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     * LabelBlock.java
029     * ---------------
030     * (C) Copyright 2004-2007, by Object Refinery Limited.
031     *
032     * Original Author:  David Gilbert (for Object Refinery Limited);
033     * Contributor(s):   Pierre-Marie Le Biot;
034     *
035     * $Id: LabelBlock.java,v 1.8.2.5 2007/03/16 11:28:16 mungady Exp $
036     *
037     * Changes:
038     * --------
039     * 22-Oct-2004 : Version 1 (DG);
040     * 19-Apr-2005 : Added optional tooltip and URL text items,
041     *               draw() method now returns entities if 
042     *               requested (DG);
043     * 13-May-2005 : Added methods to set the font (DG);
044     * 01-Sep-2005 : Added paint management (PMLB);
045     *               Implemented equals() and clone() (PublicCloneable) (DG);
046     * ------------- JFREECHART 1.0.x ---------------------------------------------
047     * 20-Jul-2006 : Fixed entity area in draw() method (DG);
048     * 16-Mar-2007 : Fixed serialization when using GradientPaint (DG);
049     * 
050     */
051    
052    package org.jfree.chart.block;
053    
054    import java.awt.Color;
055    import java.awt.Font;
056    import java.awt.Graphics2D;
057    import java.awt.Paint;
058    import java.awt.Shape;
059    import java.awt.geom.Rectangle2D;
060    import java.io.IOException;
061    import java.io.ObjectInputStream;
062    import java.io.ObjectOutputStream;
063    
064    import org.jfree.chart.entity.ChartEntity;
065    import org.jfree.chart.entity.StandardEntityCollection;
066    import org.jfree.io.SerialUtilities;
067    import org.jfree.text.TextBlock;
068    import org.jfree.text.TextBlockAnchor;
069    import org.jfree.text.TextUtilities;
070    import org.jfree.ui.Size2D;
071    import org.jfree.util.ObjectUtilities;
072    import org.jfree.util.PaintUtilities;
073    import org.jfree.util.PublicCloneable;
074    
075    /**
076     * A block containing a label.
077     */
078    public class LabelBlock extends AbstractBlock 
079                                    implements Block, PublicCloneable {
080        
081        /** 
082         * The text for the label - retained in case the label needs 
083         * regenerating (for example, to change the font). 
084         */
085        private String text;
086        
087        /** The label. */
088        private TextBlock label;
089        
090        /** The font. */
091        private Font font;
092        
093        /** The tool tip text (can be <code>null</code>). */
094        private String toolTipText;
095        
096        /** The URL text (can be <code>null</code>). */
097        private String urlText;
098        
099        /** The default color. */
100        public static final Paint DEFAULT_PAINT = Color.black;
101    
102        /** The paint. */
103        private transient Paint paint;
104        
105        /**
106         * Creates a new label block.
107         * 
108         * @param label  the label (<code>null</code> not permitted).
109         */
110        public LabelBlock(String label) {
111            this(label, new Font("SansSerif", Font.PLAIN, 10), DEFAULT_PAINT);
112        }
113        
114        /**
115         * Creates a new label block.
116         * 
117         * @param text  the text for the label (<code>null</code> not permitted).
118         * @param font  the font (<code>null</code> not permitted).
119         */
120        public LabelBlock(String text, Font font) {        
121            this(text, font, DEFAULT_PAINT);
122        }
123        
124        /**
125         * Creates a new label block.
126         *
127         * @param text  the text for the label (<code>null</code> not permitted).
128         * @param font  the font (<code>null</code> not permitted).
129         * @param paint the paint (<code>null</code> not permitted).
130         */
131        public LabelBlock(String text, Font font, Paint paint) {        
132            this.text = text;
133            this.paint = paint; 
134            this.label = TextUtilities.createTextBlock(text, font, this.paint); 
135            this.font = font;
136            this.toolTipText = null;
137            this.urlText = null;
138        }
139        
140        /**
141         * Returns the font.
142         *
143         * @return The font (never <code>null</code>).
144         * 
145         * @see #setFont(Font)
146         */
147        public Font getFont() {
148            return this.font;    
149        }
150        
151        /**
152         * Sets the font and regenerates the label.
153         *
154         * @param font  the font (<code>null</code> not permitted).
155         * 
156         * @see #getFont()
157         */
158        public void setFont(Font font) {
159            if (font == null) {
160                throw new IllegalArgumentException("Null 'font' argument.");
161            }
162            this.font = font;
163            this.label = TextUtilities.createTextBlock(this.text, font, this.paint);
164        }
165       
166        /**
167         * Returns the paint.
168         *
169         * @return The paint (never <code>null</code>).
170         * 
171         * @see #setPaint(Paint)
172         */
173        public Paint getPaint() {
174            return this.paint;   
175        }
176       
177        /**
178         * Sets the paint and regenerates the label.
179         *
180         * @param paint  the paint (<code>null</code> not permitted).
181         * 
182         * @see #getPaint()
183         */
184        public void setPaint(Paint paint) {
185            if (paint == null) {
186                throw new IllegalArgumentException("Null 'paint' argument.");
187            }
188            this.paint = paint;
189            this.label = TextUtilities.createTextBlock(this.text, this.font, 
190                    this.paint);
191        }
192    
193        /**
194         * Returns the tool tip text.
195         * 
196         * @return The tool tip text (possibly <code>null</code>).
197         * 
198         * @see #setToolTipText(String)
199         */
200        public String getToolTipText() {
201            return this.toolTipText;
202        }
203        
204        /**
205         * Sets the tool tip text.
206         * 
207         * @param text  the text (<code>null</code> permitted).
208         * 
209         * @see #getToolTipText()
210         */
211        public void setToolTipText(String text) {
212            this.toolTipText = text;   
213        }
214        
215        /**
216         * Returns the URL text.
217         * 
218         * @return The URL text (possibly <code>null</code>).
219         * 
220         * @see #setURLText(String)
221         */
222        public String getURLText() {
223            return this.urlText;
224        }
225        
226        /**
227         * Sets the URL text.
228         * 
229         * @param text  the text (<code>null</code> permitted).
230         * 
231         * @see #getURLText()
232         */
233        public void setURLText(String text) {
234            this.urlText = text;   
235        }
236        
237        /**
238         * Arranges the contents of the block, within the given constraints, and 
239         * returns the block size.
240         * 
241         * @param g2  the graphics device.
242         * @param constraint  the constraint (<code>null</code> not permitted).
243         * 
244         * @return The block size (in Java2D units, never <code>null</code>).
245         */
246        public Size2D arrange(Graphics2D g2, RectangleConstraint constraint) {
247            g2.setFont(this.font);
248            Size2D s = this.label.calculateDimensions(g2);
249            return new Size2D(calculateTotalWidth(s.getWidth()), 
250                    calculateTotalHeight(s.getHeight()));
251        }
252        
253        /**
254         * Draws the block.
255         * 
256         * @param g2  the graphics device.
257         * @param area  the area.
258         */
259        public void draw(Graphics2D g2, Rectangle2D area) {
260            draw(g2, area, null);
261        }
262        
263        /**
264         * Draws the block within the specified area.
265         * 
266         * @param g2  the graphics device.
267         * @param area  the area.
268         * @param params  ignored (<code>null</code> permitted).
269         * 
270         * @return Always <code>null</code>.
271         */
272        public Object draw(Graphics2D g2, Rectangle2D area, Object params) {
273            area = trimMargin(area);
274            drawBorder(g2, area);
275            area = trimBorder(area);
276            area = trimPadding(area);
277            
278            // check if we need to collect chart entities from the container
279            EntityBlockParams ebp = null;
280            StandardEntityCollection sec = null;
281            Shape entityArea = null;
282            if (params instanceof EntityBlockParams) {
283                ebp = (EntityBlockParams) params;
284                if (ebp.getGenerateEntities()) {
285                    sec = new StandardEntityCollection();
286                    entityArea = (Shape) area.clone();
287                }
288            }
289            g2.setPaint(this.paint);
290            g2.setFont(this.font);
291            this.label.draw(g2, (float) area.getX(), (float) area.getY(), 
292                    TextBlockAnchor.TOP_LEFT);
293            BlockResult result = null;
294            if (ebp != null && sec != null) {
295                if (this.toolTipText != null || this.urlText != null) {
296                    ChartEntity entity = new ChartEntity(entityArea, 
297                            this.toolTipText, this.urlText);   
298                    sec.add(entity);
299                    result = new BlockResult();
300                    result.setEntityCollection(sec);
301                }
302            }
303            return result;
304        }
305        
306        /**
307         * Tests this <code>LabelBlock</code> for equality with an arbitrary 
308         * object.
309         * 
310         * @param obj  the object (<code>null</code> permitted).
311         * 
312         * @return A boolean.
313         */
314        public boolean equals(Object obj) {
315            if (!(obj instanceof LabelBlock)) {
316                return false;
317            }
318            LabelBlock that = (LabelBlock) obj;
319            if (!this.text.equals(that.text)) {
320                return false;
321            }
322            if (!this.font.equals(that.font)) {
323                return false;
324            }
325            if (!PaintUtilities.equal(this.paint, that.paint)) {
326                return false;
327            }
328            if (!ObjectUtilities.equal(this.toolTipText, that.toolTipText)) {
329                return false;
330            }
331            if (!ObjectUtilities.equal(this.urlText, that.urlText)) {
332                return false;
333            }
334            return super.equals(obj);
335        }
336    
337        /**
338         * Returns a clone of this <code>LabelBlock</code> instance.
339         * 
340         * @return A clone.
341         * 
342         * @throws CloneNotSupportedException if there is a problem cloning.
343         */
344        public Object clone() throws CloneNotSupportedException {
345            return super.clone();
346        }
347        
348        /**
349         * Provides serialization support.
350         *
351         * @param stream  the output stream.
352         *
353         * @throws IOException if there is an I/O error.
354         */
355        private void writeObject(ObjectOutputStream stream) throws IOException {
356            stream.defaultWriteObject();
357            SerialUtilities.writePaint(this.paint, stream);
358        }
359    
360        /**
361         * Provides serialization support.
362         *
363         * @param stream  the input stream.
364         *
365         * @throws IOException  if there is an I/O error.
366         * @throws ClassNotFoundException  if there is a classpath problem.
367         */
368        private void readObject(ObjectInputStream stream) 
369            throws IOException, ClassNotFoundException {
370            stream.defaultReadObject();
371            this.paint = SerialUtilities.readPaint(stream);
372        }
373    
374    }