| /* |
| * 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: DOMDeepNodeListImpl.cpp 568078 2007-08-21 11:43:25Z amassari $ |
| */ |
| |
| #include "DOMDeepNodeListImpl.hpp" |
| #include "DOMElementImpl.hpp" |
| #include "DOMDocumentImpl.hpp" |
| #include "DOMCasts.hpp" |
| #include "DOMNodeImpl.hpp" |
| #include <xercesc/util/XMLUniDefs.hpp> |
| #include <limits.h> |
| |
| XERCES_CPP_NAMESPACE_BEGIN |
| |
| |
| static const XMLCh kAstr[] = {chAsterisk, chNull}; |
| |
| DOMDeepNodeListImpl::DOMDeepNodeListImpl(const DOMNode *rootNode, |
| const XMLCh *tagName) |
| : fRootNode(rootNode) |
| , fChanges(0) |
| , fCurrentNode(0) |
| , fCurrentIndexPlus1(0) |
| , fNamespaceURI(0) |
| , fMatchAllURI(false) |
| , fMatchURIandTagname(false) |
| { |
| fTagName = ((DOMDocumentImpl *)(castToNodeImpl(rootNode)->getOwnerDocument()))->getPooledString(tagName); |
| fMatchAll = XMLString::equals(fTagName, kAstr); |
| } |
| |
| |
| //DOM Level 2 |
| DOMDeepNodeListImpl::DOMDeepNodeListImpl(const DOMNode *rootNode, |
| const XMLCh *namespaceURI, |
| const XMLCh *localName) |
| : fRootNode(rootNode) |
| , fChanges(0) |
| , fCurrentNode(0) |
| , fCurrentIndexPlus1(0) |
| , fMatchAllURI(false) |
| , fMatchURIandTagname(true) |
| { |
| fTagName = ((DOMDocumentImpl *)(castToNodeImpl(rootNode)->getOwnerDocument()))->getPooledString(localName); |
| fMatchAll = XMLString::equals(fTagName, kAstr); |
| fMatchAllURI = XMLString::equals(namespaceURI, kAstr); |
| fNamespaceURI = ((DOMDocumentImpl *)(castToNodeImpl(rootNode)->getOwnerDocument()))->getPooledString(namespaceURI); |
| } |
| |
| |
| DOMDeepNodeListImpl::~DOMDeepNodeListImpl() |
| { |
| } |
| |
| XMLSize_t DOMDeepNodeListImpl::getLength() const |
| { |
| // Reset cache to beginning of list |
| item(0); |
| |
| // Preload all matching elements. (Stops when we run out of subtree!) |
| item(INT_MAX); |
| return fCurrentIndexPlus1; |
| } |
| |
| |
| DOMNode *DOMDeepNodeListImpl::item(XMLSize_t index) const |
| { |
| return ((DOMDeepNodeListImpl*)this)->cacheItem(index); |
| } |
| |
| // Start from the first child and count forward, 0-based. index>length-1 |
| // should return 0. |
| // |
| // Attempts to do only work actually requested, cache work already |
| // done, and to flush that cache when the tree has changed. |
| // |
| // LIMITATION: ????? Unable to tell relevant tree-changes from |
| // irrelevant ones. Doing so in a really useful manner would seem |
| // to involve a tree-walk in its own right, or maintaining our data |
| // in a parallel tree. |
| DOMNode *DOMDeepNodeListImpl::cacheItem(XMLSize_t index) |
| { |
| XMLSize_t currentIndexPlus1 = fCurrentIndexPlus1; |
| DOMNode *currentNode = fCurrentNode; |
| |
| if (castToParentImpl(fRootNode)->changes() != fChanges) |
| { |
| // Tree changed. Do it all from scratch! |
| currentIndexPlus1 = 0; |
| currentNode = (DOMNode *)fRootNode; |
| fChanges = castToParentImpl(fRootNode)->changes(); |
| } |
| else if (currentIndexPlus1 > index+1) |
| { |
| // Interested in something before cached node. Do it all from scratch! |
| currentIndexPlus1 = 0; |
| currentNode = (DOMNode *)fRootNode; |
| } |
| else if (index+1 == currentIndexPlus1) |
| { |
| // What luck! User is interested in cached node. |
| return currentNode; |
| } |
| |
| DOMNode *nextNode = 0; |
| |
| // revisit - ???? How efficient is this loop? ???? |
| |
| // Start at the place in the tree at which we're |
| // currently pointing and count off nodes until we |
| // reach the node of interest or the end of the tree. |
| while (currentIndexPlus1 < index+1 && currentNode != 0) |
| { |
| nextNode = nextMatchingElementAfter(currentNode); |
| if (nextNode == 0) |
| break; |
| currentNode = nextNode; |
| currentIndexPlus1++; |
| } |
| |
| fCurrentNode = currentNode; |
| fCurrentIndexPlus1 = currentIndexPlus1; |
| |
| // If we found a node at the requested index, make that the current node |
| if (nextNode != 0) |
| { |
| return currentNode; |
| } |
| |
| // If we didn't find a node at the requested index, return 0 |
| return 0; |
| } |
| |
| |
| |
| /* Iterative tree-walker. When you have a Parent link, there's often no |
| need to resort to recursion. NOTE THAT only Element nodes are matched |
| since we're specifically supporting getElementsByTagName(). |
| */ |
| DOMNode *DOMDeepNodeListImpl::nextMatchingElementAfter(DOMNode *current) |
| { |
| DOMNode *next; |
| while (current != 0) |
| { |
| // Look down to first child. |
| if (current->hasChildNodes()) |
| { |
| current = current->getFirstChild(); |
| } |
| // Look right to sibling (but not from root!) |
| else |
| { |
| if (current != fRootNode && 0 != (next = current->getNextSibling())) |
| { |
| current = next; |
| } |
| // Look up and right (but not past root!) |
| else |
| { |
| next = 0; |
| for (; |
| current != fRootNode; // Stop on return to starting point |
| current = current->getParentNode()) |
| { |
| next = current->getNextSibling(); |
| if (next != 0) |
| break; |
| } |
| current = next; |
| } |
| } |
| |
| // Have we found an Element with the right tagName? |
| // ("*" matches anything.) |
| if (current != 0 && current != fRootNode && |
| current->getNodeType() == DOMNode::ELEMENT_NODE) { |
| DOMElement *currElement = (DOMElement *)current; |
| |
| if (!fMatchURIandTagname) { //DOM Level 1 |
| if (fMatchAll || |
| XMLString::equals(currElement->getTagName(), fTagName)) |
| return current; |
| } else { //DOM Level 2 |
| if (!fMatchAllURI && |
| !XMLString::equals(current->getNamespaceURI(), fNamespaceURI)) |
| continue; |
| |
| if (fMatchAll || |
| XMLString::equals(current->getLocalName(), fTagName)) |
| return current; |
| } |
| } |
| |
| // Otherwise continue walking the tree |
| } |
| // Fell out of tree-walk; no more instances found |
| return 0; |
| } |
| |
| XERCES_CPP_NAMESPACE_END |
| |