1 /* 2 * reserved comment block 3 * DO NOT REMOVE OR ALTER! 4 */ 5 /* 6 * Licensed to the Apache Software Foundation (ASF) under one or more 7 * contributor license agreements. See the NOTICE file distributed with 8 * this work for additional information regarding copyright ownership. 9 * The ASF licenses this file to You under the Apache License, Version 2.0 10 * (the "License"); you may not use this file except in compliance with 11 * the License. You may obtain a copy of the License at 12 * 13 * http://www.apache.org/licenses/LICENSE-2.0 14 * 15 * Unless required by applicable law or agreed to in writing, software 16 * distributed under the License is distributed on an "AS IS" BASIS, 17 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 18 * See the License for the specific language governing permissions and 19 * limitations under the License. 20 */ 21 22 package com.sun.org.apache.xalan.internal.xsltc.dom; 23 24 import com.sun.org.apache.xalan.internal.xsltc.DOM; 25 import com.sun.org.apache.xalan.internal.xsltc.runtime.BasisLibrary; 26 import com.sun.org.apache.xml.internal.dtm.DTMAxisIterator; 27 import com.sun.org.apache.xml.internal.dtm.ref.DTMAxisIteratorBase; 28 29 /** 30 * UnionIterator takes a set of NodeIterators and produces 31 * a merged NodeSet in document order with duplicates removed 32 * The individual iterators are supposed to generate nodes 33 * in document order 34 * @author Jacek Ambroziak 35 * @author Santiago Pericas-Geertsen 36 */ 37 public final class UnionIterator extends MultiValuedNodeHeapIterator { 38 /** wrapper for NodeIterators to support iterator 39 comparison on the value of their next() method 40 */ 41 final private DOM _dom; 42 43 private final class LookAheadIterator 44 extends MultiValuedNodeHeapIterator.HeapNode 45 { 46 public DTMAxisIterator iterator; 47 LookAheadIterator(DTMAxisIterator iterator)48 public LookAheadIterator(DTMAxisIterator iterator) { 49 super(); 50 this.iterator = iterator; 51 } 52 step()53 public int step() { 54 _node = iterator.next(); 55 return _node; 56 } 57 cloneHeapNode()58 public HeapNode cloneHeapNode() { 59 LookAheadIterator clone = (LookAheadIterator) super.cloneHeapNode(); 60 clone.iterator = iterator.cloneIterator(); 61 return clone; 62 } 63 setMark()64 public void setMark() { 65 super.setMark(); 66 iterator.setMark(); 67 } 68 gotoMark()69 public void gotoMark() { 70 super.gotoMark(); 71 iterator.gotoMark(); 72 } 73 isLessThan(HeapNode heapNode)74 public boolean isLessThan(HeapNode heapNode) { 75 LookAheadIterator comparand = (LookAheadIterator) heapNode; 76 return _dom.lessThan(_node, heapNode._node); 77 } 78 setStartNode(int node)79 public HeapNode setStartNode(int node) { 80 iterator.setStartNode(node); 81 return this; 82 } 83 reset()84 public HeapNode reset() { 85 iterator.reset(); 86 return this; 87 } 88 } // end of LookAheadIterator 89 UnionIterator(DOM dom)90 public UnionIterator(DOM dom) { 91 _dom = dom; 92 } 93 addIterator(DTMAxisIterator iterator)94 public UnionIterator addIterator(DTMAxisIterator iterator) { 95 addHeapNode(new LookAheadIterator(iterator)); 96 return this; 97 } 98 } 99