001/* ========================================================================
002 * JCommon : a free general purpose class 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/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 * TextFragment.java
029 * -----------------
030 * (C) Copyright 2003-2007, by Object Refinery Limited and Contributors.
031 *
032 * Original Author:  David Gilbert (for Object Refinery Limited);
033 * Contributor(s):   -;
034 *
035 * $Id: TextFragment.java,v 1.13 2007/03/16 10:25:58 mungady Exp $
036 *
037 * Changes
038 * -------
039 * 07-Nov-2003 : Version 1 (DG);
040 * 25-Nov-2003 : Fixed bug in the dimension calculation (DG);
041 * 22-Dec-2003 : Added workaround for Java bug 4245442 (DG);
042 * 29-Jan-2004 : Added paint attribute (DG);
043 * 22-Mar-2004 : Added equals() method and implemented Serializable (DG);
044 * 01-Apr-2004 : Changed java.awt.geom.Dimension2D to org.jfree.ui.Size2D 
045 *               because of JDK bug 4976448 which persists on JDK 1.3.1 (DG);
046 * 30-Sep-2004 : Moved drawRotatedString() from RefineryUtilities 
047 *               --> TextUtilities (DG);
048 * 16-Mar-2007 : Fixed serialization for GradientPaint (DG);
049 *
050 */
051 
052package org.jfree.text;
053
054import java.awt.Color;
055import java.awt.Font;
056import java.awt.FontMetrics;
057import java.awt.Graphics2D;
058import java.awt.Paint;
059import java.awt.font.LineMetrics;
060import java.awt.geom.Rectangle2D;
061import java.io.IOException;
062import java.io.ObjectInputStream;
063import java.io.ObjectOutputStream;
064import java.io.Serializable;
065
066import org.jfree.io.SerialUtilities;
067import org.jfree.ui.Size2D;
068import org.jfree.ui.TextAnchor;
069import org.jfree.util.Log;
070import org.jfree.util.LogContext;
071
072/**
073 * A text item, with an associated font, that fits on a single line (see 
074 * {@link TextLine}).  Instances of the class are immutable.
075 */
076public class TextFragment implements Serializable {
077
078    /** For serialization. */
079    private static final long serialVersionUID = 4465945952903143262L;
080    
081    /** The default font. */
082    public static final Font DEFAULT_FONT = new Font("Serif", Font.PLAIN, 12);
083    
084    /** The default text color. */
085    public static final Paint DEFAULT_PAINT = Color.black;
086    
087    /** The text. */
088    private String text;
089    
090    /** The font. */
091    private Font font;
092    
093    /** The text color. */
094    private transient Paint paint;
095    
096    /** 
097     * The baseline offset (can be used to simulate subscripts and 
098     * superscripts). 
099     */
100    private float baselineOffset;
101    
102    /** Access to logging facilities. */
103    protected static final LogContext logger = Log.createContext(
104            TextFragment.class);
105    
106    /**
107     * Creates a new text fragment.
108     * 
109     * @param text  the text (<code>null</code> not permitted).
110     */
111    public TextFragment(final String text) {
112        this(text, DEFAULT_FONT, DEFAULT_PAINT);
113    }
114    
115    /**
116     * Creates a new text fragment.
117     * 
118     * @param text  the text (<code>null</code> not permitted).
119     * @param font  the font (<code>null</code> not permitted).
120     */
121    public TextFragment(final String text, final Font font) {
122        this(text, font, DEFAULT_PAINT);
123    }
124
125    /**
126     * Creates a new text fragment.
127     * 
128     * @param text  the text (<code>null</code> not permitted).
129     * @param font  the font (<code>null</code> not permitted).
130     * @param paint  the text color (<code>null</code> not permitted).
131     */
132    public TextFragment(final String text, final Font font, final Paint paint) {
133        this(text, font, paint, 0.0f);
134    }
135
136    /**
137     * Creates a new text fragment.
138     * 
139     * @param text  the text (<code>null</code> not permitted).
140     * @param font  the font (<code>null</code> not permitted).
141     * @param paint  the text color (<code>null</code> not permitted).
142     * @param baselineOffset  the baseline offset.
143     */
144    public TextFragment(final String text, final Font font, final Paint paint,
145                        final float baselineOffset) {
146        if (text == null) {
147            throw new IllegalArgumentException("Null 'text' argument.");  
148        }
149        if (font == null) {
150            throw new IllegalArgumentException("Null 'font' argument.");
151        }
152        if (paint == null) {
153            throw new IllegalArgumentException("Null 'paint' argument.");
154        }
155        this.text = text;
156        this.font = font;
157        this.paint = paint;
158        this.baselineOffset = baselineOffset;
159    }
160
161    /**
162     * Returns the text.
163     * 
164     * @return The text (possibly <code>null</code>).
165     */
166    public String getText() {
167        return this.text;
168    }
169    
170    /**
171     * Returns the font.
172     * 
173     * @return The font (never <code>null</code>).
174     */
175    public Font getFont() {
176        return this.font;
177    }
178    
179    /**
180     * Returns the text paint.
181     * 
182     * @return The text paint (never <code>null</code>).
183     */
184    public Paint getPaint() {
185        return this.paint;
186    }
187    
188    /**
189     * Returns the baseline offset.
190     * 
191     * @return The baseline offset.
192     */
193    public float getBaselineOffset() {
194        return this.baselineOffset;   
195    }
196    
197    /**
198     * Draws the text fragment.
199     * 
200     * @param g2  the graphics device.
201     * @param anchorX  the x-coordinate of the anchor point.
202     * @param anchorY  the y-coordinate of the anchor point.
203     * @param anchor  the location of the text that is aligned to the anchor 
204     *                point.
205     * @param rotateX  the x-coordinate of the rotation point.
206     * @param rotateY  the y-coordinate of the rotation point.
207     * @param angle  the angle.
208     */
209    public void draw(final Graphics2D g2, final float anchorX, 
210                     final float anchorY, final TextAnchor anchor,
211                     final float rotateX, final float rotateY, 
212                     final double angle) {
213    
214        g2.setFont(this.font);
215        g2.setPaint(this.paint);
216        TextUtilities.drawRotatedString(this.text, g2, anchorX, anchorY 
217                + this.baselineOffset, anchor, angle, rotateX, rotateY);
218    
219    }
220    
221    /**
222     * Calculates the dimensions of the text fragment.
223     * 
224     * @param g2  the graphics device.
225     * 
226     * @return The width and height of the text.
227     */
228    public Size2D calculateDimensions(final Graphics2D g2) {
229        final FontMetrics fm = g2.getFontMetrics(this.font);
230        final Rectangle2D bounds = TextUtilities.getTextBounds(this.text, g2, 
231                fm);
232        final Size2D result = new Size2D(bounds.getWidth(), bounds.getHeight());
233        return result;
234    }
235    
236    /**
237     * Calculates the vertical offset between the baseline and the specified 
238     * text anchor.
239     * 
240     * @param g2  the graphics device.
241     * @param anchor  the anchor.
242     * 
243     * @return the offset.
244     */
245    public float calculateBaselineOffset(final Graphics2D g2, 
246                                         final TextAnchor anchor) {
247        float result = 0.0f;
248        final FontMetrics fm = g2.getFontMetrics(this.font);
249        final LineMetrics lm = fm.getLineMetrics("ABCxyz", g2);
250        if (anchor == TextAnchor.TOP_LEFT || anchor == TextAnchor.TOP_CENTER
251                                          || anchor == TextAnchor.TOP_RIGHT) {
252            result = lm.getAscent();
253        }
254        else if (anchor == TextAnchor.BOTTOM_LEFT 
255                || anchor == TextAnchor.BOTTOM_CENTER
256                || anchor == TextAnchor.BOTTOM_RIGHT) {
257            result = -lm.getDescent() - lm.getLeading();
258        }
259        return result;                                             
260    }
261    
262    /**
263     * Tests this instance for equality with an arbitrary object.
264     * 
265     * @param obj  the object to test against (<code>null</code> permitted).
266     * 
267     * @return A boolean.
268     */
269    public boolean equals(final Object obj) {
270        if (obj == null) {
271            return false;   
272        }
273        if (obj == this) {
274            return true;   
275        }
276        if (obj instanceof TextFragment) {
277            final TextFragment tf = (TextFragment) obj;
278            if (!this.text.equals(tf.text)) {
279                return false;   
280            }
281            if (!this.font.equals(tf.font)) {
282                return false;   
283            }
284            if (!this.paint.equals(tf.paint)) {
285                return false;   
286            }
287            return true;
288        }
289        return false;
290    }
291
292    /**
293     * Returns a hash code for this object.
294     * 
295     * @return A hash code.
296     */
297    public int hashCode() {
298        int result;
299        result = (this.text != null ? this.text.hashCode() : 0);
300        result = 29 * result + (this.font != null ? this.font.hashCode() : 0);
301        result = 29 * result + (this.paint != null ? this.paint.hashCode() : 0);
302        return result;
303    }
304
305    /**
306     * Provides serialization support.
307     *
308     * @param stream  the output stream.
309     *
310     * @throws IOException  if there is an I/O error.
311     */
312    private void writeObject(final ObjectOutputStream stream) 
313        throws IOException {
314        stream.defaultWriteObject();
315        SerialUtilities.writePaint(this.paint, stream);
316    }
317
318    /**
319     * Provides serialization support.
320     *
321     * @param stream  the input stream.
322     *
323     * @throws IOException  if there is an I/O error.
324     * @throws ClassNotFoundException  if there is a classpath problem.
325     */
326    private void readObject(final ObjectInputStream stream) 
327        throws IOException, ClassNotFoundException {
328        stream.defaultReadObject();
329        this.paint = SerialUtilities.readPaint(stream);
330    }
331   
332}