code: /*
   * 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.
   */
  /*
   * $Id$
   */
  package org.apache.xpath.patterns;
  
  import org.apache.xml.dtm.DTM;
  import org.apache.xml.dtm.DTMIterator;
  import org.apache.xpath.Expression;
  import org.apache.xpath.ExpressionOwner;
  import org.apache.xpath.XPathContext;
  import org.apache.xpath.XPathVisitor;
  import org.apache.xpath.objects.XNumber;
  import org.apache.xpath.objects.XObject;
  
  /**
   * Match pattern step that contains a function.
   * @xsl.usage advanced
   */
  public class FunctionPattern extends StepPattern
  {
      static final long serialVersionUID = -5426793413091209944L;
  
    /**
     * Construct a FunctionPattern from a
     * {@link org.apache.xpath.functions.Function expression}.
     *
     * NEEDSDOC @param expr
     */
    public FunctionPattern(Expression expr, int axis, int predaxis)
    {
  
      super(0, null, null, axis, predaxis);
  
      m_functionExpr = expr;
    }
  
    /**
     * Static calc of match score.
     */
    public final void calcScore()
    {
  
      m_score = SCORE_OTHER;
  
      if (null == m_targetString)
        calcTargetString();
    }
  
    /**
     * Should be a {@link org.apache.xpath.functions.Function expression}.
     *  @serial   
     */
    Expression m_functionExpr;
    
    /**
     * 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)
    {
      super.fixupVariables(vars, globalsSize);
      m_functionExpr.fixupVariables(vars, globalsSize);
    }
  
    
    /**
     * Test a node to see if it matches the given node test.
     *
     * @param xctxt XPath runtime context.
     *
     * @return {@link org.apache.xpath.patterns.NodeTest#SCORE_NODETEST},
     *         {@link org.apache.xpath.patterns.NodeTest#SCORE_NONE},
     *         {@link org.apache.xpath.patterns.NodeTest#SCORE_NSWILD},
     *         {@link org.apache.xpath.patterns.NodeTest#SCORE_QNAME}, or
     *         {@link org.apache.xpath.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;
    }
    
    /**
     * Test a node to see if it matches the given node test.
     *
     * @param xctxt XPath runtime context.
     *
     * @return {@link org.apache.xpath.patterns.NodeTest#SCORE_NODETEST},
     *         {@link org.apache.xpath.patterns.NodeTest#SCORE_NONE},
     *         {@link org.apache.xpath.patterns.NodeTest#SCORE_NSWILD},
     *         {@link org.apache.xpath.patterns.NodeTest#SCORE_QNAME}, or
     *         {@link org.apache.xpath.patterns.NodeTest#SCORE_OTHER}.
     *
     * @throws javax.xml.transform.TransformerException
     */
    public XObject execute(XPathContext xctxt, int context, 
                           DTM dtm, int expType)
            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();
      }
  
      return score;
    }
    
    /**
     * Test a node to see if it matches the given node test.
     *
     * @param xctxt XPath runtime context.
     *
     * @return {@link org.apache.xpath.patterns.NodeTest#SCORE_NODETEST},
     *         {@link org.apache.xpath.patterns.NodeTest#SCORE_NONE},
     *         {@link org.apache.xpath.patterns.NodeTest#SCORE_NSWILD},
     *         {@link org.apache.xpath.patterns.NodeTest#SCORE_QNAME}, or
     *         {@link org.apache.xpath.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;
    }
    
    class FunctionOwner implements ExpressionOwner
    {
      /**
       * @see ExpressionOwner#getExpression()
       */
      public Expression getExpression()
      {
        return m_functionExpr;
      }
  
  
      /**
       * @see ExpressionOwner#setExpression(Expression)
       */
      public void setExpression(Expression exp)
      {
      	exp.exprSetParent(FunctionPattern.this);
      	m_functionExpr = exp;
      }
    }
    
    /**
     * Call the visitor for the function.
     */
    protected void callSubtreeVisitors(XPathVisitor visitor)
    {
      m_functionExpr.callVisitors(new FunctionOwner(), visitor);
      super.callSubtreeVisitors(visitor);
    }
  
  }
  