src/org/apache/xpath/axes/AncestorOrSelfWalker.java

/*
 * The Apache Software License, Version 1.1
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 * This software consists of voluntary contributions made by many
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 * originally based on software copyright (c) 1999, Lotus
 * Development Corporation., http://www.lotus.com.  For more
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package org.apache.xpath.axes;

import java.util.Stack;

import org.apache.xpath.axes.LocPathIterator;
import org.apache.xpath.XPath;
import org.apache.xpath.XPathContext;
import org.apache.xpath.DOMHelper;

import org.w3c.dom.Node;

/**
 * Walker for the 'ancestor-or-self' axes.
 * @see <a href="http://www.w3.org/TR/xpath#axes">XPath axes descriptions</a>
 */
public class AncestorOrSelfWalker extends AncestorWalker
{

  /**
   * Construct an AncestorOrSelfWalker using a LocPathWalker.
   *
   * @param locPathIterator The location path iterator that 'owns' this walker.
   */
  public AncestorOrSelfWalker(LocPathIterator locPathIterator)
  {
    super(locPathIterator);
  }

  /**
   * Push the ancestor nodes.
   *
   * @param n The context node.
   */
  protected void pushAncestors(Node n)
  {

    m_ancestors = new Stack();

    m_ancestors.push(n);

    DOMHelper dh = m_lpi.getDOMHelper();

    while (null != (n = dh.getParentOfNode(n)))
    {
      m_ancestors.push(n);
    }

    m_nextLevelAmount = m_ancestors.isEmpty() ? 0 : 1;
    m_ancestorsPos = m_ancestors.size() - 1;
  }

  /**
   * Tell what's the maximum level this axes can descend to.
   *
   * @return An estimation of the maximum level this axes can descend to.
   */
  protected int getLevelMax()
  {
    return m_lpi.getDOMHelper().getLevel(m_root);
  }
}