeneralPath;
  50: import java.awt.geom.Point2D;
  51: import java.awt.geom.Rectangle2D;
  52: import java.io.Serializable;
  53: 
  54: /**
  55:  * A needle in the shape of a pointer, for use with the
  56:  * {@link org.jfree.chart.plot.CompassPlot} class.
  57:  */
  58: public class PointerNeedle extends MeterNeedle 
  59:                            implements Cloneable, Serializable {
  60: 
  61:     /** For serialization. */
  62:     private static final long serialVersionUID = -4744677345334729606L;
  63:     
  64:     /**
  65:      * Draws the needle.
  66:      *
  67:      * @param g2  the graphics device.
  68:      * @param plotArea  the plot area.
  69:      * @param rotate  the rotation point.
  70:      * @param angle  the angle.
  71:      */
  72:     protected void drawNeedle(Graphics2D g2, Rectangle2D plotArea, 
  73:                               Point2D rotate, double angle) {
  74: 
  75:         GeneralPath shape1 = new GeneralPath();
  76:         GeneralPath shape2 = new GeneralPath();
  77:         float minX = (float) plotArea.getMinX();
  78:         float minY = (float) plotArea.getMinY();
  79:         float maxX = (float) plotArea.getMaxX();
  80:         float maxY = (float) plotArea.getMaxY();
  81:         float midX = (float) (minX + (plotArea.getWidth() / 2));
  82:         float midY = (float) (minY + (plotArea.getHeight() / 2));
  83: 
  84:         shape1.moveTo(minX, midY);
  85:         shape1.lineTo(midX, minY);
  86:         shape1.lineTo(maxX, midY);
  87:         shape1.closePath();
  88: 
  89:         shape2.moveTo(minX, midY);
  90:         shape2.lineTo(midX, maxY);
  91:         shape2.lineTo(maxX, midY);
  92:         shape2.closePath();
  93: 
  94:         if ((rotate != null) && (angle != 0)) {
  95:             /// we have rotation huston, please spin me
  96:             getTransform().setToRotation(angle, rotate.getX(), rotate.getY());
  97:             shape1.transform(getTransform());
  98:             shape2.transform(getTransform());
  99:         }
 100: 
 101:         if (getFillPaint() != null) {
 102:             g2.setPaint(getFillPaint());
 103:             g2.fill(shape1);
 104:         }
 105: 
 106:         if (getHighlightPaint() != null) {
 107:             g2.setPaint(getHighlightPaint());
 108:             g2.fill(shape2);
 109:         }
 110: 
 111:         if (getOutlinePaint() != null) {
 112:             g2.setStroke(getOutlineStroke());
 113:             g2.setPaint(getOutlinePaint());
 114:             g2.draw(shape1);
 115:             g2.draw(shape2);
 116:         }
 117:     }
 118: 
 119:     /**
 120:      * Tests another object for equality with this object.
 121:      * 
 122:      * @param obj  the object to test (<code>null</code> permitted).
 123:      * 
 124:      * @return A boolean.
 125:      */
 126:     public boolean equals(Object obj) {
 127:         if (obj == this) {
 128:             return true;
 129:         }
 130:         if (!(obj instanceof PointerNeedle)) {
 131:             return false;   
 132:         }
 133:         if (!super.equals(obj)) {
 134:             return false;
 135:         }
 136:         return true;
 137:     }
 138: 
 139:     /**
 140:      * Returns a hash code for this instance.
 141:      * 
 142:      * @return A hash code.
 143:      */
 144:     public int hashCode() {
 145:         return super.hashCode();
 146:     }
 147: 
 148:     /**
 149:      * Returns a clone of this needle.
 150:      * 
 151:      * @return A clone.
 152:      * 
 153:      * @throws CloneNotSupportedException if the <code>PointerNeedle</code> 
 154:      *     cannot be cloned (in theory, this should not happen).
 155:      */
 156:     public Object clone() throws CloneNotSupportedException {
 157:         return super.clone();   
 158:     }
 159: 
 160: }