001/* ========================================================================
002 * JCommon : a free general purpose class library for the Java(tm) platform
003 * ========================================================================
004 *
005 * (C) Copyright 2000-2005, by Object Refinery Limited and Contributors.
006 * 
007 * Project Info:  http://www.jfree.org/jcommon/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 * RectangleAnchor.java
029 * --------------------
030 * (C) Copyright 2003-2005, by Object Refinery Limited.
031 *
032 * Original Author:  David Gilbert (for Object Refinery Limited);
033 * Contributor(s):   -;
034 *
035 * $Id: RectangleAnchor.java,v 1.6 2005/10/18 13:18:34 mungady Exp $
036 *
037 * Changes:
038 * --------
039 * 31-Oct-2003 (DG);
040 * 01-Apr-2004 : Changed java.awt.geom.Dimension2D to org.jfree.ui.Size2D 
041 *               because of JDK bug 4976448 which persists on JDK 1.3.1 (DG);
042 * 21-Jan-2005 : Changed return type of coordinates() method (DG);
043 * 
044 */
045
046package org.jfree.ui;
047
048import java.awt.geom.Point2D;
049import java.awt.geom.Rectangle2D;
050import java.io.ObjectStreamException;
051import java.io.Serializable;
052
053/**
054 * Used to indicate an anchor point for a rectangle.
055 *
056 * @author David Gilbert
057 */
058public final class RectangleAnchor implements Serializable {
059
060    /** For serialization. */
061    private static final long serialVersionUID = -2457494205644416327L;
062    
063    /** Center. */
064    public static final RectangleAnchor CENTER 
065        = new RectangleAnchor("RectangleAnchor.CENTER");
066
067    /** Top. */
068    public static final RectangleAnchor TOP 
069        = new RectangleAnchor("RectangleAnchor.TOP");
070
071    /** Top-Left. */
072    public static final RectangleAnchor TOP_LEFT 
073        = new RectangleAnchor("RectangleAnchor.TOP_LEFT");
074
075    /** Top-Right. */
076    public static final RectangleAnchor TOP_RIGHT 
077        = new RectangleAnchor("RectangleAnchor.TOP_RIGHT");
078
079    /** Bottom. */
080    public static final RectangleAnchor BOTTOM 
081        = new RectangleAnchor("RectangleAnchor.BOTTOM");
082
083    /** Bottom-Left. */
084    public static final RectangleAnchor BOTTOM_LEFT 
085        = new RectangleAnchor("RectangleAnchor.BOTTOM_LEFT");
086
087    /** Bottom-Right. */
088    public static final RectangleAnchor BOTTOM_RIGHT 
089        = new RectangleAnchor("RectangleAnchor.BOTTOM_RIGHT");
090
091    /** Left. */
092    public static final RectangleAnchor LEFT 
093        = new RectangleAnchor("RectangleAnchor.LEFT");
094
095    /** Right. */
096    public static final RectangleAnchor RIGHT 
097        = new RectangleAnchor("RectangleAnchor.RIGHT");
098
099    /** The name. */
100    private String name;
101
102    /**
103     * Private constructor.
104     *
105     * @param name  the name.
106     */
107    private RectangleAnchor(final String name) {
108        this.name = name;
109    }
110
111    /**
112     * Returns a string representing the object.
113     *
114     * @return The string.
115     */
116    public String toString() {
117        return this.name;
118    }
119
120    /**
121     * Returns <code>true</code> if this object is equal to the specified 
122     * object, and <code>false</code> otherwise.
123     *
124     * @param obj  the other object (<code>null</code> permitted).
125     *
126     * @return A boolean.
127     */
128    public boolean equals(final Object obj) {
129
130        if (this == obj) {
131            return true;
132        }
133        if (!(obj instanceof RectangleAnchor)) {
134            return false;
135        }
136
137        final RectangleAnchor order = (RectangleAnchor) obj;
138        if (!this.name.equals(order.name)) {
139            return false;
140        }
141
142        return true;
143    }
144
145    /**
146     * Returns a hash code value for the object.
147     *
148     * @return The hashcode
149     */
150    public int hashCode() {
151        return this.name.hashCode();
152    }
153
154    /**
155     * Returns the (x, y) coordinates of the specified anchor.
156     * 
157     * @param rectangle  the rectangle.
158     * @param anchor  the anchor.
159     * 
160     * @return The (x, y) coordinates.
161     */
162    public static Point2D coordinates(final Rectangle2D rectangle, 
163                                      final RectangleAnchor anchor) {
164        Point2D result = new Point2D.Double();
165        if (anchor == RectangleAnchor.CENTER) {
166            result.setLocation(rectangle.getCenterX(), rectangle.getCenterY());
167        }
168        else if (anchor == RectangleAnchor.TOP) {
169            result.setLocation(rectangle.getCenterX(), rectangle.getMinY());
170        }
171        else if (anchor == RectangleAnchor.BOTTOM) {
172            result.setLocation(rectangle.getCenterX(), rectangle.getMaxY());
173        }
174        else if (anchor == RectangleAnchor.LEFT) {
175            result.setLocation(rectangle.getMinX(), rectangle.getCenterY());
176        }
177        else if (anchor == RectangleAnchor.RIGHT) {
178            result.setLocation(rectangle.getMaxX(), rectangle.getCenterY());
179        }
180        else if (anchor == RectangleAnchor.TOP_LEFT) {
181            result.setLocation(rectangle.getMinX(), rectangle.getMinY());
182        }
183        else if (anchor == RectangleAnchor.TOP_RIGHT) {
184            result.setLocation(rectangle.getMaxX(), rectangle.getMinY());
185        }
186        else if (anchor == RectangleAnchor.BOTTOM_LEFT) {
187            result.setLocation(rectangle.getMinX(), rectangle.getMaxY());
188        }
189        else if (anchor == RectangleAnchor.BOTTOM_RIGHT) {
190            result.setLocation(rectangle.getMaxX(), rectangle.getMaxY());
191        }
192        return result;
193    }
194    
195    /**
196     * Creates a new rectangle with the specified dimensions that is aligned to
197     * the given anchor point <code>(anchorX, anchorY)</code>.
198     * 
199     * @param dimensions  the dimensions (<code>null</code> not permitted).
200     * @param anchorX  the x-anchor.
201     * @param anchorY  the y-anchor.
202     * @param anchor  the anchor (<code>null</code> not permitted).
203     * 
204     * @return A rectangle.
205     */
206    public static Rectangle2D createRectangle(final Size2D dimensions,
207                                              final double anchorX,
208                                              final double anchorY,
209                                              final RectangleAnchor anchor) {
210        Rectangle2D result = null;
211        final double w = dimensions.getWidth();
212        final double h = dimensions.getHeight();
213        if (anchor == RectangleAnchor.CENTER) {
214            result = new Rectangle2D.Double(
215                anchorX - w / 2.0, anchorY - h / 2.0, w, h
216            );
217        }
218        else if (anchor == RectangleAnchor.TOP) {
219            result = new Rectangle2D.Double(
220                anchorX - w / 2.0, anchorY - h / 2.0, w, h
221            );
222        }
223        else if (anchor == RectangleAnchor.BOTTOM) {
224            result = new Rectangle2D.Double(
225                anchorX - w / 2.0, anchorY - h / 2.0, w, h
226            );
227        }
228        else if (anchor == RectangleAnchor.LEFT) {
229            result = new Rectangle2D.Double(
230                anchorX, anchorY - h / 2.0, w, h
231            );
232        }
233        else if (anchor == RectangleAnchor.RIGHT) {
234            result = new Rectangle2D.Double(
235                anchorX - w, anchorY - h / 2.0, w, h
236            );
237        }
238        else if (anchor == RectangleAnchor.TOP_LEFT) {
239            result = new Rectangle2D.Double(
240                anchorX - w / 2.0, anchorY - h / 2.0, w, h
241            );
242        }
243        else if (anchor == RectangleAnchor.TOP_RIGHT) {
244            result = new Rectangle2D.Double(
245                anchorX - w / 2.0, anchorY - h / 2.0, w, h
246            );
247        }
248        else if (anchor == RectangleAnchor.BOTTOM_LEFT) {
249            result = new Rectangle2D.Double(
250                anchorX - w / 2.0, anchorY - h / 2.0, w, h
251            );
252        }
253        else if (anchor == RectangleAnchor.BOTTOM_RIGHT) {
254            result = new Rectangle2D.Double(
255                anchorX - w / 2.0, anchorY - h / 2.0, w, h
256            );
257        }
258        return result;
259    }
260    
261    /**
262     * Ensures that serialization returns the unique instances.
263     * 
264     * @return The object.
265     * 
266     * @throws ObjectStreamException if there is a problem.
267     */
268    private Object readResolve() throws ObjectStreamException {
269        RectangleAnchor result = null;
270        if (this.equals(RectangleAnchor.CENTER)) {
271            result = RectangleAnchor.CENTER;
272        }
273        else if (this.equals(RectangleAnchor.TOP)) {
274            result = RectangleAnchor.TOP;
275        }
276        else if (this.equals(RectangleAnchor.BOTTOM)) {
277            result = RectangleAnchor.BOTTOM;
278        }
279        else if (this.equals(RectangleAnchor.LEFT)) {
280            result = RectangleAnchor.LEFT;
281        }
282        else if (this.equals(RectangleAnchor.RIGHT)) {
283            result = RectangleAnchor.RIGHT;
284        }
285        else if (this.equals(RectangleAnchor.TOP_LEFT)) {
286            result = RectangleAnchor.TOP_LEFT;
287        }
288        else if (this.equals(RectangleAnchor.TOP_RIGHT)) {
289            result = RectangleAnchor.TOP_RIGHT;
290        }
291        else if (this.equals(RectangleAnchor.BOTTOM_LEFT)) {
292            result = RectangleAnchor.BOTTOM_LEFT;
293        }
294        else if (this.equals(RectangleAnchor.BOTTOM_RIGHT)) {
295            result = RectangleAnchor.BOTTOM_RIGHT;
296        }
297        return result;
298    }
299    
300}