/*

 * 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.

 */

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

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

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

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

/**

 * This class implements an optimized iterator for

 * "." patterns, that is, the self axes without any predicates.

 * @see com.sun.org.apache.xpath.internal.axes.LocPathIterator

 * @xsl.usage advanced

 */

public class SelfIteratorNoPredicate extends LocPathIterator

{

    static final long serialVersionUID = -4226887905279814201L;

  /**

   * Create a SelfIteratorNoPredicate 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.

   *

   * @throws javax.xml.transform.TransformerException

   */

  SelfIteratorNoPredicate(Compiler compiler, int opPos, int analysis)

          throws javax.xml.transform.TransformerException

  {

    super(compiler, opPos, analysis, false);

  }

  /**

   * Create a SelfIteratorNoPredicate object.

   *

   * @throws javax.xml.transform.TransformerException

   */

  public SelfIteratorNoPredicate()

          throws javax.xml.transform.TransformerException

  {

    super(null);

  }

  /**

   *  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;

    DTM dtm = m_cdtm;

    m_lastFetched = next = (DTM.NULL == m_lastFetched)

                           ? m_context

                           : DTM.NULL;

    // m_lastFetched = next;

    if (DTM.NULL != next)

    {

      m_pos++;

      return next;

    }

    else

    {

      m_foundLast = true;

      return DTM.NULL;

    }

  }

  /**

   * Return the first node out of the nodeset, if this expression is

   * a nodeset expression.  This is the default implementation for

   * nodesets.  Derived classes should try and override this and return a

   * value without having to do a clone operation.

   * @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

  {

    return xctxt.getCurrentNode();

  }

  /**

   * Get the index of the last node that can be itterated to.

   * This probably will need to be overridded by derived classes.

   *

   * @param xctxt XPath runtime context.

   *

   * @return the index of the last node that can be itterated to.

   */

  public int getLastPos(XPathContext xctxt)

  {

    return 1;

  }

}