001    /*
002     * Licensed to the Apache Software Foundation (ASF) under one
003     * or more contributor license agreements. See the NOTICE file
004     * distributed with this work for additional information
005     * regarding copyright ownership. The ASF licenses this file
006     * to you under the Apache License, Version 2.0 (the  "License");
007     * you may not use this file except in compliance with the License.
008     * You may obtain a copy of the License at
009     *
010     *     http://www.apache.org/licenses/LICENSE-2.0
011     *
012     * Unless required by applicable law or agreed to in writing, software
013     * distributed under the License is distributed on an "AS IS" BASIS,
014     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015     * See the License for the specific language governing permissions and
016     * limitations under the License.
017     */
018    /*
019     * $Id: DTMNodeListBase.java 468653 2006-10-28 07:07:05Z minchau $
020     */
021    package org.apache.xml.dtm.ref;
022    import org.w3c.dom.Node;
023    
024    /**
025     * <code>DTMNodeList</code> gives us an implementation of the DOM's
026     * NodeList interface wrapped around a DTM Iterator. The author
027     * considers this something of an abominations, since NodeList was not
028     * intended to be a general purpose "list of nodes" API and is
029     * generally considered by the DOM WG to have be a mistake... but I'm
030     * told that some of the XPath/XSLT folks say they must have this
031     * solution.
032     *
033     * Please note that this is not necessarily equivlaent to a DOM
034     * NodeList operating over the same document. In particular:
035     * <ul>
036     *
037     * <li>If there are several Text nodes in logical succession (ie,
038     * across CDATASection and EntityReference boundaries), we will return
039     * only the first; the caller is responsible for stepping through
040     * them.
041     * (%REVIEW% Provide a convenience routine here to assist, pending
042     * proposed DOM Level 3 getAdjacentText() operation?) </li>
043     *
044     * <li>Since the whole XPath/XSLT architecture assumes that the source
045     * document is not altered while we're working with it, we do not
046     * promise to implement the DOM NodeList's "live view" response to
047     * document mutation. </li>
048     *
049     * </ul>
050     *
051     * <p>State: In progress!!</p>
052     *
053     */
054    public class DTMNodeListBase implements org.w3c.dom.NodeList {
055        public DTMNodeListBase() {
056        }
057    
058        //================================================================
059        // org.w3c.dom.NodeList API follows
060    
061        /**
062         * Returns the <code>index</code>th item in the collection. If 
063         * <code>index</code> is greater than or equal to the number of nodes in 
064         * the list, this returns <code>null</code>.
065         * @param index Index into the collection.
066         * @return The node at the <code>index</code>th position in the 
067         *   <code>NodeList</code>, or <code>null</code> if that is not a valid 
068         *   index.
069         */
070        public Node item(int index) {
071            return null;
072        }
073    
074        /**
075         * The number of nodes in the list. The range of valid child node indices 
076         * is 0 to <code>length-1</code> inclusive. 
077         */
078        public int getLength() {
079            return 0;
080        }
081    }