Java Code Examples for org.apache.xpath.XPathContext#getDTM()

/**
 * Execute an expression in the XPath runtime context, and return the 
 * result of the expression.
 *
 *
 * @param xctxt The XPath runtime context.
 *
 * @return The result of the expression in the form of a <code>XObject</code>.
 *
 * @throws javax.xml.transform.TransformerException if a runtime exception 
 *         occurs.
 */
public void executeCharsToContentHandler(XPathContext xctxt, 
                                            ContentHandler handler)
  throws javax.xml.transform.TransformerException,
         org.xml.sax.SAXException
{
  if(Arg0IsNodesetExpr())
  {
    int node = getArg0AsNode(xctxt);
    if(DTM.NULL != node)
    {
      DTM dtm = xctxt.getDTM(node);
      dtm.dispatchCharactersEvents(node, handler, true);
    }
  }
  else
  {
    XObject obj = execute(xctxt);
    obj.dispatchCharactersEvents(handler);
  }
}
 

/**
 * Execute the first argument expression that is expected to return a
 * string.  If the argument is null, then get the string value from the
 * current context node.
 *
 * @param xctxt Runtime XPath context.
 *
 * @return The string value of the first argument, or the string value of the
 *         current context node if the first argument is null.
 *
 * @throws javax.xml.transform.TransformerException if an error occurs while
 *                                   executing the argument expression.
 */
protected XMLString getArg0AsString(XPathContext xctxt)
        throws javax.xml.transform.TransformerException
{
  if(null == m_arg0)
  {
    int currentNode = xctxt.getCurrentNode();
    if(DTM.NULL == currentNode)
      return XString.EMPTYSTRING;
    else
    {
      DTM dtm = xctxt.getDTM(currentNode);
      return dtm.getStringValue(currentNode);
    }
    
  }
  else
    return m_arg0.execute(xctxt).xstr();   
}
 

/**
 * Set the root node of the TreeWalker.
 * (Not part of the DOM2 TreeWalker interface).
 *
 * @param root The context node of this step.
 */
public void setRoot(int root)
{
  // %OPT% Get this directly from the lpi.
  XPathContext xctxt = wi().getXPathContext();
  m_dtm = xctxt.getDTM(root);
  m_traverser = m_dtm.getAxisTraverser(m_axis);
  m_isFresh = true;
  m_foundLast = false;
  m_root = root;
  m_currentNode = root;

  if (DTM.NULL == root)
  {
    throw new RuntimeException(
      XSLMessages.createXPATHMessage(XPATHErrorResources.ER_SETTING_WALKER_ROOT_TO_NULL, null)); //"\n !!!! Error! Setting the root of a walker to null!!!");
  }

  resetProximityPositions();
}
 

/**
 * Initialize the context values for this expression
 * after it is cloned.
 *
 * @param context The XPath runtime context for this
 * transformation.
 */
public void setRoot(int context, Object environment)
{

  m_context = context;
  
  XPathContext xctxt = (XPathContext)environment;
  m_execContext = xctxt;
  m_cdtm = xctxt.getDTM(context);
  
  m_currentContextNode = context; // only if top level?
  
  // Yech, shouldn't have to do this.  -sb
  if(null == m_prefixResolver)
  	m_prefixResolver = xctxt.getNamespaceContext();
      
  m_lastFetched = DTM.NULL;
  m_foundLast = false;
  m_pos = 0;
  m_length = -1;

  if (m_isTopLevel)
    this.m_stackFrame = xctxt.getVarStack().getStackFrame();
    
  // reset();
}
 

/**
 * Construct a TransformerHandlerImpl.
 *
 * @param transformer Non-null reference to the Xalan transformer impl.
 * @param doFragment True if the result should be a document fragement.
 * @param baseSystemID  The system ID to use as the base for relative URLs.
 */
public TransformerHandlerImpl(TransformerImpl transformer,
                              boolean doFragment, String baseSystemID)
{

  super();

  m_transformer = transformer;
  m_baseSystemID = baseSystemID;

  XPathContext xctxt = transformer.getXPathContext();
  DTM dtm = xctxt.getDTM(null, true, transformer, true, true);
  
  m_dtm = dtm;
  dtm.setDocumentBaseURI(baseSystemID);

  m_contentHandler = dtm.getContentHandler();
  m_dtdHandler = dtm.getDTDHandler();
  m_entityResolver = dtm.getEntityResolver();
  m_errorHandler = dtm.getErrorHandler();
  m_lexicalHandler = dtm.getLexicalHandler();
  m_incremental = transformer.getIncremental();
  m_optimizer = transformer.getOptimize();
  m_source_location = transformer.getSource_location();
}
 

/**
 * Execute the function.  The function must return
 * a valid object.
 * @param xctxt The current execution context.
 * @return A valid XObject.
 *
 * @throws javax.xml.transform.TransformerException
 */
public XObject execute(XPathContext xctxt) throws javax.xml.transform.TransformerException
{

  String lang = m_arg0.execute(xctxt).str();
  int parent = xctxt.getCurrentNode();
  boolean isLang = false;
  DTM dtm = xctxt.getDTM(parent);

  while (DTM.NULL != parent)
  {
    if (DTM.ELEMENT_NODE == dtm.getNodeType(parent))
    {
      int langAttr = dtm.getAttributeNode(parent, "http://www.w3.org/XML/1998/namespace", "lang");

      if (DTM.NULL != langAttr)
      {
        String langVal = dtm.getNodeValue(langAttr);
        // %OPT%
        if (langVal.toLowerCase().startsWith(lang.toLowerCase()))
        {
          int valLen = lang.length();

          if ((langVal.length() == valLen)
                  || (langVal.charAt(valLen) == '-'))
          {
            isLang = true;
          }
        }

        break;
      }
    }

    parent = dtm.getParent(parent);
  }

  return isLang ? XBoolean.S_TRUE : XBoolean.S_FALSE;
}
 

/**
   * Execute the function.  The function must return
   * a valid object.
   * @param xctxt The current execution context.
   * @return A valid XObject.
   *
   * @throws javax.xml.transform.TransformerException
   */
  public XObject execute(XPathContext xctxt) throws javax.xml.transform.TransformerException
  {

    int whereNode = getArg0AsNode(xctxt);
    String fileLocation = null;

    if (DTM.NULL != whereNode)
    {
      DTM dtm = xctxt.getDTM(whereNode);
      
      // %REVIEW%
      if (DTM.DOCUMENT_FRAGMENT_NODE ==  dtm.getNodeType(whereNode))
      {
        whereNode = dtm.getFirstChild(whereNode);
      }

      if (DTM.NULL != whereNode)
      {        
        fileLocation = dtm.getDocumentBaseURI();
//        int owner = dtm.getDocument();
//        fileLocation = xctxt.getSourceTreeManager().findURIFromDoc(owner);
      }
    }

    return new XString((null != fileLocation) ? fileLocation : "");
  }
 

/**
 * Execute the function.  The function must return
 * a valid object.
 * @param xctxt The current execution context.
 * @return A valid XObject.
 *
 * @throws javax.xml.transform.TransformerException
 */
public XObject execute(XPathContext xctxt) throws javax.xml.transform.TransformerException
{

  int context = getArg0AsNode(xctxt);
  
  String s;
  if(context != DTM.NULL)
  {
    DTM dtm = xctxt.getDTM(context);
    int t = dtm.getNodeType(context);
    if(t == DTM.ELEMENT_NODE)
    {
      s = dtm.getNamespaceURI(context);
    }
    else if(t == DTM.ATTRIBUTE_NODE)
    {

      // This function always returns an empty string for namespace nodes.
      // We check for those here.  Fix inspired by Davanum Srinivas.

      s = dtm.getNodeName(context);
      if(s.startsWith("xmlns:") || s.equals("xmlns"))
        return XString.EMPTYSTRING;

      s = dtm.getNamespaceURI(context);
    }
    else
      return XString.EMPTYSTRING;
  }
  else 
    return XString.EMPTYSTRING;
  
  return ((null == s) ? XString.EMPTYSTRING : new XString(s));
}
 

private final void initDTM(int root, XPathContext xctxt){
  m_dtmRoot = root;
  final DTM dtm = xctxt.getDTM(root);
  if(dtm != null){
    m_DTMXRTreeFrag = xctxt.getDTMXRTreeFrag(xctxt.getDTMIdentity(dtm));
  }
}
 

/**
 * Given a 'from' pattern (ala xsl:number), a match pattern
 * and a context, find the first ancestor that matches the
 * pattern (including the context handed in).
 *
 * @param xctxt The XPath runtime state for this.
 * @param fromMatchPattern The ancestor must match this pattern.
 * @param countMatchPattern The ancestor must also match this pattern.
 * @param context The node that "." expresses.
 * @param namespaceContext The context in which namespaces in the
 * queries are supposed to be expanded.
 *
 * @return the first ancestor that matches the given pattern
 *
 * @throws javax.xml.transform.TransformerException
 */
int findAncestor(
        XPathContext xctxt, XPath fromMatchPattern, XPath countMatchPattern, 
        int context, ElemNumber namespaceContext)
          throws javax.xml.transform.TransformerException
{
  DTM dtm = xctxt.getDTM(context);
  while (DTM.NULL != context)
  {
    if (null != fromMatchPattern)
    {
      if (fromMatchPattern.getMatchScore(xctxt, context)
              != XPath.MATCH_SCORE_NONE)
      {

        //context = null;
        break;
      }
    }

    if (null != countMatchPattern)
    {
      if (countMatchPattern.getMatchScore(xctxt, context)
              != XPath.MATCH_SCORE_NONE)
      {
        break;
      }
    }

    context = dtm.getParent(context);
  }

  return context;
}
 

/**
 * Return the first node out of the nodeset, if this expression is 
 * a nodeset expression.  This is the default implementation for 
 * nodesets.
 * <p>WARNING: Do not mutate this class from this function!</p>
 * @param xctxt The XPath runtime context.
 * @return the first node out of the nodeset, or DTM.NULL.
 */
public int asNode(XPathContext xctxt)
  throws javax.xml.transform.TransformerException
{
  int current = xctxt.getCurrentNode();
  
  DTM dtm = xctxt.getDTM(current);
  
  return dtm.getFirstChild(current);
}
 

/**
 * Return the first node out of the nodeset, if this expression is 
 * a nodeset expression.  This is the default implementation for 
 * nodesets.
 * <p>WARNING: Do not mutate this class from this function!</p>
 * @param xctxt The XPath runtime context.
 * @return the first node out of the nodeset, or DTM.NULL.
 */
public int asNode(XPathContext xctxt)
  throws javax.xml.transform.TransformerException
{
  if(getPredicateCount() > 0)
    return super.asNode(xctxt);

  int current = xctxt.getCurrentNode();
  
  DTM dtm = xctxt.getDTM(current);
  DTMAxisTraverser traverser = dtm.getAxisTraverser(m_axis);
  
  String localName = getLocalName();
  String namespace = getNamespace();
  int what = m_whatToShow;
  
  // System.out.print(" (DescendantIterator) ");
  
  // System.out.println("what: ");
  // NodeTest.debugWhatToShow(what);
  if(DTMFilter.SHOW_ALL == what
     || localName == NodeTest.WILD
     || namespace == NodeTest.WILD)
  {
    return traverser.first(current);
  }
  else
  {
    int type = getNodeTypeTest(what);
    int extendedType = dtm.getExpandedTypeID(namespace, localName, type);
    return traverser.first(current, extendedType);
  }
}
 

/**
 * Execute the function.  The function must return
 * a valid object.
 * @param xctxt The current execution context.
 * @return A valid XObject.
 *
 * @throws javax.xml.transform.TransformerException
 */
public XObject execute(XPathContext xctxt) throws javax.xml.transform.TransformerException
{

  int context = getArg0AsNode(xctxt);
  if(DTM.NULL == context)
    return XString.EMPTYSTRING;
  DTM dtm = xctxt.getDTM(context);
  String s = (context != DTM.NULL) ? dtm.getLocalName(context) : "";
  if(s.startsWith("#") || s.equals("xmlns"))
    return XString.EMPTYSTRING;

  return new XString(s);
}
 

/**
 * Given a result tree fragment, walk the tree and
 * output it to the SerializationHandler.
 *
 * @param obj Result tree fragment object
 * @param support XPath context for the result tree fragment
 *
 * @throws org.xml.sax.SAXException
 */
public static void outputResultTreeFragment(
    SerializationHandler handler,
    XObject obj,
    XPathContext support)
    throws org.xml.sax.SAXException
{

    int doc = obj.rtf();
    DTM dtm = support.getDTM(doc);

    if (null != dtm)
    {
        for (int n = dtm.getFirstChild(doc);
            DTM.NULL != n;
            n = dtm.getNextSibling(n))
        {
            handler.flushPending();

            // I think. . . . This used to have a (true) arg
            // to flush prefixes, will that cause problems ???
            if (dtm.getNodeType(n) == DTM.ELEMENT_NODE
                    && dtm.getNamespaceURI(n) == null)
                handler.startPrefixMapping("", "");
            dtm.dispatchToEvents(n, handler);
        }
    }
}
 

/**
 * Get the previous node to be counted.
 *
 * @param xctxt The XPath runtime state for this.
 * @param pos The current node
 *
 * @return the previous node to be counted.
 *
 * @throws TransformerException
 */
public int getPreviousNode(XPathContext xctxt, int pos)
        throws TransformerException
{

  XPath countMatchPattern = getCountMatchPattern(xctxt, pos);
  DTM dtm = xctxt.getDTM(pos);

  if (Constants.NUMBERLEVEL_ANY == m_level)
  {
    XPath fromMatchPattern = m_fromMatchPattern;

    // Do a backwards document-order walk 'till a node is found that matches 
    // the 'from' pattern, or a node is found that matches the 'count' pattern, 
    // or the top of the tree is found.
    while (DTM.NULL != pos)
    {

      // Get the previous sibling, if there is no previous sibling, 
      // then count the parent, but if there is a previous sibling, 
      // dive down to the lowest right-hand (last) child of that sibling.
      int next = dtm.getPreviousSibling(pos);

      if (DTM.NULL == next)
      {
        next = dtm.getParent(pos);

        if ((DTM.NULL != next) && ((((null != fromMatchPattern) && (fromMatchPattern.getMatchScore(
                xctxt, next) != XPath.MATCH_SCORE_NONE))) 
            || (dtm.getNodeType(next) == DTM.DOCUMENT_NODE)))
        {
          pos = DTM.NULL;  // return null from function.

          break;  // from while loop
        }
      }
      else
      {

        // dive down to the lowest right child.
        int child = next;

        while (DTM.NULL != child)
        {
          child = dtm.getLastChild(next);

          if (DTM.NULL != child)
            next = child;
        }
      }

      pos = next;

      if ((DTM.NULL != pos)
              && ((null == countMatchPattern)
                  || (countMatchPattern.getMatchScore(xctxt, pos)
                      != XPath.MATCH_SCORE_NONE)))
      {
        break;
      }
    }
  }
  else  // NUMBERLEVEL_MULTI or NUMBERLEVEL_SINGLE
  {
    while (DTM.NULL != pos)
    {
      pos = dtm.getPreviousSibling(pos);

      if ((DTM.NULL != pos)
              && ((null == countMatchPattern)
                  || (countMatchPattern.getMatchScore(xctxt, pos)
                      != XPath.MATCH_SCORE_NONE)))
      {
        break;
      }
    }
  }

  return pos;
}
 

/**
 * Get the ancestors, up to the root, that match the
 * pattern.
 * 
 * @param xctxt The XPath runtime state for this.
 * @param node Count this node and it's ancestors.
 * @param stopAtFirstFound Flag indicating to stop after the
 * first node is found (difference between level = single
 * or multiple)
 * @return The number of ancestors that match the pattern.
 *
 * @throws javax.xml.transform.TransformerException
 */
NodeVector getMatchingAncestors(
        XPathContext xctxt, int node, boolean stopAtFirstFound)
          throws javax.xml.transform.TransformerException
{

  NodeSetDTM ancestors = new NodeSetDTM(xctxt.getDTMManager());
  XPath countMatchPattern = getCountMatchPattern(xctxt, node);
  DTM dtm = xctxt.getDTM(node);

  while (DTM.NULL != node)
  {
    if ((null != m_fromMatchPattern)
            && (m_fromMatchPattern.getMatchScore(xctxt, node)
                != XPath.MATCH_SCORE_NONE))
    {

      // The following if statement gives level="single" different 
      // behavior from level="multiple", which seems incorrect according 
      // to the XSLT spec.  For now we are leaving this in to replicate 
      // the same behavior in XT, but, for all intents and purposes we 
      // think this is a bug, or there is something about level="single" 
      // that we still don't understand.
      if (!stopAtFirstFound)
        break;
    }

    if (null == countMatchPattern)
      System.out.println(
        "Programmers error! countMatchPattern should never be null!");

    if (countMatchPattern.getMatchScore(xctxt, node)
            != XPath.MATCH_SCORE_NONE)
    {
      ancestors.addElement(node);

      if (stopAtFirstFound)
        break;
    }

    node = dtm.getParent(node);
  }

  return ancestors;
}
 

/**
 * Given a 'from' pattern (ala xsl:number), a match pattern
 * and a context, find the first ancestor that matches the
 * pattern (including the context handed in).
 * @param xctxt The XPath runtime state for this.
 * @param fromMatchPattern The ancestor must match this pattern.
 * @param countMatchPattern The ancestor must also match this pattern.
 * @param context The node that "." expresses.
 * @param namespaceContext The context in which namespaces in the
 * queries are supposed to be expanded.
 *
 * @return the first preceding, ancestor or self node that 
 * matches the given pattern
 *
 * @throws javax.xml.transform.TransformerException
 */
private int findPrecedingOrAncestorOrSelf(
        XPathContext xctxt, XPath fromMatchPattern, XPath countMatchPattern, 
        int context, ElemNumber namespaceContext)
          throws javax.xml.transform.TransformerException
{
  DTM dtm = xctxt.getDTM(context);
  while (DTM.NULL != context)
  {
    if (null != fromMatchPattern)
    {
      if (fromMatchPattern.getMatchScore(xctxt, context)
              != XPath.MATCH_SCORE_NONE)
      {
        context = DTM.NULL;

        break;
      }
    }

    if (null != countMatchPattern)
    {
      if (countMatchPattern.getMatchScore(xctxt, context)
              != XPath.MATCH_SCORE_NONE)
      {
        break;
      }
    }

    int prevSibling = dtm.getPreviousSibling(context);

    if (DTM.NULL == prevSibling)
    {
      context = dtm.getParent(context);
    }
    else
    {

      // Now go down the chain of children of this sibling 
      context = dtm.getLastChild(prevSibling);

      if (context == DTM.NULL)
        context = prevSibling;
    }
  }

  return context;
}
 

public DTMXRTreeFrag(int dtmIdentity, XPathContext xctxt){
  m_xctxt = xctxt;
  m_dtmIdentity = dtmIdentity;
  m_dtm = xctxt.getDTM(dtmIdentity); 
}
 

/**
 * The xsl:copy element provides an easy way of copying the current node.
 * Executing this function creates a copy of the current node into the
 * result tree.
 * <p>The namespace nodes of the current node are automatically
 * copied as well, but the attributes and children of the node are not
 * automatically copied. The content of the xsl:copy element is a
 * template for the attributes and children of the created node;
 * the content is instantiated only for nodes of types that can have
 * attributes or children (i.e. root nodes and element nodes).</p>
 * <p>The root node is treated specially because the root node of the
 * result tree is created implicitly. When the current node is the
 * root node, xsl:copy will not create a root node, but will just use
 * the content template.</p>
 *
 * @param transformer non-null reference to the the current transform-time state.
 *
 * @throws TransformerException
 */
public void execute(
        TransformerImpl transformer)
          throws TransformerException
{
              XPathContext xctxt = transformer.getXPathContext();
    
  try
  {
    int sourceNode = xctxt.getCurrentNode();
    xctxt.pushCurrentNode(sourceNode);
    DTM dtm = xctxt.getDTM(sourceNode);
    short nodeType = dtm.getNodeType(sourceNode);

    if ((DTM.DOCUMENT_NODE != nodeType) && (DTM.DOCUMENT_FRAGMENT_NODE != nodeType))
    {
      SerializationHandler rthandler = transformer.getSerializationHandler();

      // TODO: Process the use-attribute-sets stuff
      ClonerToResultTree.cloneToResultTree(sourceNode, nodeType, dtm, 
                                           rthandler, false);

      if (DTM.ELEMENT_NODE == nodeType)
      {
        super.execute(transformer);
        SerializerUtils.processNSDecls(rthandler, sourceNode, nodeType, dtm);
        transformer.executeChildTemplates(this, true);
        
        String ns = dtm.getNamespaceURI(sourceNode);
        String localName = dtm.getLocalName(sourceNode);
        transformer.getResultTreeHandler().endElement(ns, localName,
                                                      dtm.getNodeName(sourceNode));
      }
    }
    else
    {
      super.execute(transformer);
      transformer.executeChildTemplates(this, true);
    }
  }
  catch(org.xml.sax.SAXException se)
  {
    throw new TransformerException(se);
  }
  finally
  {
    xctxt.popCurrentNode();
  }
}
 

/**
   * Fill in a list with nodes that match a space delimited list if ID 
   * ID references.
   *
   * @param xctxt The runtime XPath context.
   * @param docContext The document where the nodes are being looked for.
   * @param refval A space delimited list of ID references.
   * @param usedrefs List of references for which nodes were found.
   * @param nodeSet Node set where the nodes will be added to.
   * @param mayBeMore true if there is another set of nodes to be looked for.
   *
   * @return The usedrefs value.
   */
  private StringVector getNodesByID(XPathContext xctxt, int docContext,
                                    String refval, StringVector usedrefs,
                                    NodeSetDTM nodeSet, boolean mayBeMore)
  {

    if (null != refval)
    {
      String ref = null;
//      DOMHelper dh = xctxt.getDOMHelper();
      StringTokenizer tokenizer = new StringTokenizer(refval);
      boolean hasMore = tokenizer.hasMoreTokens();
      DTM dtm = xctxt.getDTM(docContext);

      while (hasMore)
      {
        ref = tokenizer.nextToken();
        hasMore = tokenizer.hasMoreTokens();

        if ((null != usedrefs) && usedrefs.contains(ref))
        {
          ref = null;

          continue;
        }

        int node = dtm.getElementById(ref);

        if (DTM.NULL != node)
          nodeSet.addNodeInDocOrder(node, xctxt);

        if ((null != ref) && (hasMore || mayBeMore))
        {
          if (null == usedrefs)
            usedrefs = new StringVector();

          usedrefs.addElement(ref);
        }
      }
    }

    return usedrefs;
  }