Source for org.jfree.text.TextBlock

   1: /* ========================================================================
   2:  * JCommon : a free general purpose class library for the Java(tm) platform
   3:  * ========================================================================
   4:  *
   5:  * (C) Copyright 2000-2005, by Object Refinery Limited and Contributors.
   6:  * 
   7:  * Project Info:  http://www.jfree.org/jcommon/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:  * TextBlock.java
  29:  * --------------
  30:  * (C) Copyright 2003, 2004, by Object Refinery Limited and Contributors.
  31:  *
  32:  * Original Author:  David Gilbert (for Object Refinery Limited);
  33:  * Contributor(s):   -;
  34:  *
  35:  * $Id: TextBlock.java,v 1.13 2005/10/18 13:17:16 mungady Exp $
  36:  *
  37:  * Changes
  38:  * -------
  39:  * 07-Nov-2003 : Version 1 (DG);
  40:  * 22-Dec-2003 : Added workaround for Java bug 4245442 (DG);
  41:  * 09-Jan-2004 : Added an extra draw() method for no rotation case (DG);
  42:  * 25-Feb-2004 : Added getLines() method (DG);
  43:  * 22-Mar-2004 : Added equals() method and implemented Serializable (DG);
  44:  * 24-Mar-2004 : Added 'paint' argument to addLine() method (DG);
  45:  * 01-Apr-2004 : Changed java.awt.geom.Dimension2D to org.jfree.ui.Size2D 
  46:  *               because of JDK bug 4976448 which persists on JDK 1.3.1 (DG);
  47:  * 04-Oct-2004 : Renamed ShapeUtils --> ShapeUtilities (DG);
  48:  *
  49:  */
  50:  
  51: package org.jfree.text;
  52: 
  53: import java.awt.Font;
  54: import java.awt.Graphics2D;
  55: import java.awt.Paint;
  56: import java.awt.Shape;
  57: import java.awt.geom.Rectangle2D;
  58: import java.io.Serializable;
  59: import java.util.Collections;
  60: import java.util.Iterator;
  61: import java.util.List;
  62: 
  63: import org.jfree.ui.HorizontalAlignment;
  64: import org.jfree.ui.Size2D;
  65: import org.jfree.ui.TextAnchor;
  66: import org.jfree.util.Log;
  67: import org.jfree.util.LogContext;
  68: import org.jfree.util.ShapeUtilities;
  69: 
  70: /**
  71:  * A list of {@link TextLine} objects that form a block of text.
  72:  * 
  73:  * @see TextUtilities#createTextBlock(String, Font, Paint)
  74:  *
  75:  * @author David Gilbert
  76:  */
  77: public class TextBlock implements Serializable {
  78: 
  79:     /** For serialization. */
  80:     private static final long serialVersionUID = -4333175719424385526L;
  81:     
  82:     /** Storage for the lines of text. */
  83:     private List lines;
  84:     
  85:     /** The alignment of the lines. */
  86:     private HorizontalAlignment lineAlignment;
  87:     
  88:     /** Access to logging facilities. */
  89:     protected static final LogContext logger 
  90:         = Log.createContext(TextBlock.class);
  91: 
  92:     /**
  93:      * Creates a new empty text block.
  94:      */
  95:     public TextBlock() {
  96:         this.lines = new java.util.ArrayList();
  97:         this.lineAlignment = HorizontalAlignment.CENTER;
  98:     }
  99:     
 100:     /**
 101:      * Returns the alignment of the lines of text within the block.
 102:      * 
 103:      * @return The alignment (never <code>null</code>).
 104:      */
 105:     public HorizontalAlignment getLineAlignment() {
 106:         return this.lineAlignment;   
 107:     }
 108:     
 109:     /**
 110:      * Sets the alignment of the lines of text within the block.
 111:      * 
 112:      * @param alignment  the alignment (<code>null</code> not permitted).
 113:      */
 114:     public void setLineAlignment(HorizontalAlignment alignment) {
 115:         if (alignment == null) {
 116:             throw new IllegalArgumentException("Null 'alignment' argument.");
 117:         }
 118:         this.lineAlignment = alignment;   
 119:     }
 120:     
 121:     /**
 122:      * Adds a line of text that will be displayed using the specified font.
 123:      * 
 124:      * @param text  the text.
 125:      * @param font  the font.
 126:      * @param paint  the paint.
 127:      */
 128:     public void addLine(final String text, final Font font, final Paint paint) {
 129:         addLine(new TextLine(text, font, paint));
 130:     }
 131:     
 132:     /**
 133:      * Adds a {@link TextLine} to the block.
 134:      * 
 135:      * @param line  the line.
 136:      */
 137:     public void addLine(final TextLine line) {
 138:         this.lines.add(line);    
 139:     }
 140:     
 141:     /**
 142:      * Returns the last line in the block.
 143:      * 
 144:      * @return The last line in the block.
 145:      */
 146:     public TextLine getLastLine() {
 147:         TextLine last = null;
 148:         final int index = this.lines.size() - 1;
 149:         if (index >= 0) {
 150:             last = (TextLine) this.lines.get(index);
 151:         }
 152:         return last;
 153:     }
 154:     
 155:     /**
 156:      * Returns an unmodifiable list containing the lines for the text block.
 157:      *
 158:      * @return A list of {@link TextLine} objects.
 159:      */
 160:     public List getLines() {
 161:         return Collections.unmodifiableList(this.lines);
 162:     }
 163:     
 164:     /**
 165:      * Returns the width and height of the text block.
 166:      * 
 167:      * @param g2  the graphics device.
 168:      * 
 169:      * @return The width and height.
 170:      */
 171:     public Size2D calculateDimensions(final Graphics2D g2) {
 172:         double width = 0.0;
 173:         double height = 0.0;
 174:         final Iterator iterator = this.lines.iterator();
 175:         while (iterator.hasNext()) {
 176:             final TextLine line = (TextLine) iterator.next();
 177:             final Size2D dimension = line.calculateDimensions(g2);
 178:             width = Math.max(width, dimension.getWidth());
 179:             height = height + dimension.getHeight();
 180:         }
 181:         if (logger.isDebugEnabled()) {
 182:             logger.debug("width = " + width + ", height = " + height);   
 183:         }
 184:         return new Size2D(width, height);
 185:     }
 186:     
 187:     /**
 188:      * Returns the bounds of the text block.
 189:      * 
 190:      * @param g2  the graphics device (<code>null</code> not permitted).
 191:      * @param anchorX  the x-coordinate for the anchor point.
 192:      * @param anchorY  the y-coordinate for the anchor point.
 193:      * @param anchor  the text block anchor (<code>null</code> not permitted).
 194:      * @param rotateX  the x-coordinate for the rotation point.
 195:      * @param rotateY  the y-coordinate for the rotation point.
 196:      * @param angle  the rotation angle.
 197:      * 
 198:      * @return The bounds.
 199:      */
 200:     public Shape calculateBounds(final Graphics2D g2,
 201:                                  final float anchorX, final float anchorY, 
 202:                                  final TextBlockAnchor anchor,
 203:                                  final float rotateX, final float rotateY, 
 204:                                  final double angle) {
 205:         
 206:         final Size2D d = calculateDimensions(g2);
 207:         final float[] offsets = calculateOffsets(
 208:             anchor, d.getWidth(), d.getHeight()
 209:         );
 210:         final Rectangle2D bounds = new Rectangle2D.Double(
 211:             anchorX + offsets[0], anchorY + offsets[1], 
 212:             d.getWidth(), d.getHeight()
 213:         );
 214:         final Shape rotatedBounds = ShapeUtilities.rotateShape(
 215:             bounds, angle, rotateX, rotateY
 216:         );
 217:         return rotatedBounds;   
 218:         
 219:     }
 220:     
 221:     /**
 222:      * Draws the text block at a specific location.
 223:      * 
 224:      * @param g2  the graphics device.
 225:      * @param x  the x-coordinate for the anchor point.
 226:      * @param y  the y-coordinate for the anchor point.
 227:      * @param anchor  the anchor point.
 228:      */
 229:     public void draw(final Graphics2D g2, final float x, final float y, 
 230:                      final TextBlockAnchor anchor) {
 231:         draw(g2, x, y, anchor, 0.0f, 0.0f, 0.0);
 232:     }
 233:     
 234:     /**
 235:      * Draws the text block, aligning it with the specified anchor point and 
 236:      * rotating it about the specified rotation point.
 237:      * 
 238:      * @param g2  the graphics device.
 239:      * @param anchorX  the x-coordinate for the anchor point.
 240:      * @param anchorY  the y-coordinate for the anchor point.
 241:      * @param anchor  the point on the text block that is aligned to the 
 242:      *                anchor point.
 243:      * @param rotateX  the x-coordinate for the rotation point.
 244:      * @param rotateY  the x-coordinate for the rotation point.
 245:      * @param angle  the rotation (in radians).
 246:      */
 247:     public void draw(final Graphics2D g2,
 248:                      final float anchorX, final float anchorY, 
 249:                      final TextBlockAnchor anchor,
 250:                      final float rotateX, final float rotateY, 
 251:                      final double angle) {
 252:     
 253:         final Size2D d = calculateDimensions(g2);
 254:         final float[] offsets = calculateOffsets(anchor, d.getWidth(), 
 255:                 d.getHeight());
 256:         final Iterator iterator = this.lines.iterator();
 257:         float yCursor = 0.0f;
 258:         while (iterator.hasNext()) {
 259:             TextLine line = (TextLine) iterator.next();
 260:             Size2D dimension = line.calculateDimensions(g2);
 261:             float lineOffset = 0.0f;
 262:             if (this.lineAlignment == HorizontalAlignment.CENTER) {
 263:                 lineOffset = (float) (d.getWidth() - dimension.getWidth()) 
 264:                     / 2.0f;   
 265:             }
 266:             else if (this.lineAlignment == HorizontalAlignment.RIGHT) {
 267:                 lineOffset = (float) (d.getWidth() - dimension.getWidth());   
 268:             }
 269:             line.draw(
 270:                 g2, anchorX + offsets[0] + lineOffset, anchorY + offsets[1] + yCursor,
 271:                 TextAnchor.TOP_LEFT, rotateX, rotateY, angle
 272:             );
 273:             yCursor = yCursor + (float) dimension.getHeight();
 274:         }
 275:         
 276:     }
 277:  
 278:     /**
 279:      * Calculates the x and y offsets required to align the text block with the
 280:      * specified anchor point.  This assumes that the top left of the text 
 281:      * block is at (0.0, 0.0).
 282:      * 
 283:      * @param anchor  the anchor position.
 284:      * @param width  the width of the text block.
 285:      * @param height  the height of the text block.
 286:      * 
 287:      * @return The offsets (float[0] = x offset, float[1] = y offset).
 288:      */
 289:     private float[] calculateOffsets(final TextBlockAnchor anchor, 
 290:                                      final double width, final double height) {
 291:         final float[] result = new float[2];
 292:         float xAdj = 0.0f;
 293:         float yAdj = 0.0f;
 294: 
 295:         if (anchor == TextBlockAnchor.TOP_CENTER
 296:                 || anchor == TextBlockAnchor.CENTER
 297:                 || anchor == TextBlockAnchor.BOTTOM_CENTER) {
 298:                     
 299:             xAdj = (float) -width / 2.0f;
 300:             
 301:         }
 302:         else if (anchor == TextBlockAnchor.TOP_RIGHT
 303:                 || anchor == TextBlockAnchor.CENTER_RIGHT
 304:                 || anchor == TextBlockAnchor.BOTTOM_RIGHT) {
 305:                     
 306:             xAdj = (float) -width;
 307:             
 308:         }
 309: 
 310:         if (anchor == TextBlockAnchor.TOP_LEFT
 311:                 || anchor == TextBlockAnchor.TOP_CENTER
 312:                 || anchor == TextBlockAnchor.TOP_RIGHT) {
 313:                     
 314:             yAdj = 0.0f;
 315:             
 316:         }
 317:         else if (anchor == TextBlockAnchor.CENTER_LEFT
 318:                 || anchor == TextBlockAnchor.CENTER
 319:                 || anchor == TextBlockAnchor.CENTER_RIGHT) {
 320:                     
 321:             yAdj = (float) -height / 2.0f;
 322:             
 323:         }
 324:         else if (anchor == TextBlockAnchor.BOTTOM_LEFT
 325:                 || anchor == TextBlockAnchor.BOTTOM_CENTER
 326:                 || anchor == TextBlockAnchor.BOTTOM_RIGHT) {
 327:                     
 328:             yAdj = (float) -height;
 329:             
 330:         }
 331:         result[0] = xAdj;
 332:         result[1] = yAdj;
 333:         return result;
 334:     }   
 335:     
 336:     /**
 337:      * Tests this object for equality with an arbitrary object.
 338:      * 
 339:      * @param obj  the object to test against (<code>null</code> permitted).
 340:      * 
 341:      * @return A boolean.
 342:      */
 343:     public boolean equals(final Object obj) {
 344:         if (obj == this) {
 345:             return true;   
 346:         }
 347:         if (obj instanceof TextBlock) {
 348:             final TextBlock block = (TextBlock) obj;
 349:             return this.lines.equals(block.lines);
 350:         }
 351:         return false;
 352:     }
 353: 
 354:     /**
 355:      * Returns a hash code for this object.
 356:      * 
 357:      * @return A hash code.
 358:      */
 359:     public int hashCode() {
 360:         return (this.lines != null ? this.lines.hashCode() : 0);
 361:     }
 362: }