| /* |
| * 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. |
| */ |
| /* |
| * $Id$ |
| */ |
| |
| package org.apache.xalan.xsltc.dom; |
| |
| import org.apache.xalan.xsltc.runtime.BasisLibrary; |
| import org.apache.xml.dtm.DTMAxisIterator; |
| import org.apache.xml.dtm.ref.DTMAxisIteratorBase; |
| |
| /** |
| * A step iterator is used to evaluate expressions like "BOOK/TITLE". |
| * A better name for this iterator would have been ParentIterator since |
| * both "BOOK" and "TITLE" are steps in XPath lingo. Step iterators are |
| * constructed from two other iterators which we are going to refer to |
| * as "outer" and "inner". Every node from the outer iterator (the one |
| * for BOOK in our example) is used to initialize the inner iterator. |
| * After this initialization, every node from the inner iterator is |
| * returned (in essence, implementing a "nested loop"). |
| * @author Jacek Ambroziak |
| * @author Santiago Pericas-Geertsen |
| * @author Erwin Bolwidt <ejb@klomp.org> |
| * @author Morten Jorgensen |
| */ |
| public class StepIterator extends DTMAxisIteratorBase { |
| |
| /** |
| * A reference to the "outer" iterator. |
| */ |
| protected DTMAxisIterator _source; |
| |
| /** |
| * A reference to the "inner" iterator. |
| */ |
| protected DTMAxisIterator _iterator; |
| |
| /** |
| * Temp variable to store a marked position. |
| */ |
| private int _pos = -1; |
| |
| public StepIterator(DTMAxisIterator source, DTMAxisIterator iterator) { |
| _source = source; |
| _iterator = iterator; |
| // System.out.println("SI source = " + source + " this = " + this); |
| // System.out.println("SI iterator = " + iterator + " this = " + this); |
| } |
| |
| |
| public void setRestartable(boolean isRestartable) { |
| _isRestartable = isRestartable; |
| _source.setRestartable(isRestartable); |
| _iterator.setRestartable(true); // must be restartable |
| } |
| |
| public DTMAxisIterator cloneIterator() { |
| _isRestartable = false; |
| try { |
| final StepIterator clone = (StepIterator) super.clone(); |
| clone._source = _source.cloneIterator(); |
| clone._iterator = _iterator.cloneIterator(); |
| clone._iterator.setRestartable(true); // must be restartable |
| clone._isRestartable = false; |
| return clone.reset(); |
| } |
| catch (CloneNotSupportedException e) { |
| BasisLibrary.runTimeError(BasisLibrary.ITERATOR_CLONE_ERR, |
| e.toString()); |
| return null; |
| } |
| } |
| |
| public DTMAxisIterator setStartNode(int node) { |
| if (_isRestartable) { |
| // Set start node for left-hand iterator... |
| _source.setStartNode(_startNode = node); |
| |
| // ... and get start node for right-hand iterator from left-hand, |
| // with special case for //* path - see ParentLocationPath |
| _iterator.setStartNode(_includeSelf ? _startNode : _source.next()); |
| return resetPosition(); |
| } |
| return this; |
| } |
| |
| public DTMAxisIterator reset() { |
| _source.reset(); |
| // Special case for //* path - see ParentLocationPath |
| _iterator.setStartNode(_includeSelf ? _startNode : _source.next()); |
| return resetPosition(); |
| } |
| |
| public int next() { |
| for (int node;;) { |
| // Try to get another node from the right-hand iterator |
| if ((node = _iterator.next()) != END) { |
| return returnNode(node); |
| } |
| // If not, get the next starting point from left-hand iterator... |
| else if ((node = _source.next()) == END) { |
| return END; |
| } |
| // ...and pass it on to the right-hand iterator |
| else { |
| _iterator.setStartNode(node); |
| } |
| } |
| } |
| |
| public void setMark() { |
| _source.setMark(); |
| _iterator.setMark(); |
| //_pos = _position; |
| } |
| |
| public void gotoMark() { |
| _source.gotoMark(); |
| _iterator.gotoMark(); |
| //_position = _pos; |
| } |
| } |