001 package edu.nrao.sss.html;
002
003 import java.io.IOException;
004 import java.io.Writer;
005 import java.util.HashMap;
006 import java.util.Map;
007
008 import javax.swing.text.html.HTML;
009
010 /**
011 * A cell in an HTML table.
012 * <p>
013 * <b>Version Info:</b>
014 * <table style="margin-left:2em">
015 * <tr><td>$Revision: 545 $</td></tr>
016 * <tr><td>$Date: 2007-04-19 10:38:45 -0600 (Thu, 19 Apr 2007) $</td></tr>
017 * <tr><td>$Author: dharland $</td></tr>
018 * </table></p>
019 *
020 * @author David M. Harland
021 * @since 2007-03-15
022 */
023 public class HtmlTableCell
024 extends HtmlElement
025 implements Cloneable
026 {
027 Type type;
028 HtmlTableRow parentRow; //Not directly publicly mutable
029 StringBuilder unparsedContents;
030
031 /** Creates a new data cell. */
032 public HtmlTableCell()
033 {
034 this(Type.DATA);
035 }
036
037 /**
038 * Creates a new data cell with the given contents.
039 * @param contents the contents of this cell.
040 */
041 public HtmlTableCell(String contents)
042 {
043 this(Type.DATA);
044
045 unparsedContents.append(contents);
046 }
047
048 /**
049 * Creates a new cell of the given type.
050 *
051 * @param cellType the type of this cell, either data or header.
052 * If this value is <i>null</i>, this cell will
053 * be a data cell.
054 */
055 public HtmlTableCell(Type cellType)
056 {
057 super(HTML.Tag.TD);
058
059 setType(cellType); //tag c/b reset here
060
061 parentRow = null;
062 unparsedContents = new StringBuilder();
063 }
064
065 /**
066 * Creates a new {@code cellType} cell with the given contents.
067 *
068 * @param cellType the type of this cell, either data or header.
069 * If this value is <i>null</i>, this cell will
070 * be a data cell.
071 *
072 * @param contents the contents of this cell.
073 */
074 public HtmlTableCell(Type cellType, String contents)
075 {
076 this(cellType);
077
078 unparsedContents.append(contents);
079 }
080
081 //============================================================================
082 //
083 //============================================================================
084
085 /** Returns <i>false</i>. */
086 @Override
087 public boolean isSimple() { return false; }
088
089 /**
090 * Returns the row to which this cell belongs.
091 *
092 * @return the row to which this cell belongs.
093 * If this cell does not belong to a row, the returned
094 * value will be <i>null</i>.
095 */
096 public HtmlTableRow getParentRow()
097 {
098 return parentRow;
099 }
100
101 /**
102 * Returns the position of this cell in its row.
103 * The first position is zero.
104 *
105 * @return the position of this cell in its row.
106 * If this cell is not part of a row, the
107 * value returned is -1.
108 */
109 public int getPositionInRow()
110 {
111 return (parentRow == null) ? -1 : parentRow.cells.indexOf(this);
112 }
113
114 /**
115 * Sets the type of this cell.
116 *
117 * @param newType the type of this cell. If this value is <i>null</i>,
118 * this cell will be set to a data cell.
119 */
120 public final void setType(Type newType)
121 {
122 type = (newType == null) ? Type.DATA : newType;
123
124 if (type.equals(Type.DATA )) tag = HTML.Tag.TD;
125 else if (type.equals(Type.HEADER)) tag = HTML.Tag.TH;
126 else
127 throw new RuntimeException("PROGRAMMER ERROR: " +
128 "No HTML.Tag mapping for unknown HtmlTableCell.Type = " + type);
129 }
130
131 /**
132 * Returns the type of this cell.
133 * @return the type of this cell.
134 */
135 public Type getType()
136 {
137 return type;
138 }
139
140 /**
141 * Returns the contents between the beginning and ending cell tags.
142 *
143 * @return the contents between the beginning and ending cell tags.
144 * The value returned is guaranteed to be non-null, but could
145 * be empty. It is also the object held internally by this
146 * cell, so any alterations to it will be reflected herein.
147 */
148 public StringBuilder getUnparsedContents()
149 {
150 return unparsedContents;
151 }
152
153 /**
154 * Returns the number of columns spanned by this cell.
155 * @return the number of columns spanned by this cell.
156 */
157 public int getColumnSpan()
158 {
159 return getSpan(getAttributeValue(HTML.Attribute.COLSPAN));
160 }
161
162 /**
163 * Returns the number of rows spanned by this cell.
164 * @return the number of rows spanned by this cell.
165 */
166 public int getRowSpan()
167 {
168 return getSpan(getAttributeValue(HTML.Attribute.ROWSPAN));
169 }
170
171 /** Does the work for getColumnSpan & getRowSpan. */
172 private int getSpan(String text)
173 {
174 int span;
175
176 if (text.length() > 0)
177 {
178 try {
179 span = Integer.parseInt(text);
180 }
181 catch (NumberFormatException ex) {
182 span = 1;
183 }
184 }
185 else
186 {
187 span = 1;
188 }
189
190 return span;
191 }
192
193 /**
194 * Returns the numeric value of the width attribute of this cell.
195 * If this cell has no width attribute, the value returned is -1.
196 *
197 * @return the numeric value of the width attribute of this cell, or -1 if
198 * this cell has no width magnitude.
199 */
200 public int getWidthMagnitude()
201 {
202 String widthText = getAttributeValue(HTML.Attribute.WIDTH);
203
204 int value;
205
206 try
207 { // \D means "non-digit"
208 value = Integer.parseInt(widthText.replaceAll("\\D", "").trim());
209 }
210 catch (NumberFormatException ex)
211 {
212 value = -1;
213 }
214
215 return value;
216 }
217
218 /**
219 * Returns the portion of this cell's width attribute that follows
220 * the numeric portion. For example, if this cell has
221 * <tt>width="25%"</tt>, the value returned is "%". If this cell has no
222 * width attribute, the value returned is the empty string (<tt>""</tt>).
223 * (Note that the empty string would also be returned if this cell
224 * has <tt>width="3"</tt>.)
225 * <p>
226 * <b>Note:</b> the algorithm used by this method assumes that the value
227 * of the width attribute, if present, is properly formed. If it is not,
228 * the results of this method are unpredictable.</p>
229 *
230 * @return the portion of this cell's width attribute that follows the numeric
231 * portion, or the empty string if this cell has no width attribute.
232 */
233 public String getWidthSuffix()
234 {
235 String widthText = getAttributeValue(HTML.Attribute.WIDTH);
236
237 return widthText.replaceAll("\\d", "").trim(); // \d means "digit"
238 }
239
240 //============================================================================
241 // WRITING
242 //============================================================================
243
244 @Override
245 void writeContentsAsHtml(Writer device, int padding, int depth) throws IOException
246 {
247 //java's HTML parser converts to character 0xA0; reverse this
248 StringBuilder buff = new StringBuilder(unparsedContents);
249
250 replaceUnicodeNbspWith(buff, NBSP_HTML);
251
252 device.write(buff.toString());
253 }
254
255 //============================================================================
256 //
257 //============================================================================
258
259 /** Returns <i>true</i> if {@code o} is equal to this cell. */
260 @Override
261 public boolean equals(Object o)
262 {
263 //Quick exit if o is this
264 if (o == this)
265 return true;
266
267 //Quick exit if o is null
268 if (o == null)
269 return false;
270
271 //Quick exit if classes are different
272 if (!o.getClass().equals(this.getClass()))
273 return false;
274
275 HtmlTableCell other = (HtmlTableCell)o;
276
277 //Intential absence of: parentRow
278
279 return this.type.equals(other.type) &&
280 this.attributes.equals(other.attributes) &&
281 this.unparsedContents.toString()
282 .equals(other.unparsedContents.toString());
283 }
284
285 /**
286 * Compares {@code other} to this cell for equality, ignoring the
287 * <tt>parentRow</tt> and the <tt>colspan</tt> and <tt>rowspan</tt>
288 * attributes.
289 *
290 * @param other the cell to which the comparison is made.
291 *
292 * @return <i>true</i> if {@code other} is equal to this one, according
293 * to the definition above.
294 */
295 public boolean equalsIgnoreSpans(HtmlTableCell other)
296 {
297 //Compare everything but the attributes
298 if (!this.type.equals(other.type) ||
299 !this.unparsedContents.toString().
300 equals(other.unparsedContents.toString()))
301 return false;
302
303 //Remove COLSPAN & ROWSPAN, then compare remaining attributes
304 Map<HTML.Attribute, HtmlAttribute> thisAttr =
305 new HashMap<HTML.Attribute, HtmlAttribute>(this.attributes);
306
307 Map<HTML.Attribute, HtmlAttribute> otherAttr =
308 new HashMap<HTML.Attribute, HtmlAttribute>(other.attributes);
309
310 thisAttr.remove(HTML.Attribute.COLSPAN);
311 otherAttr.remove(HTML.Attribute.COLSPAN);
312
313 thisAttr.remove(HTML.Attribute.ROWSPAN);
314 otherAttr.remove(HTML.Attribute.ROWSPAN);
315
316 return thisAttr.equals(otherAttr);
317 }
318
319 /**
320 * Compares {@code other} to this cell for equality, ignoring the
321 * <tt>parentRow</tt> and {@code attribute}.
322 *
323 * @param other the cell to which the comparison is made.
324 * @param attribute the attribute to ignore in the comparison.
325 * @return <i>true</i> if {@code other} is equal to this one, according
326 * to the definition above.
327 */
328 public boolean equalsIgnoreAttribute(HtmlTableCell other,
329 HTML.Attribute attribute)
330 {
331 //Compare everything but the attributes
332 if (!this.type.equals(other.type) ||
333 !this.unparsedContents.toString()
334 .equals(other.unparsedContents.toString()))
335 return false;
336
337 //Remove attribute, then compare remaining attributes
338 Map<HTML.Attribute, HtmlAttribute> thisAttr =
339 new HashMap<HTML.Attribute, HtmlAttribute>(this.attributes);
340
341 Map<HTML.Attribute, HtmlAttribute> otherAttr =
342 new HashMap<HTML.Attribute, HtmlAttribute>(other.attributes);
343
344 thisAttr.remove(attribute);
345 otherAttr.remove(attribute);
346
347 return thisAttr.equals(otherAttr);
348 }
349
350 /** Returns a hash code value for this cell. */
351 @Override
352 public int hashCode()
353 {
354 //Taken from the Effective Java book by Joshua Bloch.
355 //The constants 17 & 37 are arbitrary & carry no meaning.
356 int result = 17;
357
358 //You MUST keep this method in synch w/ equals
359
360 result = 37 * result + type.hashCode();
361 result = 37 * result + attributes.hashCode();
362 result = 37 * result + unparsedContents.hashCode();
363
364 return result;
365 }
366
367 /**
368 * Returns a new copy of this cell.
369 * The copy is almost a deep copy. The one exception is that
370 * the <tt>parentRow</tt> of the returned clone is <i>null</i>.
371 * <p>
372 * If anything goes wrong during the cloning procedure,
373 * a {@code RuntimeException} will be thrown.</p>
374 */
375 @Override
376 public HtmlTableCell clone()
377 {
378 HtmlTableCell clone = null;
379
380 try
381 {
382 clone = (HtmlTableCell)super.clone();
383
384 clone.parentRow = null;
385 clone.unparsedContents = new StringBuilder(this.unparsedContents);
386 clone.attributes =
387 new HashMap<HTML.Attribute, HtmlAttribute>(this.attributes);
388 }
389 catch (Exception ex)
390 {
391 throw new RuntimeException(ex);
392 }
393
394 return clone;
395 }
396
397 //============================================================================
398 //
399 //============================================================================
400
401 /** Types of table cells. */
402 public enum Type
403 {
404 /**
405 * A header cell. Corresponds to {@link javax.swing.text.html.HTML.Tag#TH}.
406 */
407 HEADER,
408
409 /**
410 * A data cell. Corresponds to {@link javax.swing.text.html.HTML.Tag#TD}.
411 */
412 DATA;
413 }
414 }