1 /*
   2  * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package com.sun.org.apache.xpath.internal.jaxp;
  27 
  28 import java.util.Iterator;
  29 import javax.xml.xpath.XPathException;
  30 import javax.xml.xpath.XPathNodes;
  31 import javax.xml.xpath.XPathEvaluationResult.XPathResultType;
  32 import org.w3c.dom.Node;
  33 import org.w3c.dom.NodeList;
  34 
  35 /**
  36  * This class implements XPathNodes that represents a set of nodes selected by 
  37  * evaluating an expression.
  38  */
  39 public class XPathNodesImpl implements XPathNodes {
  40     XPathResultType type;
  41     Class<Node> elementType;
  42     NodeList nodeList = null;
  43 
  44     public XPathNodesImpl(NodeList nodeList, XPathResultType type, Class<Node> elementType) {
  45         this.nodeList = nodeList;
  46         this.type = type;
  47         this.elementType = elementType;
  48     }
  49     
  50     @Override
  51     public Iterator<Node> iterator() {
  52         return new NodeSetIterator<>(elementType);
  53     }
  54 
  55 
  56     class NodeSetIterator<E> implements Iterator<E> {
  57         int currentIndex;
  58         Class<E> elementType;
  59         NodeSetIterator(Class<E> elementType) {
  60             this.elementType = elementType;
  61         }
  62         public boolean hasNext() {
  63             if (type != XPathResultType.NODE) {
  64                 throw new UnsupportedOperationException("Incorrect type: result"
  65                         + "type requested: " + type + ", but assumed"
  66                         + "Node.");
  67             }
  68             if (nodeList != null) {
  69                 return currentIndex < nodeList.getLength();
  70             }
  71 
  72             return false;
  73         }
  74 
  75         public E next() {
  76             if (nodeList != null && nodeList.getLength() > 0) {
  77                 return elementType.cast(nodeList.item(currentIndex++));
  78             }
  79             return null;
  80         }
  81     }
  82 
  83     @Override
  84     public int size() {
  85         if (nodeList != null) {
  86             return nodeList.getLength();
  87         }
  88         return 0;
  89     }
  90 
  91     @Override
  92     public Node get(int index) throws XPathException {
  93         if (index <0 || index >= size()) {
  94             throw new IndexOutOfBoundsException("Index " + index + " is out of bounds");
  95         }
  96         if (nodeList != null) {
  97             return (Node)nodeList.item(index);
  98         }
  99         return null;
 100     }
 101 }