FileDocCategorySizeDatePackage
TreeWalker.javaAPI DocJava SE 5 API13572Fri Aug 26 14:56:04 BST 2005com.sun.org.apache.xml.internal.utils

TreeWalker

public class TreeWalker extends Object
This class does a pre-order walk of the DOM tree, calling a ContentHandler interface as it goes.
xsl.usage
advanced

Fields Summary
private ContentHandler
m_contentHandler
Local reference to a ContentHandler
protected DOMHelper
m_dh
DomHelper for this TreeWalker
private LocatorImpl
m_locator
Locator object for this TreeWalker
boolean
nextIsRaw
Flag indicating whether following text to be processed is raw text
Constructors Summary
public TreeWalker(ContentHandler contentHandler, DOMHelper dh, String systemId)
Constructor.

param
contentHandler The implemention of the
param
systemId System identifier for the document. contentHandler operation (toXMLString, digest, ...)

    this.m_contentHandler = contentHandler;
    m_contentHandler.setDocumentLocator(m_locator);
    if (systemId != null)
        m_locator.setSystemId(systemId);
    else {
        try {
          // Bug see Bugzilla  26741
          m_locator.setSystemId(System.getProperty("user.dir") + File.separator + "dummy.xsl");
         }
         catch (SecurityException se) {// user.dir not accessible from applet             
         }
    }
    m_dh = dh;
public TreeWalker(ContentHandler contentHandler, DOMHelper dh)
Constructor.

param
contentHandler The implemention of the contentHandler operation (toXMLString, digest, ...)

    this.m_contentHandler = contentHandler;
    m_contentHandler.setDocumentLocator(m_locator);
    try {
       // Bug see Bugzilla  26741
      m_locator.setSystemId(System.getProperty("user.dir") + File.separator + "dummy.xsl");
    } 
    catch (SecurityException se){// user.dir not accessible from applet      
    }
    m_dh = dh;
public TreeWalker(ContentHandler contentHandler)
Constructor.

param
contentHandler The implemention of the contentHandler operation (toXMLString, digest, ...)

    this.m_contentHandler = contentHandler;
                if (m_contentHandler != null)
                        m_contentHandler.setDocumentLocator(m_locator);
                try {
                   // Bug see Bugzilla  26741
                  m_locator.setSystemId(System.getProperty("user.dir") + File.separator + "dummy.xsl");
                } 
                catch (SecurityException se){// user.dir not accessible from applet
                  
    }
    m_dh = new DOM2Helper();
Methods Summary
private final voiddispatachChars(org.w3c.dom.Node node)
Optimized dispatch of characters.

  
         
      
      
  
    if(m_contentHandler instanceof com.sun.org.apache.xml.internal.dtm.ref.dom2dtm.DOM2DTM.CharacterNodeHandler)
    {
      ((com.sun.org.apache.xml.internal.dtm.ref.dom2dtm.DOM2DTM.CharacterNodeHandler)m_contentHandler).characters(node);
    }
    else
    {
      String data = ((Text) node).getData();
      this.m_contentHandler.characters(data.toCharArray(), 0, data.length());
    }
protected voidendNode(org.w3c.dom.Node node)
End processing of given node

param
node Node we just finished processing
throws
org.xml.sax.SAXException


    switch (node.getNodeType())
    {
    case Node.DOCUMENT_NODE :
      break;
      
    case Node.ELEMENT_NODE :
      String ns = m_dh.getNamespaceOfNode(node);
      if(null == ns)
        ns = "";
      this.m_contentHandler.endElement(ns,
                                         m_dh.getLocalNameOfNode(node),
                                         node.getNodeName());

      NamedNodeMap atts = ((Element) node).getAttributes();
      int nAttrs = atts.getLength();

      for (int i = 0; i < nAttrs; i++)
      {
        Node attr = atts.item(i);
        String attrName = attr.getNodeName();

        if (attrName.equals("xmlns") || attrName.startsWith("xmlns:"))
        {
          int index;
          // Use "" instead of null, as Xerces likes "" for the 
          // name of the default namespace.  Fix attributed 
          // to "Steven Murray" <smurray@ebt.com>.
          String prefix = (index = attrName.indexOf(":")) < 0
                          ? "" : attrName.substring(index + 1);

          this.m_contentHandler.endPrefixMapping(prefix);
        }
      }
      break;
    case Node.CDATA_SECTION_NODE :
      break;
    case Node.ENTITY_REFERENCE_NODE :
    {
      EntityReference eref = (EntityReference) node;

      if (m_contentHandler instanceof LexicalHandler)
      {
        LexicalHandler lh = ((LexicalHandler) this.m_contentHandler);

        lh.endEntity(eref.getNodeName());
      }
    }
    break;
    default :
    }
public org.xml.sax.ContentHandlergetContentHandler()
Get the ContentHandler used for the tree walk.

return
the ContentHandler used for the tree walk


                     
    
  
    return m_contentHandler;
public voidsetContentHandler(org.xml.sax.ContentHandler ch)
Get the ContentHandler used for the tree walk.

return
the ContentHandler used for the tree walk

    m_contentHandler = ch;
protected voidstartNode(org.w3c.dom.Node node)
Start processing given node

param
node Node to process
throws
org.xml.sax.SAXException


    if (m_contentHandler instanceof NodeConsumer)
    {
      ((NodeConsumer) m_contentHandler).setOriginatingNode(node);
    }
                
                if (node instanceof Locator)
                {
                        Locator loc = (Locator)node;
                        m_locator.setColumnNumber(loc.getColumnNumber());
                        m_locator.setLineNumber(loc.getLineNumber());
                        m_locator.setPublicId(loc.getPublicId());
                        m_locator.setSystemId(loc.getSystemId());
                }
                else
                {
                        m_locator.setColumnNumber(0);
      m_locator.setLineNumber(0);
                }

    switch (node.getNodeType())
    {
    case Node.COMMENT_NODE :
    {
      String data = ((Comment) node).getData();

      if (m_contentHandler instanceof LexicalHandler)
      {
        LexicalHandler lh = ((LexicalHandler) this.m_contentHandler);

        lh.comment(data.toCharArray(), 0, data.length());
      }
    }
    break;
    case Node.DOCUMENT_FRAGMENT_NODE :

      // ??;
      break;
    case Node.DOCUMENT_NODE :
    
      break;
    case Node.ELEMENT_NODE :
      NamedNodeMap atts = ((Element) node).getAttributes();
      int nAttrs = atts.getLength();
      // System.out.println("TreeWalker#startNode: "+node.getNodeName());

      for (int i = 0; i < nAttrs; i++)
      {
        Node attr = atts.item(i);
        String attrName = attr.getNodeName();

        // System.out.println("TreeWalker#startNode: attr["+i+"] = "+attrName+", "+attr.getNodeValue());
        if (attrName.equals("xmlns") || attrName.startsWith("xmlns:"))
        {
          // System.out.println("TreeWalker#startNode: attr["+i+"] = "+attrName+", "+attr.getNodeValue());
          int index;
          // Use "" instead of null, as Xerces likes "" for the 
          // name of the default namespace.  Fix attributed 
          // to "Steven Murray" <smurray@ebt.com>.
          String prefix = (index = attrName.indexOf(":")) < 0
                          ? "" : attrName.substring(index + 1);

          this.m_contentHandler.startPrefixMapping(prefix,
                                                   attr.getNodeValue());
        }
        
      }

      // System.out.println("m_dh.getNamespaceOfNode(node): "+m_dh.getNamespaceOfNode(node));
      // System.out.println("m_dh.getLocalNameOfNode(node): "+m_dh.getLocalNameOfNode(node));
      String ns = m_dh.getNamespaceOfNode(node);
      if(null == ns)
        ns = "";
      this.m_contentHandler.startElement(ns,
                                         m_dh.getLocalNameOfNode(node),
                                         node.getNodeName(),
                                         new AttList(atts, m_dh));
      break;
    case Node.PROCESSING_INSTRUCTION_NODE :
    {
      ProcessingInstruction pi = (ProcessingInstruction) node;
      String name = pi.getNodeName();

      // String data = pi.getData();
      if (name.equals("xslt-next-is-raw"))
      {
        nextIsRaw = true;
      }
      else
      {
        this.m_contentHandler.processingInstruction(pi.getNodeName(),
                                                    pi.getData());
      }
    }
    break;
    case Node.CDATA_SECTION_NODE :
    {
      boolean isLexH = (m_contentHandler instanceof LexicalHandler);
      LexicalHandler lh = isLexH
                          ? ((LexicalHandler) this.m_contentHandler) : null;

      if (isLexH)
      {
        lh.startCDATA();
      }
      
      dispatachChars(node);

      {
        if (isLexH)
        {
          lh.endCDATA();
        }
      }
    }
    break;
    case Node.TEXT_NODE :
    {
      //String data = ((Text) node).getData();

      if (nextIsRaw)
      {
        nextIsRaw = false;

        m_contentHandler.processingInstruction(javax.xml.transform.Result.PI_DISABLE_OUTPUT_ESCAPING, "");
        dispatachChars(node);
        m_contentHandler.processingInstruction(javax.xml.transform.Result.PI_ENABLE_OUTPUT_ESCAPING, "");
      }
      else
      {
        dispatachChars(node);
      }
    }
    break;
    case Node.ENTITY_REFERENCE_NODE :
    {
      EntityReference eref = (EntityReference) node;

      if (m_contentHandler instanceof LexicalHandler)
      {
        ((LexicalHandler) this.m_contentHandler).startEntity(
          eref.getNodeName());
      }
      else
      {

        // warning("Can not output entity to a pure SAX ContentHandler");
      }
    }
    break;
    default :
    }
public voidtraverse(org.w3c.dom.Node pos)
Perform a pre-order traversal non-recursive style. Note that TreeWalker assumes that the subtree is intended to represent a complete (though not necessarily well-formed) document and, during a traversal, startDocument and endDocument will always be issued to the SAX listener.

param
pos Node in the tree where to start traversal
throws
TransformerException


   	this.m_contentHandler.startDocument();

    Node top = pos;

    while (null != pos)
    {
      startNode(pos);

      Node nextNode = pos.getFirstChild();

      while (null == nextNode)
      {
        endNode(pos);

        if (top.equals(pos))
          break;

        nextNode = pos.getNextSibling();

        if (null == nextNode)
        {
          pos = pos.getParentNode();

          if ((null == pos) || (top.equals(pos)))
          {
            if (null != pos)
              endNode(pos);

            nextNode = null;

            break;
          }
        }
      }

      pos = nextNode;
    }
    this.m_contentHandler.endDocument();
public voidtraverse(org.w3c.dom.Node pos, org.w3c.dom.Node top)
Perform a pre-order traversal non-recursive style. Note that TreeWalker assumes that the subtree is intended to represent a complete (though not necessarily well-formed) document and, during a traversal, startDocument and endDocument will always be issued to the SAX listener.

param
pos Node in the tree where to start traversal
param
top Node in the tree where to end traversal
throws
TransformerException


	this.m_contentHandler.startDocument();
	
    while (null != pos)
    {
      startNode(pos);

      Node nextNode = pos.getFirstChild();

      while (null == nextNode)
      {
        endNode(pos);

        if ((null != top) && top.equals(pos))
          break;

        nextNode = pos.getNextSibling();

        if (null == nextNode)
        {
          pos = pos.getParentNode();

          if ((null == pos) || ((null != top) && top.equals(pos)))
          {
            nextNode = null;

            break;
          }
        }
      }

      pos = nextNode;
    }
    this.m_contentHandler.endDocument();