001    /*
002     * Licensed to the Apache Software Foundation (ASF) under one
003     * or more contributor license agreements. See the NOTICE file
004     * distributed with this work for additional information
005     * regarding copyright ownership. The ASF licenses this file
006     * to you under the Apache License, Version 2.0 (the  "License");
007     * you may not use this file except in compliance with the License.
008     * You may obtain a copy of the License at
009     *
010     *     http://www.apache.org/licenses/LICENSE-2.0
011     *
012     * Unless required by applicable law or agreed to in writing, software
013     * distributed under the License is distributed on an "AS IS" BASIS,
014     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015     * See the License for the specific language governing permissions and
016     * limitations under the License.
017     */
018    /*
019     * $Id: ElemTemplateElement.java 475981 2006-11-16 23:35:53Z minchau $
020     */
021    package org.apache.xalan.templates;
022    
023    import java.io.Serializable;
024    import java.util.ArrayList;
025    import java.util.Enumeration;
026    import java.util.List;
027    
028    import javax.xml.transform.SourceLocator;
029    import javax.xml.transform.TransformerException;
030    
031    import org.apache.xalan.res.XSLMessages;
032    import org.apache.xalan.res.XSLTErrorResources;
033    import org.apache.xalan.transformer.TransformerImpl;
034    import org.apache.xml.serializer.SerializationHandler;
035    import org.apache.xml.utils.PrefixResolver;
036    import org.apache.xml.utils.UnImplNode;
037    import org.apache.xpath.ExpressionNode;
038    import org.apache.xpath.WhitespaceStrippingElementMatcher;
039    
040    import org.w3c.dom.DOMException;
041    import org.w3c.dom.Document;
042    import org.w3c.dom.Node;
043    import org.w3c.dom.NodeList;
044    
045    import org.xml.sax.helpers.NamespaceSupport;
046    
047    /**
048     * An instance of this class represents an element inside
049     * an xsl:template class.  It has a single "execute" method
050     * which is expected to perform the given action on the
051     * result tree.
052     * This class acts like a Element node, and implements the
053     * Element interface, but is not a full implementation
054     * of that interface... it only implements enough for
055     * basic traversal of the tree.
056     *
057     * @see Stylesheet
058     * @xsl.usage advanced
059     */
060    public class ElemTemplateElement extends UnImplNode
061            implements PrefixResolver, Serializable, ExpressionNode, 
062                       WhitespaceStrippingElementMatcher, XSLTVisitable
063    {
064        static final long serialVersionUID = 4440018597841834447L;
065    
066      /**
067       * Construct a template element instance.
068       *
069       */
070      public ElemTemplateElement(){}
071    
072      /**
073       * Tell if this template is a compiled template.
074       *
075       * @return Boolean flag indicating whether this is a compiled template   
076       */
077      public boolean isCompiledTemplate()
078      {
079        return false;
080      }
081    
082      /**
083       * Get an integer representation of the element type.
084       *
085       * @return An integer representation of the element, defined in the
086       *     Constants class.
087       * @see org.apache.xalan.templates.Constants
088       */
089      public int getXSLToken()
090      {
091        return Constants.ELEMNAME_UNDEFINED;
092      }
093    
094      /**
095       * Return the node name.
096       *
097       * @return An invalid node name
098       */
099      public String getNodeName()
100      {
101        return "Unknown XSLT Element";
102      }
103      
104      /**
105       * For now, just return the result of getNodeName(), which 
106       * the local name.
107       *
108       * @return The result of getNodeName().
109       */
110      public String getLocalName()
111      {
112    
113        return getNodeName();
114      }
115    
116    
117      /**
118       * This function will be called on top-level elements
119       * only, just before the transform begins.
120       *
121       * @param transformer The XSLT TransformerFactory.
122       *
123       * @throws TransformerException
124       */
125      public void runtimeInit(TransformerImpl transformer) throws TransformerException{}
126    
127      /**
128       * Execute the element's primary function.  Subclasses of this
129       * function may recursivly execute down the element tree.
130       *
131       * @param transformer The XSLT TransformerFactory.
132       * 
133       * @throws TransformerException if any checked exception occurs.
134       */
135      public void execute(
136              TransformerImpl transformer)
137                throws TransformerException{}
138    
139      /**
140       * Get the owning "composed" stylesheet.  This looks up the
141       * inheritance chain until it calls getStylesheetComposed
142       * on a Stylesheet object, which will Get the owning
143       * aggregated stylesheet, or that stylesheet if it is aggregated.
144       *
145       * @return the owning "composed" stylesheet.
146       */
147      public StylesheetComposed getStylesheetComposed()
148      {
149        return m_parentNode.getStylesheetComposed();
150      }
151    
152      /**
153       * Get the owning stylesheet.  This looks up the
154       * inheritance chain until it calls getStylesheet
155       * on a Stylesheet object, which will return itself.
156       *
157       * @return the owning stylesheet
158       */
159      public Stylesheet getStylesheet()
160      {
161        return (null==m_parentNode) ? null : m_parentNode.getStylesheet();
162      }
163    
164      /**
165       * Get the owning root stylesheet.  This looks up the
166       * inheritance chain until it calls StylesheetRoot
167       * on a Stylesheet object, which will return a reference
168       * to the root stylesheet.
169       *
170       * @return the owning root stylesheet
171       */
172      public StylesheetRoot getStylesheetRoot()
173      {
174        return m_parentNode.getStylesheetRoot();
175      }
176    
177      /**
178       * This function is called during recomposition to
179       * control how this element is composed.
180       */
181      public void recompose(StylesheetRoot root) throws TransformerException
182      {
183      }
184    
185      /**
186       * This function is called after everything else has been
187       * recomposed, and allows the template to set remaining
188       * values that may be based on some other property that
189       * depends on recomposition.
190       */
191      public void compose(StylesheetRoot sroot) throws TransformerException
192      {
193        resolvePrefixTables();
194        ElemTemplateElement t = getFirstChildElem();
195        m_hasTextLitOnly = ((t != null) 
196                  && (t.getXSLToken() == Constants.ELEMNAME_TEXTLITERALRESULT) 
197                  && (t.getNextSiblingElem() == null));
198                  
199        StylesheetRoot.ComposeState cstate = sroot.getComposeState();
200        cstate.pushStackMark();
201      }
202      
203      /**
204       * This after the template's children have been composed.
205       */
206      public void endCompose(StylesheetRoot sroot) throws TransformerException
207      {
208        StylesheetRoot.ComposeState cstate = sroot.getComposeState();
209        cstate.popStackMark();
210      }
211    
212      /**
213       * Throw a template element runtime error.  (Note: should we throw a TransformerException instead?)
214       *
215       * @param msg key of the error that occured.
216       * @param args Arguments to be used in the message
217       */
218      public void error(String msg, Object[] args)
219      {
220    
221        String themsg = XSLMessages.createMessage(msg, args);
222    
223        throw new RuntimeException(XSLMessages.createMessage(
224                                        XSLTErrorResources.ER_ELEMTEMPLATEELEM_ERR,
225                                        new Object[]{ themsg }));
226      }
227      
228      /*
229       * Throw an error.
230       *
231       * @param msg Message key for the error
232       *
233       */
234      public void error(String msg)
235      {
236        error(msg, null);
237      }
238      
239    
240      // Implemented DOM Element methods.
241      /**
242       * Add a child to the child list.
243       * NOTE: This presumes the child did not previously have a parent.
244       * Making that assumption makes this a less expensive operation -- but
245       * requires that if you *do* want to reparent a node, you use removeChild()
246       * first to remove it from its previous context. Failing to do so will
247       * damage the tree.
248       *
249       * @param newChild Child to be added to child list
250       *
251       * @return Child just added to the child list
252       * @throws DOMException
253       */
254      public Node appendChild(Node newChild) throws DOMException
255      {
256    
257        if (null == newChild)
258        {
259          error(XSLTErrorResources.ER_NULL_CHILD, null);  //"Trying to add a null child!");
260        }
261    
262        ElemTemplateElement elem = (ElemTemplateElement) newChild;
263    
264        if (null == m_firstChild)
265        {
266          m_firstChild = elem;
267        }
268        else
269        {
270          ElemTemplateElement last = (ElemTemplateElement) getLastChild();
271    
272          last.m_nextSibling = elem;
273        }
274    
275        elem.m_parentNode = this;
276    
277        return newChild;
278      }
279    
280      /**
281       * Add a child to the child list.
282       * NOTE: This presumes the child did not previously have a parent.
283       * Making that assumption makes this a less expensive operation -- but
284       * requires that if you *do* want to reparent a node, you use removeChild()
285       * first to remove it from its previous context. Failing to do so will
286       * damage the tree.
287       *
288       * @param elem Child to be added to child list
289       *
290       * @return Child just added to the child list
291       */
292      public ElemTemplateElement appendChild(ElemTemplateElement elem)
293      {
294    
295        if (null == elem)
296        {
297          error(XSLTErrorResources.ER_NULL_CHILD, null);  //"Trying to add a null child!");
298        }
299    
300        if (null == m_firstChild)
301        {
302          m_firstChild = elem;
303        }
304        else
305        {
306          ElemTemplateElement last = getLastChildElem();
307    
308          last.m_nextSibling = elem;
309        }
310    
311        elem.setParentElem(this);
312    
313        return elem;
314      }
315    
316    
317      /**
318       * Tell if there are child nodes.
319       *
320       * @return True if there are child nodes
321       */
322      public boolean hasChildNodes()
323      {
324        return (null != m_firstChild);
325      }
326    
327      /**
328       * Get the type of the node.
329       *
330       * @return Constant for this node type
331       */
332      public short getNodeType()
333      {
334        return org.w3c.dom.Node.ELEMENT_NODE;
335      }
336    
337      /**
338       * Return the nodelist (same reference).
339       *
340       * @return The nodelist containing the child nodes (this)
341       */
342      public NodeList getChildNodes()
343      {
344        return this;
345      }
346    
347      /**
348       * Remove a child.
349       * ADDED 9/8/200 to support compilation.
350       * TODO: ***** Alternative is "removeMe() from my parent if any"
351       * ... which is less well checked, but more convenient in some cases.
352       * Given that we assume only experts are calling this class, it might
353       * be preferable. It's less DOMish, though.
354       * 
355       * @param childETE The child to remove. This operation is a no-op
356       * if oldChild is not a child of this node.
357       *
358       * @return the removed child, or null if the specified
359       * node was not a child of this element.
360       */
361      public ElemTemplateElement removeChild(ElemTemplateElement childETE)
362      {
363    
364        if (childETE == null || childETE.m_parentNode != this)
365          return null;
366    
367        // Pointers to the child
368        if (childETE == m_firstChild)
369          m_firstChild = childETE.m_nextSibling;
370        else
371        {
372          ElemTemplateElement prev = childETE.getPreviousSiblingElem();
373    
374          prev.m_nextSibling = childETE.m_nextSibling;
375        }
376    
377        // Pointers from the child
378        childETE.m_parentNode = null;
379        childETE.m_nextSibling = null;
380    
381        return childETE;
382      }
383    
384      /**
385       * Replace the old child with a new child.
386       *
387       * @param newChild New child to replace with
388       * @param oldChild Old child to be replaced
389       *
390       * @return The new child
391       *
392       * @throws DOMException
393       */
394      public Node replaceChild(Node newChild, Node oldChild) throws DOMException
395      {
396    
397        if (oldChild == null || oldChild.getParentNode() != this)
398          return null;
399    
400        ElemTemplateElement newChildElem = ((ElemTemplateElement) newChild);
401        ElemTemplateElement oldChildElem = ((ElemTemplateElement) oldChild);
402    
403        // Fix up previous sibling.
404        ElemTemplateElement prev =
405          (ElemTemplateElement) oldChildElem.getPreviousSibling();
406    
407        if (null != prev)
408          prev.m_nextSibling = newChildElem;
409    
410        // Fix up parent (this)
411        if (m_firstChild == oldChildElem)
412          m_firstChild = newChildElem;
413    
414        newChildElem.m_parentNode = this;
415        oldChildElem.m_parentNode = null;
416        newChildElem.m_nextSibling = oldChildElem.m_nextSibling;
417        oldChildElem.m_nextSibling = null;
418    
419        // newChildElem.m_stylesheet = oldChildElem.m_stylesheet;
420        // oldChildElem.m_stylesheet = null;
421        return newChildElem;
422      }
423      
424      /**
425       * Unimplemented. See org.w3c.dom.Node
426       *
427       * @param newChild New child node to insert
428       * @param refChild Insert in front of this child
429       *
430       * @return null
431       *
432       * @throws DOMException
433       */
434      public Node insertBefore(Node newChild, Node refChild) throws DOMException
435      {
436            if(null == refChild)
437            {
438                    appendChild(newChild);
439                    return newChild;
440            }
441            
442            if(newChild == refChild)
443            {
444                    // hmm...
445                    return newChild;
446            }
447    
448        Node node = m_firstChild; 
449        Node prev = null;  
450        boolean foundit = false;
451        
452        while (null != node)
453        {
454            // If the newChild is already in the tree, it is first removed.
455            if(newChild == node)
456            {
457                    if(null != prev)
458                            ((ElemTemplateElement)prev).m_nextSibling = 
459                                    (ElemTemplateElement)node.getNextSibling();
460                    else
461                            m_firstChild = (ElemTemplateElement)node.getNextSibling();
462                    node = node.getNextSibling();
463                    continue; // prev remains the same.
464            }
465            if(refChild == node)
466            {
467                    if(null != prev)
468                    {
469                            ((ElemTemplateElement)prev).m_nextSibling = (ElemTemplateElement)newChild;
470                    }
471                    else
472                    {
473                            m_firstChild = (ElemTemplateElement)newChild;
474                    }
475                    ((ElemTemplateElement)newChild).m_nextSibling = (ElemTemplateElement)refChild;
476                    ((ElemTemplateElement)newChild).setParentElem(this);
477                    prev = newChild;
478                    node = node.getNextSibling();
479                    foundit = true;
480                    continue;
481            }
482            prev = node;
483            node = node.getNextSibling();
484        }
485        
486        if(!foundit)
487            throw new DOMException(DOMException.NOT_FOUND_ERR, 
488                    "refChild was not found in insertBefore method!");
489        else
490            return newChild;
491      }
492    
493    
494      /**
495       * Replace the old child with a new child.
496       *
497       * @param newChildElem New child to replace with
498       * @param oldChildElem Old child to be replaced
499       *
500       * @return The new child
501       *
502       * @throws DOMException
503       */
504      public ElemTemplateElement replaceChild(ElemTemplateElement newChildElem, 
505                                              ElemTemplateElement oldChildElem)
506      {
507    
508        if (oldChildElem == null || oldChildElem.getParentElem() != this)
509          return null;
510    
511        // Fix up previous sibling.
512        ElemTemplateElement prev =
513          oldChildElem.getPreviousSiblingElem();
514    
515        if (null != prev)
516          prev.m_nextSibling = newChildElem;
517    
518        // Fix up parent (this)
519        if (m_firstChild == oldChildElem)
520          m_firstChild = newChildElem;
521    
522        newChildElem.m_parentNode = this;
523        oldChildElem.m_parentNode = null;
524        newChildElem.m_nextSibling = oldChildElem.m_nextSibling;
525        oldChildElem.m_nextSibling = null;
526    
527        // newChildElem.m_stylesheet = oldChildElem.m_stylesheet;
528        // oldChildElem.m_stylesheet = null;
529        return newChildElem;
530      }
531    
532      /**
533       * NodeList method: Count the immediate children of this node
534       *
535       * @return The count of children of this node
536       */
537      public int getLength()
538      {
539    
540        // It is assumed that the getChildNodes call synchronized
541        // the children. Therefore, we can access the first child
542        // reference directly.
543        int count = 0;
544    
545        for (ElemTemplateElement node = m_firstChild; node != null;
546                node = node.m_nextSibling)
547        {
548          count++;
549        }
550    
551        return count;
552      }  // getLength():int
553    
554      /**
555       * NodeList method: Return the Nth immediate child of this node, or
556       * null if the index is out of bounds.
557       *
558       * @param index Index of child to find
559       * @return org.w3c.dom.Node: the child node at given index
560       */
561      public Node item(int index)
562      {
563    
564        // It is assumed that the getChildNodes call synchronized
565        // the children. Therefore, we can access the first child
566        // reference directly.
567        ElemTemplateElement node = m_firstChild;
568    
569        for (int i = 0; i < index && node != null; i++)
570        {
571          node = node.m_nextSibling;
572        }
573    
574        return node;
575      }  // item(int):Node
576    
577      /**
578       * Get the stylesheet owner.
579       *
580       * @return The stylesheet owner
581       */
582      public Document getOwnerDocument()
583      {
584        return getStylesheet();
585      }
586      
587      /**
588       * Get the owning xsl:template element.
589       *
590       * @return The owning xsl:template element, this element if it is a xsl:template, or null if not found.
591       */
592      public ElemTemplate getOwnerXSLTemplate()
593      {
594            ElemTemplateElement el = this;
595            int type = el.getXSLToken();
596            while((null != el) && (type != Constants.ELEMNAME_TEMPLATE))
597            {
598            el = el.getParentElem();
599            if(null != el)
600                            type = el.getXSLToken();
601            }
602            return (ElemTemplate)el;
603      }
604    
605    
606      /**
607       * Return the element name.
608       *
609       * @return The element name
610       */
611      public String getTagName()
612      {
613        return getNodeName();
614      }
615      
616      /**
617       * Tell if this element only has one text child, for optimization purposes.
618       * @return true of this element only has one text literal child.
619       */
620      public boolean hasTextLitOnly()
621      {
622        return m_hasTextLitOnly;
623      }
624    
625      /**
626       * Return the base identifier.
627       *
628       * @return The base identifier 
629       */
630      public String getBaseIdentifier()
631      {
632    
633        // Should this always be absolute?
634        return this.getSystemId();
635      }
636    
637      /** line number where the current document event ends.
638       *  @serial         */
639      private int m_lineNumber;
640    
641      /** line number where the current document event ends.
642       *  @serial         */
643      private int m_endLineNumber;
644    
645      /**
646       * Return the line number where the current document event ends.
647       * Note that this is the line position of the first character
648       * after the text associated with the document event.
649       * @return The line number, or -1 if none is available.
650       * @see #getColumnNumber
651       */
652      public int getEndLineNumber()
653      {
654            return m_endLineNumber;
655      }
656    
657      /**
658       * Return the line number where the current document event ends.
659       * Note that this is the line position of the first character
660       * after the text associated with the document event.
661       * @return The line number, or -1 if none is available.
662       * @see #getColumnNumber
663       */
664      public int getLineNumber()
665      {
666        return m_lineNumber;
667      }
668    
669      /** the column number where the current document event ends.
670       *  @serial        */
671      private int m_columnNumber;
672    
673      /** the column number where the current document event ends.
674       *  @serial        */
675      private int m_endColumnNumber;
676    
677      /**
678       * Return the column number where the current document event ends.
679       * Note that this is the column number of the first
680       * character after the text associated with the document
681       * event.  The first column in a line is position 1.
682       * @return The column number, or -1 if none is available.
683       * @see #getLineNumber
684       */
685      public int getEndColumnNumber()
686      {
687            return m_endColumnNumber;
688      }
689    
690      /**
691       * Return the column number where the current document event ends.
692       * Note that this is the column number of the first
693       * character after the text associated with the document
694       * event.  The first column in a line is position 1.
695       * @return The column number, or -1 if none is available.
696       * @see #getLineNumber
697       */
698      public int getColumnNumber()
699      {
700        return m_columnNumber;
701      }
702    
703      /**
704       * Return the public identifier for the current document event.
705       * <p>This will be the public identifier
706       * @return A string containing the public identifier, or
707       *         null if none is available.
708       * @see #getSystemId
709       */
710      public String getPublicId()
711      {
712        return (null != m_parentNode) ? m_parentNode.getPublicId() : null;
713      }
714    
715      /**
716       * Return the system identifier for the current document event.
717       *
718       * <p>If the system identifier is a URL, the parser must resolve it
719       * fully before passing it to the application.</p>
720       *
721       * @return A string containing the system identifier, or null
722       *         if none is available.
723       * @see #getPublicId
724       */
725      public String getSystemId()
726      {
727        Stylesheet sheet=getStylesheet();
728        return (sheet==null) ? null : sheet.getHref();
729      }
730    
731      /**
732       * Set the location information for this element.
733       *
734       * @param locator Source Locator with location information for this element
735       */
736      public void setLocaterInfo(SourceLocator locator)
737      {
738        m_lineNumber = locator.getLineNumber();
739        m_columnNumber = locator.getColumnNumber();
740      }
741      
742      /**
743       * Set the end location information for this element.
744       *
745       * @param locator Source Locator with location information for this element
746       */
747      public void setEndLocaterInfo(SourceLocator locator)
748      {
749            m_endLineNumber = locator.getLineNumber();
750            m_endColumnNumber = locator.getColumnNumber();
751      } 
752    
753      /**
754       * Tell if this element has the default space handling
755       * turned off or on according to the xml:space attribute.
756       * @serial
757       */
758      private boolean m_defaultSpace = true;
759    
760      /**
761       * Tell if this element only has one text child, for optimization purposes.
762       * @serial
763       */
764      private boolean m_hasTextLitOnly = false;
765    
766      /**
767       * Tell if this element only has one text child, for optimization purposes.
768       * @serial
769       */
770      protected boolean m_hasVariableDecl = false;
771      
772      public boolean hasVariableDecl()
773      {
774        return m_hasVariableDecl;
775      }
776    
777      /**
778       * Set the "xml:space" attribute.
779       * A text node is preserved if an ancestor element of the text node
780       * has an xml:space attribute with a value of preserve, and
781       * no closer ancestor element has xml:space with a value of default.
782       * @see <a href="http://www.w3.org/TR/xslt#strip">strip in XSLT Specification</a>
783       * @see <a href="http://www.w3.org/TR/xslt#section-Creating-Text">section-Creating-Text in XSLT Specification</a>
784       *
785       * @param v  Enumerated value, either Constants.ATTRVAL_PRESERVE 
786       * or Constants.ATTRVAL_STRIP.
787       */
788      public void setXmlSpace(int v)
789      {
790        m_defaultSpace = ((Constants.ATTRVAL_STRIP == v) ? true : false);
791      }
792    
793      /**
794       * Get the "xml:space" attribute.
795       * A text node is preserved if an ancestor element of the text node
796       * has an xml:space attribute with a value of preserve, and
797       * no closer ancestor element has xml:space with a value of default.
798       * @see <a href="http://www.w3.org/TR/xslt#strip">strip in XSLT Specification</a>
799       * @see <a href="http://www.w3.org/TR/xslt#section-Creating-Text">section-Creating-Text in XSLT Specification</a>
800       *
801       * @return The value of the xml:space attribute
802       */
803      public boolean getXmlSpace()
804      {
805        return m_defaultSpace;
806      }
807    
808      /**
809       * The list of namespace declarations for this element only.
810       * @serial
811       */
812      private List m_declaredPrefixes;
813    
814      /**
815       * Return a table that contains all prefixes available
816       * within this element context.
817       *
818       * @return Vector containing the prefixes available within this
819       * element context 
820       */
821      public List getDeclaredPrefixes()
822      {
823        return m_declaredPrefixes;
824      }
825    
826      /**
827       * From the SAX2 helper class, set the namespace table for
828       * this element.  Take care to call resolveInheritedNamespaceDecls.
829       * after all namespace declarations have been added.
830       *
831       * @param nsSupport non-null reference to NamespaceSupport from 
832       * the ContentHandler.
833       *
834       * @throws TransformerException
835       */
836      public void setPrefixes(NamespaceSupport nsSupport) throws TransformerException
837      {
838        setPrefixes(nsSupport, false);
839      }
840    
841      /**
842       * Copy the namespace declarations from the NamespaceSupport object.  
843       * Take care to call resolveInheritedNamespaceDecls.
844       * after all namespace declarations have been added.
845       *
846       * @param nsSupport non-null reference to NamespaceSupport from 
847       * the ContentHandler.
848       * @param excludeXSLDecl true if XSLT namespaces should be ignored.
849       *
850       * @throws TransformerException
851       */
852      public void setPrefixes(NamespaceSupport nsSupport, boolean excludeXSLDecl)
853              throws TransformerException
854      {
855    
856        Enumeration decls = nsSupport.getDeclaredPrefixes();
857    
858        while (decls.hasMoreElements())
859        {
860          String prefix = (String) decls.nextElement();
861    
862          if (null == m_declaredPrefixes)
863            m_declaredPrefixes = new ArrayList();
864    
865          String uri = nsSupport.getURI(prefix);
866    
867          if (excludeXSLDecl && uri.equals(Constants.S_XSLNAMESPACEURL))
868            continue;
869    
870          // System.out.println("setPrefixes - "+prefix+", "+uri);
871          XMLNSDecl decl = new XMLNSDecl(prefix, uri, false);
872    
873          m_declaredPrefixes.add(decl);
874        }
875      }
876    
877      /**
878       * Fullfill the PrefixResolver interface.  Calling this for this class 
879       * will throw an error.
880       *
881       * @param prefix The prefix to look up, which may be an empty string ("") 
882       *               for the default Namespace.
883       * @param context The node context from which to look up the URI.
884       *
885       * @return null if the error listener does not choose to throw an exception.
886       */
887      public String getNamespaceForPrefix(String prefix, org.w3c.dom.Node context)
888      {
889        this.error(XSLTErrorResources.ER_CANT_RESOLVE_NSPREFIX, null);
890    
891        return null;
892      }
893    
894      /**
895       * Given a namespace, get the corrisponding prefix.
896       * 9/15/00: This had been iteratively examining the m_declaredPrefixes
897       * field for this node and its parents. That makes life difficult for
898       * the compilation experiment, which doesn't have a static vector of
899       * local declarations. Replaced a recursive solution, which permits
900       * easier subclassing/overriding.
901       *
902       * @param prefix non-null reference to prefix string, which should map 
903       *               to a namespace URL.
904       *
905       * @return The namespace URL that the prefix maps to, or null if no 
906       *         mapping can be found.
907       */
908      public String getNamespaceForPrefix(String prefix)
909      {
910    //    if (null != prefix && prefix.equals("xmlns"))
911    //    {
912    //      return Constants.S_XMLNAMESPACEURI;
913    //    }
914    
915        List nsDecls = m_declaredPrefixes;
916    
917        if (null != nsDecls)
918        {
919          int n = nsDecls.size();
920          if(prefix.equals(Constants.ATTRVAL_DEFAULT_PREFIX))
921          {
922            prefix = "";
923          }
924    
925          for (int i = 0; i < n; i++)
926          {
927            XMLNSDecl decl = (XMLNSDecl) nsDecls.get(i);
928    
929            if (prefix.equals(decl.getPrefix()))
930              return decl.getURI();
931          }
932        }
933    
934        // Not found; ask our ancestors
935        if (null != m_parentNode)
936          return m_parentNode.getNamespaceForPrefix(prefix);
937    
938        // JJK: No ancestors; try implicit
939        // %REVIEW% Are there literals somewhere that we should use instead?
940        // %REVIEW% Is this really the best place to patch?
941        if("xml".equals(prefix))
942          return "http://www.w3.org/XML/1998/namespace";
943    
944        // No parent, so no definition
945        return null;
946      }
947    
948      /**
949       * The table of {@link XMLNSDecl}s for this element
950       * and all parent elements, screened for excluded prefixes.
951       * @serial
952       */
953      private List m_prefixTable;
954    
955      /**
956       * Return a table that contains all prefixes available
957       * within this element context.
958       *
959       * @return reference to vector of {@link XMLNSDecl}s, which may be null.
960       */
961      List getPrefixTable()
962      {
963        return m_prefixTable;
964      }
965      
966      void setPrefixTable(List list) {
967          m_prefixTable = list;
968      }
969      
970      /**
971       * Get whether or not the passed URL is contained flagged by
972       * the "extension-element-prefixes" property.  This method is overridden 
973       * by {@link ElemLiteralResult#containsExcludeResultPrefix}.
974       * @see <a href="http://www.w3.org/TR/xslt#extension-element">extension-element in XSLT Specification</a>
975       *
976       * @param prefix non-null reference to prefix that might be excluded.
977       *
978       * @return true if the prefix should normally be excluded.
979       */
980      public boolean containsExcludeResultPrefix(String prefix, String uri)
981      {
982        ElemTemplateElement parent = this.getParentElem();
983        if(null != parent)
984          return parent.containsExcludeResultPrefix(prefix, uri);
985          
986        return false;
987      }
988    
989      /**
990       * Tell if the result namespace decl should be excluded.  Should be called before
991       * namespace aliasing (I think).
992       *
993       * @param prefix non-null reference to prefix.
994       * @param uri reference to namespace that prefix maps to, which is protected 
995       *            for null, but should really never be passed as null.
996       *
997       * @return true if the given namespace should be excluded.
998       *
999       * @throws TransformerException
1000       */
1001      private boolean excludeResultNSDecl(String prefix, String uri)
1002              throws TransformerException
1003      {
1004    
1005        if (uri != null)
1006        {
1007          if (uri.equals(Constants.S_XSLNAMESPACEURL)
1008                  || getStylesheet().containsExtensionElementURI(uri))
1009            return true;
1010    
1011          if (containsExcludeResultPrefix(prefix, uri))
1012            return true;
1013        }
1014    
1015        return false;
1016      }
1017      
1018      /**
1019       * Combine the parent's namespaces with this namespace
1020       * for fast processing, taking care to reference the
1021       * parent's namespace if this namespace adds nothing new.
1022       * (Recursive method, walking the elements depth-first,
1023       * processing parents before children).
1024       * Note that this method builds m_prefixTable with aliased 
1025       * namespaces, *not* the original namespaces.
1026       *
1027       * @throws TransformerException
1028       */
1029      public void resolvePrefixTables() throws TransformerException
1030      {
1031        // Always start with a fresh prefix table!
1032        setPrefixTable(null);
1033    
1034        // If we have declared declarations, then we look for 
1035        // a parent that has namespace decls, and add them 
1036        // to this element's decls.  Otherwise we just point 
1037        // to the parent that has decls.
1038        if (null != this.m_declaredPrefixes)
1039        {
1040          StylesheetRoot stylesheet = this.getStylesheetRoot();
1041          
1042          // Add this element's declared prefixes to the 
1043          // prefix table.
1044          int n = m_declaredPrefixes.size();
1045    
1046          for (int i = 0; i < n; i++)
1047          {
1048            XMLNSDecl decl = (XMLNSDecl) m_declaredPrefixes.get(i);
1049            String prefix = decl.getPrefix();
1050            String uri = decl.getURI();
1051            if(null == uri)
1052              uri = "";
1053            boolean shouldExclude = excludeResultNSDecl(prefix, uri);
1054    
1055            // Create a new prefix table if one has not already been created.
1056            if (null == m_prefixTable)
1057                setPrefixTable(new ArrayList());
1058    
1059            NamespaceAlias nsAlias = stylesheet.getNamespaceAliasComposed(uri);
1060            if(null != nsAlias)
1061            {
1062              // Should I leave the non-aliased element in the table as 
1063              // an excluded element?
1064              
1065              // The exclusion should apply to the non-aliased prefix, so 
1066              // we don't calculate it here.  -sb
1067              // Use stylesheet prefix, as per xsl WG
1068              decl = new XMLNSDecl(nsAlias.getStylesheetPrefix(), 
1069                                  nsAlias.getResultNamespace(), shouldExclude);
1070            }
1071            else
1072              decl = new XMLNSDecl(prefix, uri, shouldExclude);
1073    
1074            m_prefixTable.add(decl);
1075            
1076          }
1077        }
1078    
1079        ElemTemplateElement parent = this.getParentNodeElem();
1080    
1081        if (null != parent)
1082        {
1083    
1084          // The prefix table of the parent should never be null!
1085          List prefixes = parent.m_prefixTable;
1086    
1087          if (null == m_prefixTable && !needToCheckExclude())
1088          {
1089    
1090            // Nothing to combine, so just use parent's table!
1091            setPrefixTable(parent.m_prefixTable);
1092          }
1093          else
1094          {
1095    
1096            // Add the prefixes from the parent's prefix table.
1097            int n = prefixes.size();
1098            
1099            for (int i = 0; i < n; i++)
1100            {
1101              XMLNSDecl decl = (XMLNSDecl) prefixes.get(i);
1102              boolean shouldExclude = excludeResultNSDecl(decl.getPrefix(),
1103                                                          decl.getURI());
1104    
1105              if (shouldExclude != decl.getIsExcluded())
1106              {
1107                decl = new XMLNSDecl(decl.getPrefix(), decl.getURI(),
1108                                     shouldExclude);
1109              }
1110              
1111              //m_prefixTable.addElement(decl);
1112              addOrReplaceDecls(decl);
1113            }
1114          }
1115        }
1116        else if (null == m_prefixTable)
1117        {
1118    
1119          // Must be stylesheet element without any result prefixes!
1120          setPrefixTable(new ArrayList());
1121        }
1122      }
1123      
1124      /**
1125       * Add or replace this namespace declaration in list
1126       * of namespaces in scope for this element.
1127       *
1128       * @param newDecl namespace declaration to add to list
1129       */
1130      void addOrReplaceDecls(XMLNSDecl newDecl)
1131      {
1132          int n = m_prefixTable.size();
1133    
1134            for (int i = n - 1; i >= 0; i--)
1135            {
1136              XMLNSDecl decl = (XMLNSDecl) m_prefixTable.get(i);
1137    
1138              if (decl.getPrefix().equals(newDecl.getPrefix()))
1139              {
1140                return;
1141              }
1142            }
1143          m_prefixTable.add(newDecl);    
1144        
1145      }
1146      
1147      /**
1148       * Return whether we need to check namespace prefixes 
1149       * against and exclude result prefixes list.
1150       */
1151      boolean needToCheckExclude()
1152      {
1153        return false;    
1154      } 
1155    
1156      /**
1157       * Send startPrefixMapping events to the result tree handler
1158       * for all declared prefix mappings in the stylesheet.
1159       *
1160       * @param transformer non-null reference to the the current transform-time state.
1161       *
1162       * @throws TransformerException
1163       */
1164      void executeNSDecls(TransformerImpl transformer) throws TransformerException
1165      {
1166           executeNSDecls(transformer, null);
1167      }
1168    
1169      /**
1170       * Send startPrefixMapping events to the result tree handler
1171       * for all declared prefix mappings in the stylesheet.
1172       *
1173       * @param transformer non-null reference to the the current transform-time state.
1174       * @param ignorePrefix string prefix to not startPrefixMapping
1175       *
1176       * @throws TransformerException
1177       */
1178      void executeNSDecls(TransformerImpl transformer, String ignorePrefix) throws TransformerException
1179      {  
1180        try
1181        {
1182          if (null != m_prefixTable)
1183          {
1184            SerializationHandler rhandler = transformer.getResultTreeHandler();
1185            int n = m_prefixTable.size();
1186    
1187            for (int i = n - 1; i >= 0; i--)
1188            {
1189              XMLNSDecl decl = (XMLNSDecl) m_prefixTable.get(i);
1190    
1191              if (!decl.getIsExcluded() && !(null != ignorePrefix && decl.getPrefix().equals(ignorePrefix)))
1192              {
1193                rhandler.startPrefixMapping(decl.getPrefix(), decl.getURI(), true);
1194              }
1195            }
1196          }
1197        }
1198        catch(org.xml.sax.SAXException se)
1199        {
1200          throw new TransformerException(se);
1201        }
1202      }
1203    
1204      /**
1205       * Send endPrefixMapping events to the result tree handler
1206       * for all declared prefix mappings in the stylesheet.
1207       *
1208       * @param transformer non-null reference to the the current transform-time state.
1209       *
1210       * @throws TransformerException
1211       */
1212      void unexecuteNSDecls(TransformerImpl transformer) throws TransformerException
1213      {
1214           unexecuteNSDecls(transformer, null);
1215      }
1216    
1217      /**
1218       * Send endPrefixMapping events to the result tree handler
1219       * for all declared prefix mappings in the stylesheet.
1220       *
1221       * @param transformer non-null reference to the the current transform-time state.
1222       * @param ignorePrefix string prefix to not endPrefixMapping
1223       * 
1224       * @throws TransformerException
1225       */
1226      void unexecuteNSDecls(TransformerImpl transformer, String ignorePrefix) throws TransformerException
1227      {
1228     
1229        try
1230        {
1231          if (null != m_prefixTable)
1232          {
1233            SerializationHandler rhandler = transformer.getResultTreeHandler();
1234            int n = m_prefixTable.size();
1235    
1236            for (int i = 0; i < n; i++)
1237            {
1238              XMLNSDecl decl = (XMLNSDecl) m_prefixTable.get(i);
1239    
1240              if (!decl.getIsExcluded() && !(null != ignorePrefix && decl.getPrefix().equals(ignorePrefix)))
1241              {
1242                rhandler.endPrefixMapping(decl.getPrefix());
1243              }
1244            }
1245          }
1246        }
1247        catch(org.xml.sax.SAXException se)
1248        {
1249          throw new TransformerException(se);
1250        }
1251      }
1252      
1253      /** The *relative* document order number of this element.
1254       *  @serial */
1255      protected int m_docOrderNumber = -1;
1256      
1257      /**
1258       * Set the UID (document order index).
1259       *
1260       * @param i Index of this child.
1261       */
1262      public void setUid(int i)
1263      {
1264        m_docOrderNumber = i;
1265      }
1266    
1267      /**
1268       * Get the UID (document order index).
1269       *
1270       * @return Index of this child
1271       */
1272      public int getUid()
1273      {
1274        return m_docOrderNumber;
1275      }
1276    
1277    
1278      /**
1279       * Parent node.
1280       * @serial
1281       */
1282      protected ElemTemplateElement m_parentNode;
1283    
1284      /**
1285       * Get the parent as a Node.
1286       *
1287       * @return This node's parent node
1288       */
1289      public Node getParentNode()
1290      {
1291        return m_parentNode;
1292      }
1293    
1294      /**
1295       * Get the parent as an ElemTemplateElement.
1296       *
1297       * @return This node's parent as an ElemTemplateElement
1298       */
1299      public ElemTemplateElement getParentElem()
1300      {
1301        return m_parentNode;
1302      }
1303    
1304      /**
1305       * Set the parent as an ElemTemplateElement.
1306       *
1307       * @param p This node's parent as an ElemTemplateElement
1308       */
1309      public void setParentElem(ElemTemplateElement p)
1310      {
1311        m_parentNode = p;
1312      }
1313    
1314      /**
1315       * Next sibling.
1316       * @serial
1317       */
1318      ElemTemplateElement m_nextSibling;
1319    
1320      /**
1321       * Get the next sibling (as a Node) or return null.
1322       *
1323       * @return this node's next sibling or null
1324       */
1325      public Node getNextSibling()
1326      {
1327        return m_nextSibling;
1328      }
1329    
1330      /**
1331       * Get the previous sibling (as a Node) or return null.
1332       * Note that this may be expensive if the parent has many kids;
1333       * we accept that price in exchange for avoiding the prev pointer
1334       * TODO: If we were sure parents and sibs are always ElemTemplateElements,
1335       * we could hit the fields directly rather than thru accessors.
1336       *
1337       * @return This node's previous sibling or null
1338       */
1339      public Node getPreviousSibling()
1340      {
1341    
1342        Node walker = getParentNode(), prev = null;
1343    
1344        if (walker != null)
1345          for (walker = walker.getFirstChild(); walker != null;
1346                  prev = walker, walker = walker.getNextSibling())
1347          {
1348            if (walker == this)
1349              return prev;
1350          }
1351    
1352        return null;
1353      }
1354    
1355      /**
1356       * Get the previous sibling (as a Node) or return null.
1357       * Note that this may be expensive if the parent has many kids;
1358       * we accept that price in exchange for avoiding the prev pointer
1359       * TODO: If we were sure parents and sibs are always ElemTemplateElements,
1360       * we could hit the fields directly rather than thru accessors.
1361       *
1362       * @return This node's previous sibling or null
1363       */
1364      public ElemTemplateElement getPreviousSiblingElem()
1365      {
1366    
1367        ElemTemplateElement walker = getParentNodeElem();
1368        ElemTemplateElement prev = null;
1369    
1370        if (walker != null)
1371          for (walker = walker.getFirstChildElem(); walker != null;
1372                  prev = walker, walker = walker.getNextSiblingElem())
1373          {
1374            if (walker == this)
1375              return prev;
1376          }
1377    
1378        return null;
1379      }
1380    
1381    
1382      /**
1383       * Get the next sibling (as a ElemTemplateElement) or return null.
1384       *
1385       * @return This node's next sibling (as a ElemTemplateElement) or null 
1386       */
1387      public ElemTemplateElement getNextSiblingElem()
1388      {
1389        return m_nextSibling;
1390      }
1391      
1392      /**
1393       * Get the parent element.
1394       *
1395       * @return This node's next parent (as a ElemTemplateElement) or null 
1396       */
1397      public ElemTemplateElement getParentNodeElem()
1398      {
1399        return m_parentNode;
1400      }
1401    
1402    
1403      /**
1404       * First child.
1405       * @serial
1406       */
1407      ElemTemplateElement m_firstChild;
1408    
1409      /**
1410       * Get the first child as a Node.
1411       *
1412       * @return This node's first child or null
1413       */
1414      public Node getFirstChild()
1415      {
1416        return m_firstChild;
1417      }
1418    
1419      /**
1420       * Get the first child as a ElemTemplateElement.
1421       *
1422       * @return This node's first child (as a ElemTemplateElement) or null
1423       */
1424      public ElemTemplateElement getFirstChildElem()
1425      {
1426        return m_firstChild;
1427      }
1428    
1429      /**
1430       * Get the last child.
1431       *
1432       * @return This node's last child
1433       */
1434      public Node getLastChild()
1435      {
1436    
1437        ElemTemplateElement lastChild = null;
1438    
1439        for (ElemTemplateElement node = m_firstChild; node != null;
1440                node = node.m_nextSibling)
1441        {
1442          lastChild = node;
1443        }
1444    
1445        return lastChild;
1446      }
1447    
1448      /**
1449       * Get the last child.
1450       *
1451       * @return This node's last child
1452       */
1453      public ElemTemplateElement getLastChildElem()
1454      {
1455    
1456        ElemTemplateElement lastChild = null;
1457    
1458        for (ElemTemplateElement node = m_firstChild; node != null;
1459                node = node.m_nextSibling)
1460        {
1461          lastChild = node;
1462        }
1463    
1464        return lastChild;
1465      }
1466    
1467    
1468      /** DOM backpointer that this element originated from.          */
1469      transient private org.w3c.dom.Node m_DOMBackPointer;
1470    
1471      /**
1472       * If this stylesheet was created from a DOM, get the
1473       * DOM backpointer that this element originated from.
1474       * For tooling use.
1475       *
1476       * @return DOM backpointer that this element originated from or null.
1477       */
1478      public org.w3c.dom.Node getDOMBackPointer()
1479      {
1480        return m_DOMBackPointer;
1481      }
1482    
1483      /**
1484       * If this stylesheet was created from a DOM, set the
1485       * DOM backpointer that this element originated from.
1486       * For tooling use.
1487       *
1488       * @param n DOM backpointer that this element originated from.
1489       */
1490      public void setDOMBackPointer(org.w3c.dom.Node n)
1491      {
1492        m_DOMBackPointer = n;
1493      }
1494    
1495      /**
1496       * Compares this object with the specified object for precedence order.
1497       * The order is determined by the getImportCountComposed() of the containing
1498       * composed stylesheet and the getUid() of this element.
1499       * Returns a negative integer, zero, or a positive integer as this
1500       * object is less than, equal to, or greater than the specified object.
1501       * 
1502       * @param o The object to be compared to this object
1503       * @return  a negative integer, zero, or a positive integer as this object is
1504       *          less than, equal to, or greater than the specified object.
1505       * @throws ClassCastException if the specified object's
1506       *         type prevents it from being compared to this Object.
1507       */
1508      public int compareTo(Object o) throws ClassCastException {
1509        
1510        ElemTemplateElement ro = (ElemTemplateElement) o;
1511        int roPrecedence = ro.getStylesheetComposed().getImportCountComposed();
1512        int myPrecedence = this.getStylesheetComposed().getImportCountComposed();
1513    
1514        if (myPrecedence < roPrecedence)
1515          return -1;
1516        else if (myPrecedence > roPrecedence)
1517          return 1;
1518        else
1519          return this.getUid() - ro.getUid();
1520      }
1521      
1522      /**
1523       * Get information about whether or not an element should strip whitespace.
1524       * @see <a href="http://www.w3.org/TR/xslt#strip">strip in XSLT Specification</a>
1525       *
1526       * @param support The XPath runtime state.
1527       * @param targetElement Element to check
1528       *
1529       * @return true if the whitespace should be stripped.
1530       *
1531       * @throws TransformerException
1532       */
1533      public boolean shouldStripWhiteSpace(
1534              org.apache.xpath.XPathContext support, 
1535              org.w3c.dom.Element targetElement) throws TransformerException
1536      {
1537        StylesheetRoot sroot = this.getStylesheetRoot();
1538        return (null != sroot) ? sroot.shouldStripWhiteSpace(support, targetElement) :false;
1539      }
1540      
1541      /**
1542       * Get information about whether or not whitespace can be stripped.
1543       * @see <a href="http://www.w3.org/TR/xslt#strip">strip in XSLT Specification</a>
1544       *
1545       * @return true if the whitespace can be stripped.
1546       */
1547      public boolean canStripWhiteSpace()
1548      {
1549        StylesheetRoot sroot = this.getStylesheetRoot();
1550        return (null != sroot) ? sroot.canStripWhiteSpace() : false;
1551      }
1552      
1553      /**
1554       * Tell if this element can accept variable declarations.
1555       * @return true if the element can accept and process variable declarations.
1556       */
1557      public boolean canAcceptVariables()
1558      {
1559            return true;
1560      }
1561      
1562      //=============== ExpressionNode methods ================
1563      
1564      /** 
1565       * Set the parent of this node.
1566       * @param n Must be a ElemTemplateElement.
1567       */
1568      public void exprSetParent(ExpressionNode n)
1569      {
1570            // This obviously requires that only a ElemTemplateElement can 
1571            // parent a node of this type.
1572            setParentElem((ElemTemplateElement)n);
1573      }
1574      
1575      /**
1576       * Get the ExpressionNode parent of this node.
1577       */
1578      public ExpressionNode exprGetParent()
1579      {
1580            return getParentElem();
1581      }
1582    
1583      /** 
1584       * This method tells the node to add its argument to the node's
1585       * list of children. 
1586       * @param n Must be a ElemTemplateElement. 
1587       */
1588      public void exprAddChild(ExpressionNode n, int i)
1589      {
1590            appendChild((ElemTemplateElement)n);
1591      }
1592    
1593      /** This method returns a child node.  The children are numbered
1594         from zero, left to right. */
1595      public ExpressionNode exprGetChild(int i)
1596      {
1597            return (ExpressionNode)item(i);
1598      }
1599    
1600      /** Return the number of children the node has. */
1601      public int exprGetNumChildren()
1602      {
1603            return getLength();
1604      }
1605      
1606      /**
1607       * Accept a visitor and call the appropriate method 
1608       * for this class.
1609       * 
1610       * @param visitor The visitor whose appropriate method will be called.
1611       * @return true if the children of the object should be visited.
1612       */
1613      protected boolean accept(XSLTVisitor visitor)
1614      {
1615            return visitor.visitInstruction(this);
1616      }
1617    
1618      /**
1619       * @see XSLTVisitable#callVisitors(XSLTVisitor)
1620       */
1621      public void callVisitors(XSLTVisitor visitor)
1622      {
1623            if(accept(visitor))
1624            {
1625                    callChildVisitors(visitor);
1626            }
1627      }
1628    
1629      /**
1630       * Call the children visitors.
1631       * @param visitor The visitor whose appropriate method will be called.
1632       */
1633      protected void callChildVisitors(XSLTVisitor visitor, boolean callAttributes)
1634      {
1635        for (ElemTemplateElement node = m_firstChild;
1636          node != null;
1637          node = node.m_nextSibling)
1638          {
1639          node.callVisitors(visitor);
1640        }
1641      }
1642      
1643      /**
1644       * Call the children visitors.
1645       * @param visitor The visitor whose appropriate method will be called.
1646       */
1647      protected void callChildVisitors(XSLTVisitor visitor)
1648      {
1649            callChildVisitors(visitor, true);
1650      }
1651    
1652    
1653            /**
1654             * @see PrefixResolver#handlesNullPrefixes()
1655             */
1656            public boolean handlesNullPrefixes() {
1657                    return false;
1658            }
1659    
1660    }