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 * reserved comment block

 * DO NOT REMOVE OR ALTER!

 */

/*

 * 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.

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package com.sun.org.apache.xpath.internal.axes;

import com.sun.org.apache.xml.internal.dtm.DTM;

import com.sun.org.apache.xml.internal.dtm.DTMFilter;

import com.sun.org.apache.xpath.internal.XPathContext;

import com.sun.org.apache.xpath.internal.compiler.Compiler;

/**

 * This class implements an optimized iterator for

 * "node()" patterns, that is, any children of the

 * context node.

 * @see com.sun.org.apache.xpath.internal.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 com.sun.org.apache.xml.internal.dtm.Axis.CHILD;

  }

}