text: /*
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements. See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership. The ASF licenses this file
   * to you under the Apache License, Version 2.0 (the  "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  /*
   * $Id: AVTPartXPath.java 468643 2006-10-28 06:56:03Z minchau $
   */
  package org.apache.xalan.templates;
  
  import org.apache.xml.utils.FastStringBuffer;
  import org.apache.xpath.XPath;
  import org.apache.xpath.XPathContext;
  import org.apache.xpath.XPathFactory;
  import org.apache.xpath.compiler.XPathParser;
  import org.apache.xpath.objects.XObject;
  
  /**
   * Simple string part of a complex AVT.
   * @xsl.usage internal
   */
  public class AVTPartXPath extends AVTPart
  {
      static final long serialVersionUID = -4460373807550527675L;
  
    /**
     * The XPath object contained in this part.
     * @serial
     */
    private XPath m_xpath;
    
    /**
     * This function is used to fixup variables from QNames to stack frame 
     * indexes at stylesheet build time.
     * @param vars List of QNames that correspond to variables.  This list 
     * should be searched backwards for the first qualified name that 
     * corresponds to the variable reference qname.  The position of the 
     * QName in the vector from the start of the vector will be its position 
     * in the stack frame (but variables above the globalsTop value will need 
     * to be offset to the current stack frame).
     */
    public void fixupVariables(java.util.Vector vars, int globalsSize)
    {
      m_xpath.fixupVariables(vars, globalsSize);
    }
    
    /**
     * Tell if this expression or it's subexpressions can traverse outside 
     * the current subtree.
     * 
     * @return true if traversal outside the context node's subtree can occur.
     */
     public boolean canTraverseOutsideSubtree()
     {
      return m_xpath.getExpression().canTraverseOutsideSubtree();
     }
  
    /**
     * Construct a simple AVT part.
     *
     * @param xpath Xpath section of AVT 
     */
    public AVTPartXPath(XPath xpath)
    {
      m_xpath = xpath;
    }
  
    /**
     * Construct a simple AVT part.
     * 
     * @param val A pure string section of an AVT.
     * @param nsNode An object which can be used to determine the
     * Namespace Name (URI) for any Namespace prefix used in the XPath. 
     * Usually this is based on the context where the XPath was specified,
     * such as a node within a Stylesheet.
     * @param xpathProcessor XPath parser
     * @param factory XPath factory
     * @param liaison An XPathContext object, providing infomation specific
     * to this invocation and this thread. Maintains SAX output state, 
     * variables, error handler and so on, so the transformation/XPath 
     * object itself can be simultaneously invoked from multiple threads.
     *
     * @throws javax.xml.transform.TransformerException
     * TODO: Fix or remove this unused c'tor.
     */
    public AVTPartXPath(
            String val, org.apache.xml.utils.PrefixResolver nsNode, 
            XPathParser xpathProcessor, XPathFactory factory, 
            XPathContext liaison)
              throws javax.xml.transform.TransformerException
    {
      m_xpath = new XPath(val, null, nsNode, XPath.SELECT, liaison.getErrorListener());
    }
  
    /**
     * Get the AVT part as the original string.
     *
     * @return the AVT part as the original string.
     */
    public String getSimpleString()
    {
      return "{" + m_xpath.getPatternString() + "}";
    }
  
    /**
     * Write the value into the buffer.
     *
     * @param xctxt An XPathContext object, providing infomation specific
     * to this invocation and this thread. Maintains SAX state, variables, 
     * error handler and  so on, so the transformation/XPath object itself
     * can be simultaneously invoked from multiple threads.
     * @param buf Buffer to write into.
     * @param context The current source tree context.
     * @param nsNode The current namespace context (stylesheet tree context).
     *
     * @throws javax.xml.transform.TransformerException
     */
    public void evaluate(
            XPathContext xctxt, FastStringBuffer buf, int context, org.apache.xml.utils.PrefixResolver nsNode)
              throws javax.xml.transform.TransformerException
    {
  
      XObject xobj = m_xpath.execute(xctxt, context, nsNode);
  
      if (null != xobj)
      {
        xobj.appendToFsb(buf);
      }
    }
    
    /**
     * @see XSLTVisitable#callVisitors(XSLTVisitor)
     */
    public void callVisitors(XSLTVisitor visitor)
    {
    	m_xpath.getExpression().callVisitors(m_xpath, visitor);
    }
  }
  