transformerimpl.java

来自「java jdk 1.4的源码」· Java 代码 · 共 2,145 行 · 第 1/5 页

      m_xcontext.getSourceTreeManager().setURIResolver(resolver);
    }
  }

  /**
   * Get an object that will be used to resolve URIs used in
   * document(), etc.
   *
   * @return An object that implements the URIResolver interface,
   * or null.
   */
  public URIResolver getURIResolver()
  {
    return m_xcontext.getSourceTreeManager().getURIResolver();
  }

  // ======== End Transformer Implementation ========  

  /**
   * Set the content event handler.
   *
   * @param resolver The new content handler.
   *
   * NEEDSDOC @param handler
   * @throws java.lang.NullPointerException If the handler
   *            is null.
   * @see org.xml.sax.XMLReader#setContentHandler
   */
  public void setContentHandler(ContentHandler handler)
  {

    if (handler == null)
    {
      throw new NullPointerException(XSLMessages.createMessage(XSLTErrorResources.ER_NULL_CONTENT_HANDLER, null)); //"Null content handler");
    }
    else
    {
      m_outputContentHandler = handler;

      if (null == m_resultTreeHandler)
        m_resultTreeHandler = new ResultTreeHandler(this, handler);
      else
        m_resultTreeHandler.setContentHandler(handler);
    }
  }

  /**
   * Get the content event handler.
   *
   * @return The current content handler, or null if none was set.
   * @see org.xml.sax.XMLReader#getContentHandler
   */
  public ContentHandler getContentHandler()
  {
    return m_outputContentHandler;
  }

  /**
   * <meta name="usage" content="advanced"/>
   * Given a stylesheet element, create a result tree fragment from it's
   * contents. The fragment will be built within the shared RTF DTM system
   * used as a variable stack.
   * @param templateParent The template element that holds the fragment.
   * @return the NodeHandle for the root node of the resulting RTF.
   *
   * @throws TransformerException
   */
  public int transformToRTF(ElemTemplateElement templateParent)
          throws TransformerException
  {
    // Retrieve a DTM to contain the RTF. At this writing, this may be a
    // multi-document DTM (SAX2RTFDTM).
    DTM dtmFrag = m_xcontext.getRTFDTM();
    return transformToRTF(templateParent,dtmFrag);
  }
  
  /**
   * <meta name="usage" content="advanced"/>
   * Given a stylesheet element, create a result tree fragment from it's
   * contents. The fragment will also use the shared DTM system, but will
   * obtain its space from the global variable pool rather than the dynamic
   * variable stack. This allows late binding of XUnresolvedVariables without
   * the risk that their content will be discarded when the variable stack
   * is popped.
   * 
   * @param templateParent The template element that holds the fragment.
   * @return the NodeHandle for the root node of the resulting RTF.
   *
   * @throws TransformerException
   */
  public int transformToGlobalRTF(ElemTemplateElement templateParent)
          throws TransformerException
  {
    // Retrieve a DTM to contain the RTF. At this writing, this may be a
    // multi-document DTM (SAX2RTFDTM).
    DTM dtmFrag = m_xcontext.getGlobalRTFDTM();
    return transformToRTF(templateParent,dtmFrag);
  }
  
  /**
   * <meta name="usage" content="advanced"/>
   * Given a stylesheet element, create a result tree fragment from it's
   * contents.
   * @param templateParent The template element that holds the fragment.
   * @param dtmFrag The DTM to write the RTF into
   * @return the NodeHandle for the root node of the resulting RTF.
   *
   * @throws TransformerException
   */
  private int transformToRTF(ElemTemplateElement templateParent,DTM dtmFrag)
          throws TransformerException
  {

    XPathContext xctxt = m_xcontext;
    
    ContentHandler rtfHandler = dtmFrag.getContentHandler();

    // Obtain the ResultTreeFrag's root node.
    // NOTE: In SAX2RTFDTM, this value isn't available until after
    // the startDocument has been issued, so assignment has been moved
    // down a bit in the code.
    int resultFragment; // not yet reliably = dtmFrag.getDocument();

    // Save the current result tree handler.
    ResultTreeHandler savedRTreeHandler = this.m_resultTreeHandler;

    // And make a new handler for the RTF.
    m_resultTreeHandler = new ResultTreeHandler(this, rtfHandler);

    ResultTreeHandler rth = m_resultTreeHandler;

    try
    {
      rth.startDocument();
      
      // startDocument is "bottlenecked" in RTH. We need it acted upon immediately,
      // to set the DTM's state as in-progress, so that if the xsl:variable's body causes
      // further RTF activity we can keep that from bashing this DTM.
      rth.flushPending(); 
 
      try
      {

        // Do the transformation of the child elements.
        executeChildTemplates(templateParent, true);

        // Make sure everything is flushed!
        rth.flushPending();
        
        // Get the document ID. May not exist until the RTH has not only
        // received, but flushed, the startDocument, and may be invalid
        // again after the document has been closed (still debating that)
        // ... so waiting until just before the end seems simplest/safest. 
	resultFragment = dtmFrag.getDocument();      
      }
      finally
      {
        rth.endDocument();
      }
    }
    catch (org.xml.sax.SAXException se)
    {
      throw new TransformerException(se);
    }
    finally
    {

      // Restore the previous result tree handler.
      this.m_resultTreeHandler = savedRTreeHandler;
    }

    return resultFragment;
  }

  /**
   * <meta name="usage" content="internal"/>
   * Get the StringWriter pool, so that StringWriter
   * objects may be reused.
   *
   * @return The string writer pool, not null.
   */
  public ObjectPool getStringWriterPool()
  {
    return m_stringWriterObjectPool;
  }

  /**
   * <meta name="usage" content="advanced"/>
   * Take the contents of a template element, process it, and
   * convert it to a string.
   *
   * @param elem The parent element whose children will be output
   * as a string.
   * @param transformer The XSLT transformer instance.
   * @param sourceNode The current source node context.
   * @param mode The current xslt mode.
   *
   * @return The stringized result of executing the elements children.
   *
   * @throws TransformerException
   */
  public String transformToString(ElemTemplateElement elem)
          throws TransformerException
  {
    ElemTemplateElement firstChild = elem.getFirstChildElem();
    if(null == firstChild)
      return "";
    if(elem.hasTextLitOnly() && org.apache.xalan.processor.TransformerFactoryImpl.m_optimize)
    {
      return ((ElemTextLiteral)firstChild).getNodeValue();
    }

    // Save the current result tree handler.
    ResultTreeHandler savedRTreeHandler = this.m_resultTreeHandler;

    // Create a Serializer object that will handle the SAX events 
    // and build the ResultTreeFrag nodes.
    StringWriter sw = (StringWriter) m_stringWriterObjectPool.getInstance();

    m_resultTreeHandler =
      (ResultTreeHandler) m_textResultHandlerObjectPool.getInstance();

    Serializer serializer = m_resultTreeHandler.getSerializer();

    try
    {
      if (null == serializer)
      {
        serializer =
          SerializerFactory.getSerializer(m_textformat.getProperties());

        m_resultTreeHandler.setSerializer(serializer);
        serializer.setWriter(sw);

        ContentHandler shandler = serializer.asContentHandler();

        m_resultTreeHandler.init(this, shandler);
      }
      else
      {

        // Leave Commented.  -sb
        // serializer.setWriter(sw);
        // serializer.setOutputFormat(m_textformat);
        // ContentHandler shandler = serializer.asContentHandler();
        // m_resultTreeHandler.setContentHandler(shandler);
      }
    }
    catch (IOException ioe)
    {
      throw new TransformerException(ioe);
    }

    String result;

    try
    {
      this.m_resultTreeHandler.startDocument();

      // Do the transformation of the child elements.
      executeChildTemplates(elem, true);
      this.m_resultTreeHandler.endDocument();

      result = sw.toString();
    }
    catch (org.xml.sax.SAXException se)
    {
      throw new TransformerException(se);
    }
    finally
    {
      sw.getBuffer().setLength(0);

      try
      {
        sw.close();
      }
      catch (Exception ioe){}

      m_stringWriterObjectPool.freeInstance(sw);
      m_textResultHandlerObjectPool.freeInstance(m_resultTreeHandler);
      m_resultTreeHandler.reset();

      // Restore the previous result tree handler.
      m_resultTreeHandler = savedRTreeHandler;
    }

    return result;
  }

  /**
   * <meta name="usage" content="advanced"/>
   * Given an element and mode, find the corresponding
   * template and process the contents.
   *
   * @param xslInstruction The calling element.
   * @param template The template to use if xsl:for-each, or null.
   * @param child The source context node.
   * @param mode The current mode, may be null.
   * @throws TransformerException
   * @return true if applied a template, false if not.
   */
  public boolean applyTemplateToNode(ElemTemplateElement xslInstruction,  // xsl:apply-templates or xsl:for-each
                                     ElemTemplate template, int child)
                                             throws TransformerException
  {

    DTM dtm = m_xcontext.getDTM(child);
    short nodeType = dtm.getNodeType(child);
    boolean isDefaultTextRule = false;
    boolean isApplyImports = false;    

    if (null == template)
    {
      int maxImportLevel, endImportLevel=0;
      isApplyImports = ((xslInstruction == null)
                                ? false
                                : xslInstruction.getXSLToken()
                                  == Constants.ELEMNAME_APPLY_IMPORTS);

      if (isApplyImports)
      {
        maxImportLevel =
          xslInstruction.getStylesheetComposed().getImportCountComposed() - 1;
        endImportLevel =
          xslInstruction.getStylesheetComposed().getEndImportCountComposed();
      }
      else
      {
        maxImportLevel = -1;
      }

      // If we're trying an xsl:apply-imports at the top level (ie there are no
      // imported stylesheets), we need to indicate that there is no matching template.
      // The above logic will calculate a maxImportLevel of -1 which indicates
      // that we should find any template.  This is because a value of -1 for
      // maxImportLevel has a special meaning.  But we don't want that.
      // We want to match -no- templates. See bugzilla bug 1170.
      if (isApplyImports && (maxImportLevel == -1))
      {
        template = null;
      }
      else
      {

        // Find the XSL template that is the best match for the 
        // element.        
        XPathContext xctxt = m_xcontext;

        try
        {
          xctxt.pushNamespaceContext(xslInstruction);

          QName mode = this.getMode();
          
          if (isApplyImports)
            template = m_stylesheetRoot.getTemplateComposed(xctxt, child, mode,
                  maxImportLevel, endImportLevel, m_quietConflictWarnings, dtm);
          else
            template = m_stylesheetRoot.getTemplateComposed(xctxt, child, mode,
                  m_quietConflictWarnings, dtm);
          
        }
        finally
        {
          xctxt.popNamespaceContext();
        }
      }

      // If that didn't locate a node, fall back to a default template rule.
      // See http://www.w3.org/TR/xslt#built-in-rule.
      if (null == template)
      {
        switch (nodeType)
        {
        case DTM.DOCUMENT_FRAGMENT_NODE :
        case DTM.ELEMENT_NODE :
          template = m_stylesheetRoot.getDefaultRule();
          break;
        case DTM.CDATA_SECTION_NODE :
        case DTM.TEXT_NODE :
        case DTM.ATTRIBUTE_NODE :
          template = m_stylesheetRoot.getDefaultTextRule();
          isDefaultTextRule = true;
          break;
        case DTM.DOCUMENT_NODE :
          template = m_stylesheetRoot.getDefaultRootRule();
          break;
        default :

          // No default rules for processing instructions and the like.
          return false;
        }
      }
    }

    // If we are processing the default text rule, then just clone 
    // the value directly to the result tree.
    try
    {
      pushElemTemplateElement(template);
      m_xcontext.pushCurrentNode(child);
      pushPairCurrentMatched(template, child);
      
      // Fix copy copy29 test.
      if (!isApplyImports) {
          DTMIterator cnl = new org.apache.xpath.NodeSetDTM(child, m_xcontext.getDTMManager());
          m_xcontext.pushContextNodeList(cnl);
      }

      if (isDefaultTextRule)
      {
        switch (nodeType)
        {
        case DTM.CDATA_SECTION_NODE :
        case DTM.TEXT_NODE :
          ClonerToResultTree.cloneToResultTree(child, nodeType, 
                                        dtm, getResultTreeHandler(), false);
          break;
        case DTM.ATTRIBUTE_NODE :
          dtm.dispatchCharactersEvents(child, getResultTreeHandler(), false);
          break;
        }
      }
      else
      {

        // Fire a trace event for the template.