/*
* 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: DTMChildIterNodeList.java 468653 2006-10-28 07:07:05Z minchau $
*/
package org.apache.xml.dtm.ref;
import org.apache.xml.dtm.DTM;
import org.w3c.dom.Node;
/**
* DTMNodeList
gives us an implementation of the DOM's
* NodeList interface wrapped around a DTM Iterator. The author
* considers this something of an abominations, since NodeList was not
* intended to be a general purpose "list of nodes" API and is
* generally considered by the DOM WG to have be a mistake... but I'm
* told that some of the XPath/XSLT folks say they must have this
* solution.
*
* Please note that this is not necessarily equivlaent to a DOM
* NodeList operating over the same document. In particular:
*
State: In progress!!
* */ public class DTMChildIterNodeList extends DTMNodeListBase { private int m_firstChild; private DTM m_parentDTM; //================================================================ // Methods unique to this class private DTMChildIterNodeList() { } /** * Public constructor: Create a NodeList to support * DTMNodeProxy.getChildren(). * * Unfortunately AxisIterators and DTMIterators don't share an API, * so I can't use the existing Axis.CHILD iterator. Rather than * create Yet Another Class, let's set up a special case of this * one. * * @param parentDTM The DTM containing this node * @param parentHandle DTM node-handle integer * */ public DTMChildIterNodeList(DTM parentDTM,int parentHandle) { m_parentDTM=parentDTM; m_firstChild=parentDTM.getFirstChild(parentHandle); } //================================================================ // org.w3c.dom.NodeList API follows /** * Returns theindex
th item in the collection. If
* index
is greater than or equal to the number of nodes in
* the list, this returns null
.
* @param index Index into the collection.
* @return The node at the index
th position in the
* NodeList
, or null
if that is not a valid
* index.
*/
public Node item(int index) {
int handle=m_firstChild;
while(--index>=0 && handle!=DTM.NULL) {
handle=m_parentDTM.getNextSibling(handle);
}
if (handle == DTM.NULL) {
return null;
}
return m_parentDTM.getNode(handle);
}
/**
* The number of nodes in the list. The range of valid child node indices
* is 0 to length-1
inclusive.
*/
public int getLength() {
int count=0;
for (int handle=m_firstChild;
handle!=DTM.NULL;
handle=m_parentDTM.getNextSibling(handle)) {
++count;
}
return count;
}
}