COSC_4P82_Assignment_1/lib/beagle-3.0.3/PACC/XML/Iterator.hpp

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8.1 KiB
C++

/*
* Portable Agile C++ Classes (PACC)
* Copyright (C) 2001-2003 by Marc Parizeau
* http://manitou.gel.ulaval.ca/~parizeau/PACC
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* Contact:
* Laboratoire de Vision et Systemes Numeriques
* Departement de genie electrique et de genie informatique
* Universite Laval, Quebec, Canada, G1K 7P4
* http://vision.gel.ulaval.ca
*
*/
/*!
* \file PACC/XML/Iterator.hpp
* \brief Class definition for the %XML node iterator.
* \author Marc Parizeau, Laboratoire de vision et systèmes numériques, Université Laval
* $Revision: 1.6.2.1 $
* $Date: 2007/09/10 18:24:10 $
*/
#ifndef PACC_XML_Iterator_hpp_
#define PACC_XML_Iterator_hpp_
#include "XML/Node.hpp"
#include "Util/Assert.hpp"
namespace PACC {
using namespace std;
namespace XML {
/*! \brief %Node iterator.
\author Marc Parizeau, Laboratoire de vision et systèmes numériques, Université Laval
\ingroup XML
A node iterator is used to iterate through sibling nodes, using an interface similar to STL bidirectional iterators. For example, to iterate through the childs of node \c lNode:
\code
Node lNode;
...
for(Iterator lChild = lNode.getFirstChild(); lChild; ++lChild) {
// process each child
...
}
\endcode
Operator* can be used to return a node reference, operator-> to return a node pointer, operator++ (both prefix and postfix) to skip to next sibling, and operator-- (both prefix and postfix) to skip to previous sibling.
A boolean casting operator is also available to test for end of sequence (see second term of for-statement above). An iterator pointing to a valid node always returns true while an invalid iterator returns false. An invalid iterator should never be dereferenced, incremented, or decremented.
*/
class Iterator {
public:
//! Construct an empty iterator.
Iterator(void) : mNode(0) {}
//! Construct an iterator for node pointer \c inNode.
Iterator(Node* inNode) : mNode(inNode) {}
//! Iterate to next sibling of current node (prefix version); return iterator pointing to next sibling.
Iterator& operator++(void) {
PACC_AssertM(mNode, "Cannot increment an invalid iterator!");
mNode = mNode->mNextSibling;
return *this;
}
//! Iterate to next sibling of current node (postfix version); return iterator pointing to current node.
Iterator operator++(int) {
PACC_AssertM(mNode, "Cannot increment an invalid iterator!");
Iterator lTmp = *this;
mNode = mNode->mNextSibling;
return lTmp;
}
//! Iterate to previous sibling of current node (prefix version); return iterator pointing to previous sibling.
Iterator& operator--(void) {
PACC_AssertM(mNode, "Cannot decrement an invalid iterator!");
if(mNode) mNode = mNode->mPrevSibling;
return *this;
}
//! Iterate to previous sibling of current node (postfix version); return iterator pointing to current node.
Iterator operator--(int) {
PACC_AssertM(mNode, "Cannot increment an invalid iterator!");
Iterator lTmp = *this;
mNode = mNode->mPrevSibling;
return lTmp;
}
//! Return reference to current node (const version).
Node& operator*(void) const {
PACC_AssertM(mNode, "Cannot dereference an invalid iterator!");
return *mNode;
}
//! Return pointer to current node (const version).
Node* operator->(void) const {
PACC_AssertM(mNode, "Invalid iterator!");
return mNode;
}
//! Return true if this iterator is the same as iterator \c inIter; false otherwise.
bool operator==(const Iterator& inIter) const {return mNode == inIter.mNode;}
//! Return true if this iterator is different from iterator \c inIter; false otherwise.
bool operator!=(const Iterator& inIter) const {return mNode != inIter.mNode;}
//! Cast Iterator into bool; return true for a valid iterator, false otherwise.
operator bool(void) const {return mNode != 0;}
protected:
Node* mNode; //!< Pointer to current node.
friend class ConstIterator;
};
/*! \brief %Node const iterator.
\author Marc Parizeau, Laboratoire de vision et syst&egrave;mes num&eacute;riques, Universit&eacute; Laval
\ingroup XML
A const node iterator is used to iterate through sibling nodes, using an interface similar to STL bidirectional const_iterators. For example, to iterate through the childs of node \c lNode:
\code
Node lNode;
...
for(ConstIterator lChild = lNode.getFirstChild(); lChild; ++lChild) {
// process each child
...
}
\endcode
Operator* can be used to return a node const reference, operator-> to return a node const pointer, operator++ (both prefix and postfix) to skip to next element, and operator-- (both prefix and postfix) to skip to next element.
A boolean casting operator is also available to test for end of sequence (see second term of for-statement above). An iterator pointing to a valid node always returns true while an invalid iterator returns false. An invalid iterator should never be dereferenced, incremented, or decremented.
*/
class ConstIterator {
public:
//! Construct an empty const iterator.
ConstIterator(void) : mNode(0) {}
//! Construct a const iterator for node pointer \c inNode.
ConstIterator(const Node* inNode) : mNode(inNode) {}
//! Construct a const iterator from a non const iterator \c inPos.
ConstIterator(const Iterator& inPos) : mNode(inPos.mNode) {}
//! Iterate to next sibling of current node (prefix version); return iterator pointing to next sibling.
ConstIterator& operator++(void) {
PACC_AssertM(mNode, "Cannot increment an invalid iterator!");
mNode = mNode->mNextSibling;
return *this;
}
//! Iterate to next sibling of current node (postfix version); return iterator pointing to current node.
ConstIterator operator++(int) {
PACC_AssertM(mNode, "Cannot increment an invalid iterator!");
ConstIterator lTmp = *this;
mNode = mNode->mNextSibling;
return lTmp;
}
//! Iterate to previous sibling of current node (prefix version); return iterator pointing to previous sibling.
ConstIterator& operator--(void) {
PACC_AssertM(mNode, "Cannot decrement an invalid iterator!");
mNode = mNode->mPrevSibling;
return *this;
}
//! Iterate to previous sibling of current node (postfix version); return iterator pointing to current node.
ConstIterator operator--(int) {
PACC_AssertM(mNode, "Cannot decrement an invalid iterator!");
ConstIterator lTmp = *this;
mNode = mNode->mPrevSibling;
return lTmp;
}
//! Return reference to current node (const version).
const Node& operator*(void) const {
PACC_AssertM(mNode, "Cannot dereference an invalid iterator!");
return *mNode;
}
//! Return pointer to current node (const version).
const Node* operator->(void) const {
PACC_AssertM(mNode, "Invalid iterator!");
return mNode;
}
//! Return true if this iterator is the same as iterator \c inIter; false otherwise.
bool operator==(const ConstIterator& inIter) const {return mNode == inIter.mNode;}
//! Return true if this iterator is different from iterator \c inIter; false otherwise.
bool operator!=(const ConstIterator& inIter) const {return mNode != inIter.mNode;}
//! Cast Iterator into bool; return true for a valid iterator, false otherwise.
operator bool(void) const {return mNode != 0;}
protected:
const Node* mNode; //!< Pointer to current node.
};
} // end of XML namespace
} // end of PACC namespace
#endif // PACC_XML_Iterator_hpp_