001/* InlineView.java -- Renders HTML content 002 Copyright (C) 2006 Free Software Foundation, Inc. 003 004This file is part of GNU Classpath. 005 006GNU Classpath is free software; you can redistribute it and/or modify 007it under the terms of the GNU General Public License as published by 008the Free Software Foundation; either version 2, or (at your option) 009any later version. 010 011GNU Classpath is distributed in the hope that it will be useful, but 012WITHOUT ANY WARRANTY; without even the implied warranty of 013MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 014General Public License for more details. 015 016You should have received a copy of the GNU General Public License 017along with GNU Classpath; see the file COPYING. If not, write to the 018Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 01902110-1301 USA. 020 021Linking this library statically or dynamically with other modules is 022making a combined work based on this library. Thus, the terms and 023conditions of the GNU General Public License cover the whole 024combination. 025 026As a special exception, the copyright holders of this library give you 027permission to link this library with independent modules to produce an 028executable, regardless of the license terms of these independent 029modules, and to copy and distribute the resulting executable under 030terms of your choice, provided that you also meet, for each linked 031independent module, the terms and conditions of the license of that 032module. An independent module is a module which is not derived from 033or based on this library. If you modify this library, you may extend 034this exception to your version of the library, but you are not 035obligated to do so. If you do not wish to do so, delete this 036exception statement from your version. */ 037 038 039package javax.swing.text.html; 040 041import java.awt.FontMetrics; 042import java.awt.Shape; 043import java.text.BreakIterator; 044 045import javax.swing.event.DocumentEvent; 046import javax.swing.text.AttributeSet; 047import javax.swing.text.BadLocationException; 048import javax.swing.text.Document; 049import javax.swing.text.Element; 050import javax.swing.text.LabelView; 051import javax.swing.text.Segment; 052import javax.swing.text.View; 053import javax.swing.text.ViewFactory; 054 055/** 056 * Renders HTML content (identified by {@link HTML.Tag#CONTENT}). This is 057 * basically a {@link LabelView} that is adjusted to understand styles defined 058 * by stylesheets. 059 * 060 * @author Roman Kennke (kennke@aicas.com) 061 */ 062public class InlineView 063 extends LabelView 064{ 065 066 /** 067 * The attributes used by this view. 068 */ 069 private AttributeSet attributes; 070 071 /** 072 * The span of the longest word in this view. 073 * 074 * @see #getLongestWord() 075 */ 076 private float longestWord; 077 078 /** 079 * Indicates if we may wrap or not. 080 */ 081 private boolean nowrap; 082 083 /** 084 * Creates a new <code>InlineView</code> that renders the specified element. 085 * 086 * @param element the element for this view 087 */ 088 public InlineView(Element element) 089 { 090 super(element); 091 } 092 093 /** 094 * Receives notification that something was inserted into the document in 095 * a location that this view is responsible for. 096 * 097 * @param e the document event 098 * @param a the current allocation of this view 099 * @param f the view factory for creating new views 100 * 101 * @since 1.5 102 */ 103 public void insertUpdate(DocumentEvent e, Shape a, ViewFactory f) 104 { 105 // FIXME: What to do here? 106 super.insertUpdate(e, a, f); 107 } 108 109 /** 110 * Receives notification that something was removed from the document in 111 * a location that this view is responsible for. 112 * 113 * @param e the document event 114 * @param a the current allocation of this view 115 * @param f the view factory for creating new views 116 * 117 * @since 1.5 118 */ 119 public void removeUpdate(DocumentEvent e, Shape a, ViewFactory f) 120 { 121 // FIXME: What to do here? 122 super.removeUpdate(e, a, f); 123 } 124 125 /** 126 * Receives notification that attributes have changed in the document in 127 * a location that this view is responsible for. This calls 128 * {@link #setPropertiesFromAttributes}. 129 * 130 * @param e the document event 131 * @param a the current allocation of this view 132 * @param f the view factory for creating new views 133 * 134 * @since 1.5 135 */ 136 public void changedUpdate(DocumentEvent e, Shape a, ViewFactory f) 137 { 138 super.changedUpdate(e, a, f); 139 StyleSheet ss = getStyleSheet(); 140 attributes = ss.getViewAttributes(this); 141 preferenceChanged(null, true, true); 142 setPropertiesFromAttributes(); 143 } 144 145 /** 146 * Returns the attributes that are used for rendering. This is implemented 147 * to multiplex the attributes specified in the model with a stylesheet. 148 * 149 * @return the attributes that are used for rendering 150 */ 151 public AttributeSet getAttributes() 152 { 153 if (attributes == null) 154 { 155 StyleSheet ss = getStyleSheet(); 156 attributes = ss.getViewAttributes(this); 157 } 158 return attributes; 159 } 160 161 162 public int getBreakWeight(int axis, float pos, float len) 163 { 164 int weight; 165 if (nowrap) 166 weight = BadBreakWeight; 167 else 168 weight = super.getBreakWeight(axis, pos, len); 169 return weight; 170 } 171 172 public View breakView(int axis, int offset, float pos, float len) 173 { 174 // FIXME: Implement this. 175 return super.breakView(axis, offset, pos, len); 176 } 177 178 /** 179 * Loads the character style properties from the stylesheet. 180 */ 181 protected void setPropertiesFromAttributes() 182 { 183 super.setPropertiesFromAttributes(); 184 AttributeSet atts = getAttributes(); 185 Object o = atts.getAttribute(CSS.Attribute.TEXT_DECORATION); 186 187 // Check for underline. 188 boolean b = false; 189 if (o != null && o.toString().contains("underline")) 190 b = true; 191 setUnderline(b); 192 193 // Check for line-through. 194 b = false; 195 if (o != null && o.toString().contains("line-through")) 196 b = true; 197 setStrikeThrough(b); 198 199 // Check for vertical alignment (subscript/superscript). 200 o = atts.getAttribute(CSS.Attribute.VERTICAL_ALIGN); 201 202 // Subscript. 203 b = false; 204 if (o != null && o.toString().contains("sub")) 205 b = true; 206 setSubscript(b); 207 208 // Superscript. 209 b = false; 210 if (o != null && o.toString().contains("sup")) 211 b = true; 212 setSuperscript(b); 213 214 // Fetch nowrap setting. 215 o = atts.getAttribute(CSS.Attribute.WHITE_SPACE); 216 if (o != null && o.equals("nowrap")) 217 nowrap = true; 218 else 219 nowrap = false; 220 } 221 222 /** 223 * Returns the stylesheet used by this view. This returns the stylesheet 224 * of the <code>HTMLDocument</code> that is rendered by this view. 225 * 226 * @return the stylesheet used by this view 227 */ 228 protected StyleSheet getStyleSheet() 229 { 230 Document doc = getDocument(); 231 StyleSheet styleSheet = null; 232 if (doc instanceof HTMLDocument) 233 styleSheet = ((HTMLDocument) doc).getStyleSheet(); 234 return styleSheet; 235 } 236 237 /** 238 * Returns the minimum span for the specified axis. This returns the 239 * width of the longest word for the X axis and the super behaviour for 240 * the Y axis. This is a slight deviation from the reference implementation. 241 * IMO this should improve rendering behaviour so that an InlineView never 242 * gets smaller than the longest word in it. 243 */ 244 public float getMinimumSpan(int axis) 245 { 246 float min = super.getMinimumSpan(axis); 247 if (axis == X_AXIS) 248 min = Math.max(getLongestWord(), min); 249 return min; 250 } 251 252 /** 253 * Returns the span of the longest word in this view. 254 * 255 * @return the span of the longest word in this view 256 */ 257 private float getLongestWord() 258 { 259 if (longestWord == -1) 260 longestWord = calculateLongestWord(); 261 return longestWord; 262 } 263 264 /** 265 * Calculates the span of the longest word in this view. 266 * 267 * @return the span of the longest word in this view 268 */ 269 private float calculateLongestWord() 270 { 271 float span = 0; 272 try 273 { 274 Document doc = getDocument(); 275 int p0 = getStartOffset(); 276 int p1 = getEndOffset(); 277 Segment s = new Segment(); 278 doc.getText(p0, p1 - p0, s); 279 BreakIterator iter = BreakIterator.getWordInstance(); 280 iter.setText(s); 281 int wordStart = p0; 282 int wordEnd = p0; 283 int start = iter.first(); 284 for (int end = iter.next(); end != BreakIterator.DONE; 285 start = end, end = iter.next()) 286 { 287 if ((end - start) > (wordEnd - wordStart)) 288 { 289 wordStart = start; 290 wordEnd = end; 291 } 292 } 293 if (wordEnd - wordStart > 0) 294 { 295 FontMetrics fm = getFontMetrics(); 296 int offset = s.offset + wordStart - s.getBeginIndex(); 297 span = fm.charsWidth(s.array, offset, wordEnd - wordStart); 298 } 299 } 300 catch (BadLocationException ex) 301 { 302 // Return 0. 303 } 304 return span; 305 } 306 307}