001/* ===========================================================
002 * JFreeChart : a free chart library for the Java(tm) platform
003 * ===========================================================
004 *
005 * (C) Copyright 2000-2013, 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 * [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 * ArrowNeedle.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 : Added hashCode() implementation (DG);
043 *
044 */
045
046package org.jfree.chart.needle;
047
048import java.awt.Graphics2D;
049import java.awt.Shape;
050import java.awt.geom.GeneralPath;
051import java.awt.geom.Line2D;
052import java.awt.geom.Point2D;
053import java.awt.geom.Rectangle2D;
054import java.io.Serializable;
055
056import org.jfree.chart.HashUtilities;
057
058/**
059 * A needle in the shape of an arrow.
060 */
061public 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    @Override
092    protected void drawNeedle(Graphics2D g2, Rectangle2D plotArea,
093                              Point2D rotate, double angle) {
094
095        Line2D shape = new Line2D.Float();
096        Shape d;
097
098        float x = (float) (plotArea.getMinX() +  (plotArea.getWidth() / 2));
099        float minY = (float) plotArea.getMinY();
100        float maxY = (float) plotArea.getMaxY();
101        shape.setLine(x, minY, x, maxY);
102
103        GeneralPath shape1 = new GeneralPath();
104        if (this.isArrowAtTop) {
105            shape1.moveTo(x, minY);
106            minY += 4 * getSize();
107        }
108        else {
109            shape1.moveTo(x, maxY);
110            minY = maxY - 4 * getSize();
111        }
112        shape1.lineTo(x + getSize(), minY);
113        shape1.lineTo(x - getSize(), minY);
114        shape1.closePath();
115
116        if ((rotate != null) && (angle != 0)) {
117            getTransform().setToRotation(angle, rotate.getX(), rotate.getY());
118            d = getTransform().createTransformedShape(shape);
119        }
120        else {
121            d = shape;
122        }
123        defaultDisplay(g2, d);
124
125        if ((rotate != null) && (angle != 0)) {
126            d = getTransform().createTransformedShape(shape1);
127        }
128        else {
129            d = shape1;
130        }
131        defaultDisplay(g2, d);
132
133    }
134
135    /**
136     * Tests another object for equality with this object.
137     *
138     * @param obj  the object to test (<code>null</code> permitted).
139     *
140     * @return A boolean.
141     */
142    @Override
143    public boolean equals(Object obj) {
144        if (obj == this) {
145            return true;
146        }
147        if (!(obj instanceof ArrowNeedle)) {
148            return false;
149        }
150        if (!super.equals(obj)) {
151            return false;
152        }
153        ArrowNeedle that = (ArrowNeedle) obj;
154        if (this.isArrowAtTop != that.isArrowAtTop) {
155            return false;
156        }
157        return true;
158    }
159
160    /**
161     * Returns a hash code for this instance.
162     *
163     * @return A hash code.
164     */
165    @Override
166    public int hashCode() {
167        int result = super.hashCode();
168        result = HashUtilities.hashCode(result, this.isArrowAtTop);
169        return result;
170    }
171
172    /**
173     * Returns a clone of this needle.
174     *
175     * @return A clone.
176     *
177     * @throws CloneNotSupportedException if the <code>ArrowNeedle</code>
178     *     cannot be cloned (in theory, this should not happen).
179     */
180    @Override
181    public Object clone() throws CloneNotSupportedException {
182        return super.clone();
183    }
184
185}