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.axes;
  
  import org.apache.xml.dtm.DTM;
  import org.apache.xml.dtm.DTMFilter;
  import org.apache.xpath.XPathContext;
  import org.apache.xpath.compiler.Compiler;
  
  /**
   * This class implements an optimized iterator for
   * "node()" patterns, that is, any children of the
   * context node.
   * @see org.apache.xpath.axes.LocPathIterator
   * @xsl.usage advanced
   */
  public class ChildIterator extends LocPathIterator
  {
      static final long serialVersionUID = -6935428015142993583L;
  
    /**
     * Create a ChildIterator object.
     *
     * @param compiler A reference to the Compiler that contains the op map.
     * @param opPos The position within the op map, which contains the
     * location path expression for this itterator.
     * @param analysis Analysis bits of the entire pattern.
     *
     * @throws javax.xml.transform.TransformerException
     */
    ChildIterator(Compiler compiler, int opPos, int analysis)
            throws javax.xml.transform.TransformerException
    {
      super(compiler, opPos, analysis, false);
  
      // This iterator matches all kinds of nodes
      initNodeTest(DTMFilter.SHOW_ALL);
    }
    
    /**
     * Return the first node out of the nodeset, if this expression is 
     * a nodeset expression.  This is the default implementation for 
     * nodesets.
     * <p>WARNING: Do not mutate this class from this function!</p>
     * @param xctxt The XPath runtime context.
     * @return the first node out of the nodeset, or DTM.NULL.
     */
    public int asNode(XPathContext xctxt)
      throws javax.xml.transform.TransformerException
    {
      int current = xctxt.getCurrentNode();
      
      DTM dtm = xctxt.getDTM(current);
      
      return dtm.getFirstChild(current);
    }
  
    /**
     *  Returns the next node in the set and advances the position of the
     * iterator in the set. After a NodeIterator is created, the first call
     * to nextNode() returns the first node in the set.
     *
     * @return  The next <code>Node</code> in the set being iterated over, or
     *   <code>null</code> if there are no more members in that set.
     */
    public int nextNode()
    {
    	if(m_foundLast)
    		return DTM.NULL;
  
      int next;
  
      m_lastFetched = next = (DTM.NULL == m_lastFetched)
                             ? m_cdtm.getFirstChild(m_context)
                             : m_cdtm.getNextSibling(m_lastFetched);
  
      // m_lastFetched = next;
      if (DTM.NULL != next)
      {
        m_pos++;
        return next;
      }
      else
      {
        m_foundLast = true;
  
        return DTM.NULL;
      }
    }
    
    /**
     * Returns the axis being iterated, if it is known.
     * 
     * @return Axis.CHILD, etc., or -1 if the axis is not known or is of multiple 
     * types.
     */
    public int getAxis()
    {
      return org.apache.xml.dtm.Axis.CHILD;
    }
  
  
  }
  