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1   /**
2    * Licensed under the Artistic License; you may not use this file
3    * except in compliance with the License.
4    * You may obtain a copy of the License at
5    *
6    *      http://displaytag.sourceforge.net/license.html
7    *
8    * THIS PACKAGE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR
9    * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
10   * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
11   */
12  package org.displaytag.tags;
13  
14  import java.text.Collator;
15  import java.util.ArrayList;
16  import java.util.Comparator;
17  import java.util.List;
18  
19  import javax.servlet.http.HttpServletRequest;
20  import javax.servlet.http.HttpServletResponse;
21  import javax.servlet.jsp.JspException;
22  import javax.servlet.jsp.tagext.BodyTagSupport;
23  
24  import org.apache.commons.lang.StringUtils;
25  import org.apache.commons.lang.builder.ToStringBuilder;
26  import org.apache.commons.lang.builder.ToStringStyle;
27  import org.apache.commons.logging.Log;
28  import org.apache.commons.logging.LogFactory;
29  import org.displaytag.decorator.AutolinkColumnDecorator;
30  import org.displaytag.decorator.DisplaytagColumnDecorator;
31  import org.displaytag.decorator.EscapeXmlColumnDecorator;
32  import org.displaytag.decorator.MessageFormatColumnDecorator;
33  import org.displaytag.exception.DecoratorInstantiationException;
34  import org.displaytag.exception.InvalidTagAttributeValueException;
35  import org.displaytag.exception.ObjectLookupException;
36  import org.displaytag.exception.TagStructureException;
37  import org.displaytag.model.Cell;
38  import org.displaytag.model.DefaultComparator;
39  import org.displaytag.model.HeaderCell;
40  import org.displaytag.properties.MediaTypeEnum;
41  import org.displaytag.properties.SortOrderEnum;
42  import org.displaytag.util.DefaultHref;
43  import org.displaytag.util.Href;
44  import org.displaytag.util.HtmlAttributeMap;
45  import org.displaytag.util.MediaUtil;
46  import org.displaytag.util.MultipleHtmlAttribute;
47  import org.displaytag.util.TagConstants;
48  
49  
50  /**
51   * <p>
52   * This tag works hand in hand with the TableTag to display a list of objects. This describes a column of data in the
53   * TableTag. There can be any number of columns that make up the list.
54   * </p>
55   * <p>
56   * This tag does no work itself, it is simply a container of information. The TableTag does all the work based on the
57   * information provided in the attributes of this tag.
58   * <p>
59   * @author mraible
60   * @author Fabrizio Giustina
61   * @version $Revision: 1097 $ ($Author: rapruitt $)
62   */
63  public class ColumnTag extends BodyTagSupport implements MediaUtil.SupportsMedia
64  {
65  
66      /**
67       * D1597A17A6.
68       */
69      private static final long serialVersionUID = 899149338534L;
70  
71      /**
72       * logger.
73       */
74      private static Log log = LogFactory.getLog(ColumnTag.class);
75  
76      /**
77       * html pass-through attributes for cells.
78       */
79      private HtmlAttributeMap attributeMap = new HtmlAttributeMap();
80  
81      /**
82       * html pass-through attributes for cell headers.
83       */
84      private HtmlAttributeMap headerAttributeMap = new HtmlAttributeMap();
85  
86      /**
87       * the property method that is called to retrieve the information to be displayed in this column. This method is
88       * called on the current object in the iteration for the given row. The property format is in typical struts format
89       * for properties (required)
90       */
91      private String property;
92  
93      /**
94       * the title displayed for this column. if this is omitted then the property name is used for the title of the
95       * column (optional).
96       */
97      private String title;
98  
99      /**
100      * by default, null values don't appear in the list, by setting viewNulls to 'true', then null values will appear as
101      * "null" in the list (mostly useful for debugging) (optional).
102      */
103     private boolean nulls;
104 
105     /**
106      * is the column sortable?
107      */
108     private boolean sortable;
109 
110     /**
111      * Name given to the server when sorting this column.
112      */
113     private String sortName;
114 
115     /**
116      * Defalt sort order for this column.
117      */
118     private SortOrderEnum defaultorder;
119 
120     /**
121      * The comparator to use when sorting this column.
122      */
123     private Comparator comparator;
124 
125     /**
126      * if set to true, then any email addresses and URLs found in the content of the column are automatically converted
127      * into a hypertext link.
128      */
129     private boolean autolink;
130 
131     /**
132      * Automatically escape column content for html and xml media.
133      */
134     private boolean escapeXml;
135 
136     /**
137      * A MessageFormat patter that will be used to decorate objects in the column. Can be used as a "shortcut" for
138      * simple column decorations.
139      */
140     private String format;
141 
142     /**
143      * the grouping level (starting at 1 and incrementing) of this column (indicates if successive contain the same
144      * values, then they should not be displayed). The level indicates that if a lower level no longer matches, then the
145      * matching for this higher level should start over as well. If this attribute is not included, then no grouping is
146      * performed. (optional)
147      */
148     private int group = -1;
149 
150     /**
151      * if this attribute is provided, then the data that is shown for this column is wrapped inside a &lt;a href&gt; tag
152      * with the url provided through this attribute. Typically you would use this attribute along with one of the
153      * struts-like param attributes below to create a dynamic link so that each row creates a different URL based on the
154      * data that is being viewed. (optional)
155      */
156     private Href href;
157 
158     /**
159      * The name of the request parameter that will be dynamically added to the generated href URL. The corresponding
160      * value is defined by the paramProperty and (optional) paramName attributes, optionally scoped by the paramScope
161      * attribute. (optional)
162      */
163     private String paramId;
164 
165     /**
166      * The name of a JSP bean that is a String containing the value for the request parameter named by paramId (if
167      * paramProperty is not specified), or a JSP bean whose property getter is called to return a String (if
168      * paramProperty is specified). The JSP bean is constrained to the bean scope specified by the paramScope property,
169      * if it is specified. If paramName is omitted, then it is assumed that the current object being iterated on is the
170      * target bean. (optional)
171      */
172     private String paramName;
173 
174     /**
175      * The name of a property of the bean specified by the paramName attribute (or the current object being iterated on
176      * if paramName is not provided), whose return value must be a String containing the value of the request parameter
177      * (named by the paramId attribute) that will be dynamically added to this href URL. (optional)
178      * @deprecated use Expressions in paramName
179      */
180     private String paramProperty;
181 
182     /**
183      * The scope within which to search for the bean specified by the paramName attribute. If not specified, all scopes
184      * are searched. If paramName is not provided, then the current object being iterated on is assumed to be the target
185      * bean. (optional)
186      * @deprecated use Expressions in paramName
187      */
188     private String paramScope;
189 
190     /**
191      * If this attribute is provided, then the column's displayed is limited to this number of characters. An elipse
192      * (...) is appended to the end if this column is linked, and the user can mouseover the elipse to get the full
193      * text. (optional)
194      */
195     private int maxLength;
196 
197     /**
198      * If this attribute is provided, then the column's displayed is limited to this number of words. An elipse (...) is
199      * appended to the end if this column is linked, and the user can mouseover the elipse to get the full text.
200      * (optional)
201      */
202     private int maxWords;
203 
204     /**
205      * a class that should be used to "decorate" the underlying object being displayed. If a decorator is specified for
206      * the entire table, then this decorator will decorate that decorator. (optional)
207      */
208     private String decorator;
209 
210     /**
211      * is the column already sorted?
212      */
213     private boolean alreadySorted;
214 
215     /**
216      * The media supported attribute.
217      */
218     private List supportedMedia;
219 
220     /**
221      * Property in a resource bundle to be used as the title for the column.
222      */
223     private String titleKey;
224 
225     /**
226      * The name of the bean property if a decorator is used and sorting need to be still on on the property itself.
227      * Useful for displaying data with links but sorting on original value.
228      */
229     private String sortProperty;
230 
231     /**
232      * Should the value of the column be summed? Requires that the value of the column be convertible to a Number.
233      */
234     private boolean totaled;
235 
236     /**
237      * Static value for this cell, equivalent to column body.
238      */
239     private Object value;
240 
241     /**
242      * Setter for totals.
243      * @param totals the value
244      */
245     public void setTotal(boolean totals)
246     {
247         this.totaled = totals;
248     }
249 
250     /**
251      * setter for the "property" tag attribute.
252      * @param value attribute value
253      */
254     public void setProperty(String value)
255     {
256         this.property = value;
257     }
258 
259     /**
260      * setter for the "value" tag attribute.
261      * @param value attribute value
262      */
263     public void setValue(Object value)
264     {
265         this.value = value;
266     }
267 
268     /**
269      * Set the comparator, classname or object.
270      * @param comparatorObj the comparator, classname or object
271      */
272     public void setComparator(Object comparatorObj)
273     {
274         // @todo don't do this! Setters should remains simple setters and any evaluation should be done in doEndTag()!
275         if (comparatorObj instanceof Comparator)
276         {
277             this.comparator = (Comparator) comparatorObj;
278         }
279         else if (comparatorObj instanceof String)
280         {
281             String comparatorClassname = (String) comparatorObj;
282             Class compClass;
283             try
284             {
285                 compClass = Thread.currentThread().getContextClassLoader().loadClass(comparatorClassname);
286             }
287             catch (ClassNotFoundException e)
288             {
289                 throw new RuntimeException("InstantiationException setting column comparator as "
290                     + comparatorClassname
291                     + ": "
292                     + e.getMessage(), e);
293             }
294             try
295             {
296                 this.comparator = (Comparator) compClass.newInstance();
297             }
298             catch (InstantiationException e)
299             {
300                 throw new RuntimeException("InstantiationException setting column comparator as "
301                     + comparatorClassname
302                     + ": "
303                     + e.getMessage(), e);
304             }
305             catch (IllegalAccessException e)
306             {
307                 throw new RuntimeException("IllegalAccessException setting column comparator as "
308                     + comparatorClassname
309                     + ": "
310                     + e.getMessage(), e);
311             }
312         }
313         else
314         {
315             throw new IllegalArgumentException("Value for comparator: "
316                 + comparatorObj
317                 + " of type "
318                 + comparatorObj.getClass().getName());
319         }
320     }
321 
322     /**
323      * setter for the "title" tag attribute.
324      * @param value attribute value
325      */
326     public void setTitle(String value)
327     {
328         this.title = value;
329     }
330 
331     /**
332      * setter for the "format" tag attribute.
333      * @param value attribute value
334      */
335     public void setFormat(String value)
336     {
337         this.format = value;
338     }
339 
340     /**
341      * setter for the "nulls" tag attribute.
342      * @param value attribute value
343      */
344     public void setNulls(boolean value)
345     {
346         this.nulls = value;
347     }
348 
349     /**
350      * setter for the "sortable" tag attribute.
351      * @param value attribute value
352      */
353     public void setSortable(boolean value)
354     {
355         this.sortable = value;
356     }
357 
358     /**
359      * setter for the "autolink" tag attribute.
360      * @param value attribute value
361      */
362     public void setAutolink(boolean value)
363     {
364         this.autolink = value;
365     }
366 
367     /**
368      * setter for the "escapeXml" tag attribute.
369      * @param value attribute value
370      */
371     public void setEscapeXml(boolean value)
372     {
373         this.escapeXml = value;
374     }
375 
376     /**
377      * setter for the "group" tag attribute.
378      * @param value attribute value
379      */
380     public void setGroup(int value)
381     {
382         this.group = value;
383     }
384 
385     /**
386      * setter for the "titleKey" tag attribute.
387      * @param value property name
388      */
389     public void setTitleKey(String value)
390     {
391         this.titleKey = value;
392     }
393 
394     /**
395      * setter for the "href" tag attribute.
396      * @param value attribute value
397      */
398     public void setHref(String value)
399     {
400         // call encodeURL to preserve session id when cookies are disabled
401         String encodedHref = ((HttpServletResponse) this.pageContext.getResponse()).encodeURL(StringUtils
402             .defaultString(value));
403         this.href = new DefaultHref(encodedHref);
404     }
405 
406     /**
407      * setter for the "url" tag attribute. This has the same meaning of href, but prepends the context path to the given
408      * URI.
409      * @param value attribute value
410      */
411     public void setUrl(String value)
412     {
413         HttpServletRequest req = (HttpServletRequest) pageContext.getRequest();
414         // call encodeURL to preserve session id when cookies are disabled
415         String encodedHref = ((HttpServletResponse) this.pageContext.getResponse()).encodeURL(StringUtils
416             .defaultString(req.getContextPath() + value));
417         this.href = new DefaultHref(encodedHref);
418     }
419 
420     /**
421      * setter for the "paramId" tag attribute.
422      * @param value attribute value
423      */
424     public void setParamId(String value)
425     {
426         this.paramId = value;
427     }
428 
429     /**
430      * setter for the "paramName" tag attribute.
431      * @param value attribute value
432      */
433     public void setParamName(String value)
434     {
435         this.paramName = value;
436     }
437 
438     /**
439      * setter for the "paramProperty" tag attribute.
440      * @param value attribute value
441      */
442     public void setParamProperty(String value)
443     {
444         this.paramProperty = value;
445     }
446 
447     /**
448      * setter for the "paramScope" tag attribute.
449      * @param value attribute value
450      */
451     public void setParamScope(String value)
452     {
453         this.paramScope = value;
454     }
455 
456     /**
457      * setter for the "scope" tag attribute.
458      * @param value attribute value
459      */
460     public void setScope(String value)
461     {
462         this.attributeMap.put(TagConstants.ATTRIBUTE_SCOPE, value);
463     }
464 
465     /**
466      * setter for the "headerScope" tag attribute.
467      * @param value attribute value
468      */
469     public void setHeaderScope(String value)
470     {
471         this.headerAttributeMap.put(TagConstants.ATTRIBUTE_SCOPE, value);
472     }
473 
474     /**
475      * setter for the "maxLength" tag attribute.
476      * @param value attribute value
477      */
478     public void setMaxLength(int value)
479     {
480         this.maxLength = value;
481     }
482 
483     /**
484      * setter for the "maxWords" tag attribute.
485      * @param value attribute value
486      */
487     public void setMaxWords(int value)
488     {
489         this.maxWords = value;
490     }
491 
492     /**
493      * setter for the "style" tag attribute.
494      * @param value attribute value
495      */
496     public void setStyle(String value)
497     {
498         this.attributeMap.put(TagConstants.ATTRIBUTE_STYLE, value);
499     }
500 
501     /**
502      * setter for the "class" tag attribute.
503      * @param value attribute value
504      */
505     public void setClass(String value)
506     {
507         this.attributeMap.put(TagConstants.ATTRIBUTE_CLASS, new MultipleHtmlAttribute(value));
508     }
509 
510     /**
511      * setter for the "headerClass" tag attribute.
512      * @param value attribute value
513      */
514     public void setHeaderClass(String value)
515     {
516         this.headerAttributeMap.put(TagConstants.ATTRIBUTE_CLASS, new MultipleHtmlAttribute(value));
517     }
518 
519     /**
520      * setter for the "decorator" tag attribute.
521      * @param value attribute value
522      */
523     public void setDecorator(String value)
524     {
525         this.decorator = value;
526     }
527 
528     /**
529      * setter for the "sortProperty" tag attribute.
530      * @param value attribute value
531      */
532     public void setSortProperty(String value)
533     {
534         this.sortProperty = value;
535     }
536 
537     /**
538      * Looks up the parent table tag.
539      * @return a table tag instance.
540      */
541     protected TableTag getTableTag()
542     {
543         return (TableTag) findAncestorWithClass(this, TableTag.class);
544     }
545 
546     /**
547      * Tag setter.
548      * @param media the space delimited list of supported types
549      */
550     public void setMedia(String media)
551     {
552         MediaUtil.setMedia(this, media);
553     }
554 
555     /**
556      * @see org.displaytag.util.MediaUtil.SupportsMedia#setSupportedMedia(java.util.List)
557      */
558     public void setSupportedMedia(List media)
559     {
560         this.supportedMedia = media;
561     }
562 
563     /**
564      * @see org.displaytag.util.MediaUtil.SupportsMedia#getSupportedMedia()
565      */
566     public List getSupportedMedia()
567     {
568         return this.supportedMedia;
569     }
570 
571     /**
572      * sets the name given to the server when sorting this column
573      * @param sortName name given to the server to sort this column
574      */
575     public void setSortName(String sortName)
576     {
577         this.sortName = sortName;
578     }
579 
580     /**
581      * sets the sorting order for the sorted column.
582      * @param value "ascending" or "descending"
583      * @throws InvalidTagAttributeValueException if value is not one of "ascending" or "descending"
584      */
585     public void setDefaultorder(String value) throws InvalidTagAttributeValueException
586     {
587         this.defaultorder = SortOrderEnum.fromName(value);
588         if (this.defaultorder == null)
589         {
590             throw new InvalidTagAttributeValueException(getClass(), "defaultorder", value); //$NON-NLS-1$
591         }
592     }
593 
594     /**
595      * Passes attribute information up to the parent TableTag.
596      * <p>
597      * When we hit the end of the tag, we simply let our parent (which better be a TableTag) know what the user wants to
598      * do with this column. We do that by simple registering this tag with the parent. This tag's only job is to hold
599      * the configuration information to describe this particular column. The TableTag does all the work.
600      * </p>
601      * @return int
602      * @throws JspException if this tag is being used outside of a &lt;display:list...&gt; tag.
603      * @see javax.servlet.jsp.tagext.Tag#doEndTag()
604      */
605     public int doEndTag() throws JspException
606     {
607         TableTag tableTag = getTableTag();
608 
609         MediaTypeEnum currentMediaType = (MediaTypeEnum) this.pageContext.findAttribute(TableTag.PAGE_ATTRIBUTE_MEDIA);
610         if (currentMediaType != null && !MediaUtil.availableForMedia(this, currentMediaType))
611         {
612             if (log.isDebugEnabled())
613             {
614                 log.debug("skipping column body, currentMediaType=" + currentMediaType);
615             }
616             return SKIP_BODY;
617         }
618 
619         // add column header only once
620         if (tableTag.isFirstIteration())
621         {
622             addHeaderToTable(tableTag);
623         }
624 
625         if (!tableTag.isIncludedRow())
626         {
627             return super.doEndTag();
628         }
629 
630         Cell cell = null;
631         if (this.property == null && this.value != null)
632         {
633             cell = new Cell(value);
634         }
635         else if (this.property == null && this.bodyContent != null)
636         {
637             cell = new Cell(this.bodyContent.getString());
638         }
639 
640         Object rowStyle = this.attributeMap.get(TagConstants.ATTRIBUTE_STYLE);
641         Object rowClass = this.attributeMap.get(TagConstants.ATTRIBUTE_CLASS);
642         if (rowStyle != null || rowClass != null)
643         {
644             HtmlAttributeMap perRowValues = new HtmlAttributeMap();
645             if (rowStyle != null)
646             {
647                 perRowValues.put(TagConstants.ATTRIBUTE_STYLE, rowStyle);
648             }
649             if (rowClass != null)
650             {
651                 perRowValues.put(TagConstants.ATTRIBUTE_CLASS, rowClass);
652             }
653             if (cell == null)
654             {
655                 cell = new Cell(null);
656             }
657             cell.setPerRowAttributes(perRowValues);
658         }
659 
660         tableTag.addCell(cell != null ? cell : Cell.EMPTY_CELL);
661 
662         // cleanup non-attribute variables
663         this.alreadySorted = false;
664 
665         return super.doEndTag();
666     }
667 
668     /**
669      * Adds the current header to the table model calling addColumn in the parent table tag. This method should be
670      * called only at first iteration.
671      * @param tableTag parent table tag
672      * @throws DecoratorInstantiationException for error during column decorator instantiation
673      * @throws ObjectLookupException for errors in looking up values
674      */
675     private void addHeaderToTable(TableTag tableTag) throws DecoratorInstantiationException, ObjectLookupException
676     {
677         // don't modify "title" directly
678         String evalTitle = this.title;
679 
680         // title has precedence over titleKey
681         if (evalTitle == null && (this.titleKey != null || this.property != null))
682         {
683             // handle title i18n
684             evalTitle = tableTag.getProperties().geResourceProvider().getResource(
685                 this.titleKey,
686                 this.property,
687                 tableTag,
688                 this.pageContext);
689         }
690 
691         HeaderCell headerCell = new HeaderCell();
692         headerCell.setHeaderAttributes((HtmlAttributeMap) this.headerAttributeMap.clone());
693         headerCell.setHtmlAttributes((HtmlAttributeMap) this.attributeMap.clone());
694         headerCell.setTitle(evalTitle);
695         headerCell.setSortable(this.sortable);
696 
697         List decorators = new ArrayList();
698 
699         // handle multiple chained decorators, whitespace separated
700         if (StringUtils.isNotEmpty(this.decorator))
701         {
702             String[] decoratorNames = StringUtils.split(this.decorator);
703             for (int j = 0; j < decoratorNames.length; j++)
704             {
705                 decorators.add(tableTag.getProperties().getDecoratorFactoryInstance().loadColumnDecorator(
706                     this.pageContext,
707                     decoratorNames[j]));
708             }
709         }
710 
711         // "special" decorators
712         if (this.escapeXml)
713         {
714             decorators.add(EscapeXmlColumnDecorator.INSTANCE);
715         }
716         if (this.autolink)
717         {
718             decorators.add(AutolinkColumnDecorator.INSTANCE);
719         }
720         if (StringUtils.isNotBlank(this.format))
721         {
722             decorators.add(new MessageFormatColumnDecorator(this.format, tableTag.getProperties().getLocale()));
723         }
724 
725         headerCell.setColumnDecorators((DisplaytagColumnDecorator[]) decorators
726             .toArray(new DisplaytagColumnDecorator[decorators.size()]));
727 
728         headerCell.setBeanPropertyName(this.property);
729         headerCell.setShowNulls(this.nulls);
730         headerCell.setMaxLength(this.maxLength);
731         headerCell.setMaxWords(this.maxWords);
732         headerCell.setGroup(this.group);
733         headerCell.setSortProperty(this.sortProperty);
734         headerCell.setTotaled(this.totaled);
735 
736         Comparator headerComparator = (comparator != null) ? comparator : tableTag.getProperties().getDefaultComparator();
737 
738         headerCell.setComparator(headerComparator);
739         headerCell.setDefaultSortOrder(this.defaultorder);
740         headerCell.setSortName(this.sortName);
741 
742         // href and parameter, create link
743         if (this.href != null)
744         {
745             Href colHref;
746 
747             // empty base url, use href with parameters from parent table
748             if (StringUtils.isEmpty(this.href.getBaseUrl()))
749             {
750                 colHref = (Href) tableTag.getBaseHref().clone();
751             }
752             else
753             {
754                 colHref = (Href) this.href.clone();
755             }
756 
757             if (this.paramId != null)
758             {
759                 // parameter value is in a different object than the iterated one
760                 if (this.paramName != null || this.paramScope != null)
761                 {
762                     // create a complete string for compatibility with previous version before expression evaluation.
763                     // this approach is optimized for new expressions, not for previous property/scope parameters
764                     StringBuffer expression = new StringBuffer();
765 
766                     // append scope
767                     if (StringUtils.isNotBlank(this.paramScope))
768                     {
769                         expression.append(this.paramScope).append("Scope.");
770                     }
771 
772                     // base bean name
773                     if (this.paramId != null)
774                     {
775                         expression.append(this.paramName);
776                     }
777                     else
778                     {
779                         expression.append(tableTag.getName());
780                     }
781 
782                     // append property
783                     if (StringUtils.isNotBlank(this.paramProperty))
784                     {
785                         expression.append('.').append(this.paramProperty);
786                     }
787 
788                     // evaluate expression.
789                     // note the value is fixed, not based on any object created during iteration
790                     // this is here for compatibility with the old version mainly
791                     Object paramValue = tableTag.evaluateExpression(expression.toString());
792 
793                     // add parameter
794                     colHref.addParameter(this.paramId, paramValue);
795                 }
796                 else
797                 {
798                     // set id
799                     headerCell.setParamName(this.paramId);
800 
801                     // set property
802                     headerCell.setParamProperty(this.paramProperty);
803                 }
804             }
805 
806             // sets the base href
807             headerCell.setHref(colHref);
808 
809         }
810 
811         tableTag.addColumn(headerCell);
812 
813         if (log.isDebugEnabled())
814         {
815             log.debug("columnTag.addHeaderToTable() :: first iteration - adding header " + headerCell);
816         }
817     }
818 
819     /**
820      * @see javax.servlet.jsp.tagext.Tag#release()
821      */
822     public void release()
823     {
824         super.release();
825         this.attributeMap.clear();
826         this.autolink = false;
827         this.decorator = null;
828         this.group = -1;
829         this.headerAttributeMap.clear();
830         this.href = null;
831         this.maxLength = 0;
832         this.maxWords = 0;
833         this.nulls = false;
834         this.paramId = null;
835         this.paramName = null;
836         this.paramProperty = null;
837         this.paramScope = null;
838         this.property = null;
839         this.sortable = false;
840         this.sortName = null;
841         this.supportedMedia = null;
842         this.title = null;
843         this.titleKey = null;
844         this.sortProperty = null;
845         this.comparator = null;
846         this.defaultorder = null;
847         this.escapeXml = false;
848         this.format = null;
849         this.value = null;
850         this.totaled = false;
851     }
852 
853     /**
854      * @see javax.servlet.jsp.tagext.Tag#doStartTag()
855      */
856     public int doStartTag() throws JspException
857     {
858         TableTag tableTag = getTableTag();
859         if (tableTag == null)
860         {
861             throw new TagStructureException(getClass(), "column", "table");
862         }
863 
864         // If the list is empty, do not execute the body; may result in NPE
865         if (tableTag.isEmpty() || !tableTag.isIncludedRow())
866         {
867             return SKIP_BODY;
868         }
869 
870         MediaTypeEnum currentMediaType = (MediaTypeEnum) this.pageContext.findAttribute(TableTag.PAGE_ATTRIBUTE_MEDIA);
871         if (!MediaUtil.availableForMedia(this, currentMediaType))
872         {
873             return SKIP_BODY;
874         }
875 
876         return super.doStartTag();
877     }
878 
879     /**
880      * @see java.lang.Object#toString()
881      */
882     public String toString()
883     {
884         return new ToStringBuilder(this, ToStringStyle.SHORT_PREFIX_STYLE) //
885             .append("bodyContent", this.bodyContent) //$NON-NLS-1$
886             .append("group", this.group) //$NON-NLS-1$
887             .append("maxLength", this.maxLength) //$NON-NLS-1$
888             .append("decorator", this.decorator) //$NON-NLS-1$
889             .append("href", this.href) //$NON-NLS-1$
890             .append("title", this.title) //$NON-NLS-1$
891             .append("paramScope", this.paramScope) //$NON-NLS-1$
892             .append("property", this.property) //$NON-NLS-1$
893             .append("paramProperty", this.paramProperty) //$NON-NLS-1$
894             .append("headerAttributeMap", this.headerAttributeMap) //$NON-NLS-1$
895             .append("paramName", this.paramName) //$NON-NLS-1$
896             .append("autolink", this.autolink) //$NON-NLS-1$
897             .append("format", this.format) //$NON-NLS-1$
898             .append("nulls", this.nulls) //$NON-NLS-1$
899             .append("maxWords", this.maxWords) //$NON-NLS-1$
900             .append("attributeMap", this.attributeMap) //$NON-NLS-1$
901             .append("sortable", this.sortable) //$NON-NLS-1$
902             .append("paramId", this.paramId) //$NON-NLS-1$
903             .append("alreadySorted", this.alreadySorted) //$NON-NLS-1$
904             .append("sortProperty", this.sortProperty) //$NON-NLS-1$
905             .append("defaultSortOrder", this.defaultorder) //$NON-NLS-1$
906             .toString();
907     }
908 
909 }