com.sun.org.apache.xpath.internal.XPathContext Java Examples

/**
 * 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);
  XObject val;

  if (DTM.NULL != context)
  {
    DTM dtm = xctxt.getDTM(context);
    String qname = dtm.getNodeNameX(context);
    val = (null == qname) ? XString.EMPTYSTRING : new XString(qname);
  }
  else
  {
    val = XString.EMPTYSTRING;
  }

  return val;
}
 

/**
 * Get the match score of the given node.
 *
 * @param xctxt The XPath runtime context.
 * @param context The node to be tested.
 *
 * @return {@link com.sun.org.apache.xpath.internal.patterns.NodeTest#SCORE_NODETEST},
 *         {@link com.sun.org.apache.xpath.internal.patterns.NodeTest#SCORE_NONE},
 *         {@link com.sun.org.apache.xpath.internal.patterns.NodeTest#SCORE_NSWILD},
 *         {@link com.sun.org.apache.xpath.internal.patterns.NodeTest#SCORE_QNAME}, or
 *         {@link com.sun.org.apache.xpath.internal.patterns.NodeTest#SCORE_OTHER}.
 *
 * @throws javax.xml.transform.TransformerException
 */
public double getMatchScore(XPathContext xctxt, int context)
        throws javax.xml.transform.TransformerException
{

  xctxt.pushCurrentNode(context);
  xctxt.pushCurrentExpressionNode(context);

  try
  {
    XObject score = execute(xctxt);

    return score.num();
  }
  finally
  {
    xctxt.popCurrentNode();
    xctxt.popCurrentExpressionNode();
  }

  // return XPath.MATCH_SCORE_NONE;
}
 

/**
 * Execute the first argument expression that is expected to return a
 * number.  If the argument is null, then get the number value from the
 * current context node.
 *
 * @param xctxt Runtime XPath context.
 *
 * @return The number value of the first argument, or the number 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 double getArg0AsNumber(XPathContext xctxt)
        throws javax.xml.transform.TransformerException
{

  if(null == m_arg0)
  {
    int currentNode = xctxt.getCurrentNode();
    if(DTM.NULL == currentNode)
      return 0;
    else
    {
      DTM dtm = xctxt.getDTM(currentNode);
      XMLString str = dtm.getStringValue(currentNode);
      return str.toDouble();
    }

  }
  else
    return m_arg0.execute(xctxt).num();
}
 

/**
 * The dyn:evaluate function evaluates a string as an XPath expression and returns
 * the resulting value, which might be a boolean, number, string, node set, result
 * tree fragment or external object. The sole argument is the string to be evaluated.
 * <p>
 * If the expression string passed as the second argument is an invalid XPath
 * expression (including an empty string), this function returns an empty node set.
 * <p>
 * You should only use this function if the expression must be constructed dynamically,
 * otherwise it is much more efficient to use the expression literally.
 *
 * @param myContext The ExpressionContext passed by the extension processor
 * @param xpathExpr The XPath expression string
 *
 * @return The evaluation result
 */
public static XObject evaluate(ExpressionContext myContext, String xpathExpr)
  throws SAXNotSupportedException
{
  if (myContext instanceof XPathContext.XPathExpressionContext)
  {
    XPathContext xctxt = null;
    try
    {
      xctxt = ((XPathContext.XPathExpressionContext) myContext).getXPathContext();
      XPath dynamicXPath = new XPath(xpathExpr, xctxt.getSAXLocator(),
                                     xctxt.getNamespaceContext(),
                                     XPath.SELECT);

      return dynamicXPath.execute(xctxt, myContext.getContextNode(),
                                  xctxt.getNamespaceContext());
    }
    catch (TransformerException e)
    {
      return new XNodeSet(xctxt.getDTMManager());
    }
  }
  else
    throw new SAXNotSupportedException(XSLMessages.createMessage(XSLTErrorResources.ER_INVALID_CONTEXT_PASSED, new Object[]{myContext })); //"Invalid context passed to evaluate "
}
 

/**
 * 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 which = getArg0AsNode(xctxt);

  if (DTM.NULL != which)
  {
    // Note that this is a different value than in previous releases
    // of Xalan. It's sensitive to the exact encoding of the node
    // handle anyway, so fighting to maintain backward compatability
    // really didn't make sense; it may change again as we continue
    // to experiment with balancing document and node numbers within
    // that value.
    return new XString("N" + Integer.toHexString(which).toUpperCase());
  }
  else
    return XString.EMPTYSTRING;
}
 

/**
 * Execute an expression in the XPath runtime context, and return the
 * result of the expression.
 *
 *
 * @param xctxt The XPath runtime context.
 * @param handler The target content handler.
 *
 * @return The result of the expression in the form of a <code>XObject</code>.
 *
 * @throws javax.xml.transform.TransformerException if a runtime exception
 *         occurs.
 * @throws org.xml.sax.SAXException
 */
public void executeCharsToContentHandler(
        XPathContext xctxt, org.xml.sax.ContentHandler handler)
          throws javax.xml.transform.TransformerException,
                 org.xml.sax.SAXException
{
  LocPathIterator clone = (LocPathIterator)m_clones.getInstance();

  int current = xctxt.getCurrentNode();
  clone.setRoot(current, xctxt);

  int node = clone.nextNode();
  DTM dtm = clone.getDTM(node);
  clone.detach();

  if(node != DTM.NULL)
  {
    dtm.dispatchCharactersEvents(node, handler, false);
  }
}
 

/**
 * Get the match score of the given node.
 *
 * @param xctxt The XPath runtime context.
 * @param context The node to be tested.
 *
 * @return {@link com.sun.org.apache.xpath.internal.patterns.NodeTest#SCORE_NODETEST},
 *         {@link com.sun.org.apache.xpath.internal.patterns.NodeTest#SCORE_NONE},
 *         {@link com.sun.org.apache.xpath.internal.patterns.NodeTest#SCORE_NSWILD},
 *         {@link com.sun.org.apache.xpath.internal.patterns.NodeTest#SCORE_QNAME}, or
 *         {@link com.sun.org.apache.xpath.internal.patterns.NodeTest#SCORE_OTHER}.
 *
 * @throws javax.xml.transform.TransformerException
 */
public double getMatchScore(XPathContext xctxt, int context)
        throws javax.xml.transform.TransformerException
{

  xctxt.pushCurrentNode(context);
  xctxt.pushCurrentExpressionNode(context);

  try
  {
    XObject score = execute(xctxt);

    return score.num();
  }
  finally
  {
    xctxt.popCurrentNode();
    xctxt.popCurrentExpressionNode();
  }

  // return XPath.MATCH_SCORE_NONE;
}
 

/**
 * 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
 * number.  If the argument is null, then get the number value from the
 * current context node.
 *
 * @param xctxt Runtime XPath context.
 *
 * @return The number value of the first argument, or the number 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 double getArg0AsNumber(XPathContext xctxt)
        throws javax.xml.transform.TransformerException
{

  if(null == m_arg0)
  {
    int currentNode = xctxt.getCurrentNode();
    if(DTM.NULL == currentNode)
      return 0;
    else
    {
      DTM dtm = xctxt.getDTM(currentNode);
      XMLString str = dtm.getStringValue(currentNode);
      return str.toDouble();
    }

  }
  else
    return m_arg0.execute(xctxt).num();
}
 

/**
 * 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();
}
 

/**
 * 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 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 which = getArg0AsNode(xctxt);

  if (DTM.NULL != which)
  {
    // Note that this is a different value than in previous releases
    // of Xalan. It's sensitive to the exact encoding of the node
    // handle anyway, so fighting to maintain backward compatability
    // really didn't make sense; it may change again as we continue
    // to experiment with balancing document and node numbers within
    // that value.
    return new XString("N" + Integer.toHexString(which).toUpperCase());
  }
  else
    return XString.EMPTYSTRING;
}
 

/**
 * 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;
}
 

/**
 * Test a node to see if it matches the given node test.
 *
 * @param xctxt XPath runtime context.
 *
 * @return {@link com.sun.org.apache.xpath.internal.patterns.NodeTest#SCORE_NODETEST},
 *         {@link com.sun.org.apache.xpath.internal.patterns.NodeTest#SCORE_NONE},
 *         {@link com.sun.org.apache.xpath.internal.patterns.NodeTest#SCORE_NSWILD},
 *         {@link com.sun.org.apache.xpath.internal.patterns.NodeTest#SCORE_QNAME}, or
 *         {@link com.sun.org.apache.xpath.internal.patterns.NodeTest#SCORE_OTHER}.
 *
 * @throws javax.xml.transform.TransformerException
 */
public XObject execute(XPathContext xctxt)
        throws javax.xml.transform.TransformerException
{

  int context = xctxt.getCurrentNode();
  DTMIterator nl = m_functionExpr.asIterator(xctxt, context);
  XNumber score = SCORE_NONE;

  if (null != nl)
  {
    int n;

    while (DTM.NULL != (n = nl.nextNode()))
    {
      score = (n == context) ? SCORE_OTHER : SCORE_NONE;

      if (score == SCORE_OTHER)
      {
        context = n;

        break;
      }
    }

    nl.detach();
  }

  return score;
}
 

/**
 * Test a node to see if it matches the given node test.
 *
 * @param xctxt XPath runtime context.
 *
 * @return {@link com.sun.org.apache.xpath.internal.patterns.NodeTest#SCORE_NODETEST},
 *         {@link com.sun.org.apache.xpath.internal.patterns.NodeTest#SCORE_NONE},
 *         {@link com.sun.org.apache.xpath.internal.patterns.NodeTest#SCORE_NSWILD},
 *         {@link com.sun.org.apache.xpath.internal.patterns.NodeTest#SCORE_QNAME}, or
 *         {@link com.sun.org.apache.xpath.internal.patterns.NodeTest#SCORE_OTHER}.
 *
 * @throws javax.xml.transform.TransformerException
 */
public XObject execute(XPathContext xctxt, int context)
        throws javax.xml.transform.TransformerException
{

  DTMIterator nl = m_functionExpr.asIterator(xctxt, context);
  XNumber score = SCORE_NONE;

  if (null != nl)
  {
    int n;

    while (DTM.NULL != (n = nl.nextNode()))
    {
      score = (n == context) ? SCORE_OTHER : SCORE_NONE;

      if (score == SCORE_OTHER)
      {
        context = n;

        break;
      }
    }

    // nl.detach();
  }
  nl.detach();

  return score;
}
 

/**
 * Cast object to type t.
 *
 * @param t Type of object to cast this to
 * @param support XPath context to use for the conversion
 *
 * @return This object as the given type t
 *
 * @throws javax.xml.transform.TransformerException
 */
public Object castToType(int t, XPathContext support)
        throws javax.xml.transform.TransformerException
{

  Object result;

  switch (t)
  {
  case CLASS_STRING :
    result = str();
    break;
  case CLASS_NUMBER :
    result = new Double(num());
    break;
  case CLASS_NODESET :
    result = iter();
    break;
  case CLASS_BOOLEAN :
    result = new Boolean(bool());
    break;
  case CLASS_UNKNOWN :
    result = m_obj;
    break;

  // %TBD%  What to do here?
  //    case CLASS_RTREEFRAG :
  //      result = rtree(support);
  //      break;
  default :
    error(XPATHErrorResources.ER_CANT_CONVERT_TO_TYPE,
          new Object[]{ getTypeString(),
                        Integer.toString(t) });  //"Can not convert "+getTypeString()+" to a type#"+t);

    result = null;
  }

  return result;
}
 

/**
 * Get the number of nodes in this node list.  The function is probably ill
 * named?
 *
 *
 * @param xctxt The XPath runtime context.
 *
 * @return the number of nodes in this node list.
 */
public int getLastPos(XPathContext xctxt)
{

  int count = 0;
  AxesWalker savedWalker = wi().getLastUsedWalker();

  try
  {
    ReverseAxesWalker clone = (ReverseAxesWalker) this.clone();

    clone.setRoot(this.getRoot());

    clone.setPredicateCount(this.getPredicateCount() - 1);

    clone.setPrevWalker(null);
    clone.setNextWalker(null);
    wi().setLastUsedWalker(clone);

    // Count 'em all
    // count = 1;
    int next;

    while (DTM.NULL != (next = clone.nextNode()))
    {
      count++;
    }
  }
  catch (CloneNotSupportedException cnse)
  {

    // can't happen
  }
  finally
  {
    wi().setLastUsedWalker(savedWalker);
  }

  return count;
}
 

/**
 * 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
{

  XMLString s1 = m_arg0.execute(xctxt).xstr();
  XMLString s2 = m_arg1.execute(xctxt).xstr();
  int index = s1.indexOf(s2);

  return (-1 == index)
         ? XString.EMPTYSTRING
         : (XString)s1.substring(index + s2.length());
}
 

/**
 * Execute a binary operation by calling execute on each of the operands,
 * and then calling the operate method on the derived class.
 *
 *
 * @param xctxt The runtime execution context.
 *
 * @return The XObject result of the operation.
 *
 * @throws javax.xml.transform.TransformerException
 */
public boolean bool(XPathContext xctxt)
        throws javax.xml.transform.TransformerException
{
  XObject left = m_left.execute(xctxt, true);
  XObject right = m_right.execute(xctxt, true);

  boolean result = left.equals(right) ? true : false;
      left.detach();
      right.detach();
  return result;
}
 

/**
 * 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 name = m_arg0.execute(xctxt).str();
  int context = xctxt.getCurrentNode();
  DTM dtm = xctxt.getDTM(context);
  int doc = dtm.getDocument();

  String uri = dtm.getUnparsedEntityURI(name);

  return new XString(uri);
}
 

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

  // Programmer's assert.  (And, no, I don't want the method to be abstract).
  System.out.println("Error! Function.execute should not be called!");

  return null;
}
 

/**
 * 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 name = m_arg0.execute(xctxt).str();
  int context = xctxt.getCurrentNode();
  DTM dtm = xctxt.getDTM(context);
  int doc = dtm.getDocument();

  String uri = dtm.getUnparsedEntityURI(name);

  return new XString(uri);
}
 

/**
 * Get the number of nodes in this node list.  The function is probably ill
 * named?
 *
 *
 * @param xctxt The XPath runtime context.
 *
 * @return the number of nodes in this node list.
 */
public int getLastPos(XPathContext xctxt)
{

  int count = 0;
  AxesWalker savedWalker = wi().getLastUsedWalker();

  try
  {
    ReverseAxesWalker clone = (ReverseAxesWalker) this.clone();

    clone.setRoot(this.getRoot());

    clone.setPredicateCount(this.getPredicateCount() - 1);

    clone.setPrevWalker(null);
    clone.setNextWalker(null);
    wi().setLastUsedWalker(clone);

    // Count 'em all
    // count = 1;
    int next;

    while (DTM.NULL != (next = clone.nextNode()))
    {
      count++;
    }
  }
  catch (CloneNotSupportedException cnse)
  {

    // can't happen
  }
  finally
  {
    wi().setLastUsedWalker(savedWalker);
  }

  return count;
}
 

/**
 *  Test whether a specified node is visible in the logical view of a
 * TreeWalker or NodeIterator. This function will be called by the
 * implementation of TreeWalker and NodeIterator; it is not intended to
 * be called directly from user code.
 * @param n  The node to check to see if it passes the filter or not.
 * @return  a constant to determine whether the node is accepted,
 *   rejected, or skipped, as defined  above .
 */
public short acceptNode(int n)
{

  XPathContext xctxt = m_lpi.getXPathContext();

  try
  {
    xctxt.pushCurrentNode(n);

    XObject score = execute(xctxt, n);

    // System.out.println("\n::acceptNode - score: "+score.num()+"::");
    if (score != NodeTest.SCORE_NONE)
    {
      if (getPredicateCount() > 0)
      {
        countProximityPosition(0);

        if (!executePredicates(n, xctxt))
          return DTMIterator.FILTER_SKIP;
      }

      return DTMIterator.FILTER_ACCEPT;
    }
  }
  catch (javax.xml.transform.TransformerException se)
  {

    // TODO: Fix this.
    throw new RuntimeException(se.getMessage());
  }
  finally
  {
    xctxt.popCurrentNode();
  }

  return DTMIterator.FILTER_SKIP;
}
 

/**
 * Execute a binary operation by calling execute on each of the operands,
 * and then calling the operate method on the derived class.
 *
 *
 * @param xctxt The runtime execution context.
 *
 * @return The XObject result of the operation.
 *
 * @throws javax.xml.transform.TransformerException
 */
public XObject execute(XPathContext xctxt)
        throws javax.xml.transform.TransformerException
{

  XObject left = m_left.execute(xctxt, true);
  XObject right = m_right.execute(xctxt, true);

  XObject result = operate(left, right);
  left.detach();
  right.detach();
  return result;
}
 

/**
 * Test a node to see if it matches the given node test.
 *
 * @param xctxt XPath runtime context.
 *
 * @return {@link com.sun.org.apache.xpath.internal.patterns.NodeTest#SCORE_NODETEST},
 *         {@link com.sun.org.apache.xpath.internal.patterns.NodeTest#SCORE_NONE},
 *         {@link com.sun.org.apache.xpath.internal.patterns.NodeTest#SCORE_NSWILD},
 *         {@link com.sun.org.apache.xpath.internal.patterns.NodeTest#SCORE_QNAME}, or
 *         {@link com.sun.org.apache.xpath.internal.patterns.NodeTest#SCORE_OTHER}.
 *
 * @throws javax.xml.transform.TransformerException
 */
public XObject execute(XPathContext xctxt)
        throws javax.xml.transform.TransformerException
{

  int context = xctxt.getCurrentNode();
  DTMIterator nl = m_functionExpr.asIterator(xctxt, context);
  XNumber score = SCORE_NONE;

  if (null != nl)
  {
    int n;

    while (DTM.NULL != (n = nl.nextNode()))
    {
      score = (n == context) ? SCORE_OTHER : SCORE_NONE;

      if (score == SCORE_OTHER)
      {
        context = n;

        break;
      }
    }

    nl.detach();
  }

  return score;
}
 

/**
 * 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 s1 = m_arg0.execute(xctxt).str();
  String s2 = m_arg1.execute(xctxt).str();
  int index = s1.indexOf(s2);

  return (-1 == index)
         ? XString.EMPTYSTRING : new XString(s1.substring(0, index));
}
 

/**
 *  Test whether a specified node is visible in the logical view of a
 * TreeWalker or NodeIterator. This function will be called by the
 * implementation of TreeWalker and NodeIterator; it is not intended to
 * be called directly from user code.
 * @param n  The node to check to see if it passes the filter or not.
 * @return  a constant to determine whether the node is accepted,
 *   rejected, or skipped, as defined  above .
 */
public short acceptNode(int n)
{

  XPathContext xctxt = m_lpi.getXPathContext();

  try
  {
    xctxt.pushCurrentNode(n);

    XObject score = execute(xctxt, n);

    // System.out.println("\n::acceptNode - score: "+score.num()+"::");
    if (score != NodeTest.SCORE_NONE)
    {
      if (getPredicateCount() > 0)
      {
        countProximityPosition(0);

        if (!executePredicates(n, xctxt))
          return DTMIterator.FILTER_SKIP;
      }

      return DTMIterator.FILTER_ACCEPT;
    }
  }
  catch (javax.xml.transform.TransformerException se)
  {

    // TODO: Fix this.
    throw new RuntimeException(se.getMessage());
  }
  finally
  {
    xctxt.popCurrentNode();
  }

  return DTMIterator.FILTER_SKIP;
}
 

/**
 * AND two expressions and return the boolean result. Override
 * superclass method for optimization purposes.
 *
 * @param xctxt The runtime execution context.
 *
 * @return {@link com.sun.org.apache.xpath.internal.objects.XBoolean#S_TRUE} or
 * {@link com.sun.org.apache.xpath.internal.objects.XBoolean#S_FALSE}.
 *
 * @throws javax.xml.transform.TransformerException
 */
public XObject execute(XPathContext xctxt) throws javax.xml.transform.TransformerException
{

  XObject expr1 = m_left.execute(xctxt);

  if (expr1.bool())
  {
    XObject expr2 = m_right.execute(xctxt);

    return expr2.bool() ? XBoolean.S_TRUE : XBoolean.S_FALSE;
  }
  else
    return XBoolean.S_FALSE;
}