/*
* Copyright 1999-2002,2004 The Apache Software Foundation.
*
* Licensed 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: DOM_TreeWalker.hpp,v 1.5 2004/09/08 13:55:43 peiyongz Exp $
*/
#ifndef DOM_TreeWalker_HEADER_GUARD_
#define DOM_TreeWalker_HEADER_GUARD_
#include "DOM_Node.hpp"
#include "DOM_NodeFilter.hpp"
XERCES_CPP_NAMESPACE_BEGIN
class TreeWalkerImpl;
/**
* DOM_TreeWalker
objects are used to navigate a document tree or
* subtree using the view of the document defined by its whatToShow
* flags and any filters that are defined for the DOM_TreeWalker
. Any
* function which performs navigation using a DOM_TreeWalker
will
* automatically support any view defined by a DOM_TreeWalker
.
*
* Omitting nodes from the logical view of a subtree can result in a structure that is
* substantially different from the same subtree in the complete, unfiltered document. Nodes
* that are siblings in the DOM_TreeWalker view may be children of different, widely separated
* nodes in the original view. For instance, consider a Filter that skips all nodes except for
* Text nodes and the root node of a document. In the logical view that results, all text
* nodes will be siblings and appear as direct children of the root node, no matter how
* deeply nested the structure of the original document.
*
*/
class DEPRECATED_DOM_EXPORT DOM_TreeWalker {
public:
/** @name Constructors and assignment operator */
//@{
/**
* Default constructor.
*/
DOM_TreeWalker();
/**
* Copy constructor.
*
* @param other The object to be copied.
*/
DOM_TreeWalker(const DOM_TreeWalker &other);
/**
* Assignment operator.
*
* @param other The object to be copied.
*/
DOM_TreeWalker & operator = (const DOM_TreeWalker &other);
/**
* Assignment operator. This overloaded variant is provided for
* the sole purpose of setting a DOM_NodeIterator to null.
*
* @param val Only a value of 0, or null, is allowed.
*/
DOM_TreeWalker & operator = (const DOM_NullPtr *val);
//@}
/** @name Destructor. */
//@{
/**
* Destructor for DOM_TreeWalker.
*/
~DOM_TreeWalker();
//@}
/** @name Equality and Inequality operators. */
//@{
/**
* The equality operator.
*
* @param other The object reference with which this
object is compared
* @returns True if both DOM_TreeWalker
s refer to the same
* actual node, or are both null; return false otherwise.
*/
bool operator == (const DOM_TreeWalker & other)const;
/**
* Compare with a pointer. Intended only to allow a convenient
* comparison with null.
*/
bool operator == (const DOM_NullPtr *other) const;
/**
* The inequality operator. See operator ==.
*/
bool operator != (const DOM_TreeWalker & other) const;
/**
* Compare with a pointer. Intended only to allow a convenient
* comparison with null.
*
*/
bool operator != (const DOM_NullPtr * other) const;
//@}
/** @name Get functions. */
//@{
/**
* The root
node of the TreeWalker
, as specified
* when it was created.
*/
DOM_Node getRoot();
/**
* Return which node types are presented via the DOM_TreeWalker.
* These constants are defined in the DOM_NodeFilter interface.
*
*/
unsigned long getWhatToShow();
/**
* Return The filter used to screen nodes.
*
*/
DOM_NodeFilter* getFilter();
/**
* Return the expandEntityReferences flag.
* The value of this flag determines whether the children of entity reference
* nodes are visible to the DOM_TreeWalker. If false, they will be skipped over.
*
*/
bool getExpandEntityReferences();
/**
* Return the node at which the DOM_TreeWalker is currently positioned.
*
*/
DOM_Node getCurrentNode();
/**
* Moves to and returns the closest visible ancestor node of the current node.
* If the search for parentNode attempts to step upward from the DOM_TreeWalker's root
* node, or if it fails to find a visible ancestor node, this method retains the
* current position and returns null.
*
*/
DOM_Node parentNode();
/**
* Moves the DOM_TreeWalker
to the first child of the current node,
* and returns the new node. If the current node has no children, returns
* null
, and retains the current node.
*
*/
DOM_Node firstChild();
/**
* Moves the DOM_TreeWalker
to the last child of the current node, and
* returns the new node. If the current node has no children, returns
* null
, and retains the current node.
*
*/
DOM_Node lastChild();
/**
* Moves the DOM_TreeWalker
to the previous sibling of the current
* node, and returns the new node. If the current node has no previous sibling,
* returns null
, and retains the current node.
*
*/
DOM_Node previousSibling();
/**
* Moves the DOM_TreeWalker
to the next sibling of the current node,
* and returns the new node. If the current node has no next sibling, returns
* null
, and retains the current node.
*
*/
DOM_Node nextSibling();
/**
* Moves the DOM_TreeWalker
to the previous visible node in document
* order relative to the current node, and returns the new node. If the current
* node has no previous node,
* or if the search for previousNode attempts to step upward from the DOM_TreeWalker's
* root node, returns null
, and retains the current node.
*
*/
DOM_Node previousNode();
/**
* Moves the DOM_TreeWalker
to the next visible node in document order
* relative to the current node, and returns the new node. If the current node has
* no next node,
* or if the search for nextNode attempts to step upward from the DOM_TreeWalker's
* root node, returns null
, and retains the current node.
*
*/
DOM_Node nextNode();
//@}
/** @name Set functions. */
//@{
/**
* Set the node at which the DOM_TreeWalker is currently positioned.
*
*/
void setCurrentNode(DOM_Node currentNode);
//@}
protected:
DOM_TreeWalker(TreeWalkerImpl* impl);
friend class DOM_Document;
private:
TreeWalkerImpl* fImpl;
};
XERCES_CPP_NAMESPACE_END
#endif