/*
* The Apache Software License, Version 1.1
*
*
* Copyright (c) 1999 The Apache Software Foundation. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution,
* if any, must include the following acknowledgment:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowledgment may appear in the software itself,
* if and wherever such third-party acknowledgments normally appear.
*
* 4. The names "Xalan" and "Apache Software Foundation" must
* not be used to endorse or promote products derived from this
* software without prior written permission. For written
* permission, please contact apache@apache.org.
*
* 5. Products derived from this software may not be called "Apache",
* nor may "Apache" appear in their name, without prior written
* permission of the Apache Software Foundation.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation and was
* originally based on software copyright (c) 1999, Lotus
* Development Corporation., http://www.lotus.com. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*/
package org.apache.xalan.transformer;
import java.util.Vector;
import org.apache.xpath.axes.LocPathIterator;
import org.apache.xml.utils.QName;
import org.apache.xml.utils.XMLString;
import org.apache.xalan.templates.KeyDeclaration;
import org.apache.xpath.NodeSetDTM;
//import org.w3c.dom.Node;
//import org.w3c.dom.DOMException;
//import org.w3c.dom.traversal.NodeIterator;
import org.apache.xml.dtm.DTM;
import org.apache.xml.dtm.DTMIterator;
/**
* <meta name="usage" content="internal"/>
* This class implements an optimized iterator for
* "key()" patterns. It uses a KeyIterator to walk the
* source tree and incrementally build a list of nodes that match
* a given key name, match pattern and value.
*/
public class KeyRefIterator extends LocPathIterator
{
/** Key name.
* @serial */
private final QName m_name;
/** Use field of key function.
* @serial */
private final XMLString m_lookupKey;
/** Main Key iterator for this iterator.
* @serial */
private final KeyIterator m_ki;
/**
* Get key name
*
*
* @return Key name
*/
public QName getName()
{
return m_name;
}
/**
* Constructor KeyRefIterator
*
*
* @param ref Key value to match
* @param ki The main key iterator used to walk the source tree
*/
public KeyRefIterator(XMLString ref, KeyIterator ki)
{
super(ki.getPrefixResolver());
m_ki = ki;
m_name = ki.getName();
m_lookupKey = ref;
this.m_execContext = ki.getXPathContext();
setShouldCacheNodes(true);
}
/**
* 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 the cache is on, and the node has already been found, then
// just return from the list.
NodeSetDTM m_cachedNodes = getCachedNodes();
// We are not using the NodeSetDTM methods getCurrentPos() and nextNode()
// in this case because the nodeset is not cloned and therefore
// the positions it indicates may not be associated with the
// current iterator.
if ((null != m_cachedNodes)
&& (m_next < m_cachedNodes.size()))
{
int next = m_cachedNodes.elementAt(m_next);
this.setCurrentPos(++m_next);
m_lastFetched = next;
return next;
}
if (m_foundLast)
{
m_lastFetched = DTM.NULL;
return DTM.NULL;
}
int next = DTM.NULL;
if ( m_ki.getLookForMoreNodes())
{
((KeyWalker)m_ki.getFirstWalker()).m_lookupKey = m_lookupKey;
next = m_ki.nextNode();
}
if (DTM.NULL != next)
{
m_lastFetched = next;
this.setCurrentPos(++m_next);
return next;
}
else
m_foundLast = true;
m_lastFetched = DTM.NULL;
return DTM.NULL;
}
/**
* Get a cloned LocPathIterator that holds the same
* position as this iterator.
*
* @return A clone of this iterator that holds the same node position.
*
* @throws CloneNotSupportedException
*/
public Object clone() throws CloneNotSupportedException
{
// I wonder if we really want to clone the second time. Myriam review.
KeyRefIterator clone = (KeyRefIterator)super.clone();
// clone.m_ki = (KeyIterator)m_ki.clone();
return clone;
}
// /**
// * Get a cloned Iterator that is reset to the beginning
// * of the query.
// *
// * @return A cloned NodeIterator set of the start of the query.
// *
// * @throws CloneNotSupportedException
// */
// public NodeIterator cloneWithReset() throws CloneNotSupportedException
// {
// KeyRefIterator clone = (KeyRefIterator)super.cloneWithReset();
//
// return clone;
// }
/**
* Reset the iterator.
*/
public void reset()
{
super.reset();
// setShouldCacheNodes(true);
setCurrentPos(0);
}
/**
* Detaches the iterator from the set which it iterated over, releasing
* any computational resources and placing the iterator in the INVALID
* state. After<code>detach</code> has been invoked, calls to
* <code>nextNode</code> or<code>previousNode</code> will raise the
* exception INVALID_STATE_ERR.
*/
public void detach()
{
// I don't think we want to detach at all for this iterator.
// Myriam needs to review. -sb.
}
/**
* Add a node matching this ref to the cached nodes for this iterator
*
*
* @param node Node to add to cached nodes
*/
public void addNode(int node)
{
NodeSetDTM m_cachedNodes = getCachedNodes();
if (null != m_cachedNodes)
{
if(!m_cachedNodes.contains(node))
m_cachedNodes.addElement(node);
}
}
}