class Poco::XML::Node
Overview
The Node interface is the primary datatype for the entire Document Object Model. More…
#include <Node.h> class Node: public Poco::XML::EventTarget { public: // typedefs typedef Poco::XML::NamespaceSupport NSMap; // enums enum { ELEMENT_NODE = 1, ATTRIBUTE_NODE, TEXT_NODE, CDATA_SECTION_NODE, ENTITY_REFERENCE_NODE, ENTITY_NODE, PROCESSING_INSTRUCTION_NODE, COMMENT_NODE, DOCUMENT_NODE, DOCUMENT_TYPE_NODE, DOCUMENT_FRAGMENT_NODE, NOTATION_NODE, }; // methods virtual const XMLString& nodeName() const = 0; const XMLString& nodeValue() const; virtual const XMLString& getNodeValue() const = 0; virtual void setNodeValue(const XMLString& value) = 0; virtual unsigned short nodeType() const = 0; virtual Node* parentNode() const = 0; virtual NodeList* childNodes() const = 0; virtual Node* firstChild() const = 0; virtual Node* lastChild() const = 0; virtual Node* previousSibling() const = 0; virtual Node* nextSibling() const = 0; virtual NamedNodeMap* attributes() const = 0; virtual Document* ownerDocument() const = 0; virtual Node* insertBefore( Node* newChild, Node* refChild ) = 0; virtual Node* replaceChild( Node* newChild, Node* oldChild ) = 0; virtual Node* removeChild(Node* oldChild) = 0; virtual Node* appendChild(Node* newChild) = 0; virtual bool hasChildNodes() const = 0; virtual Node* cloneNode(bool deep) const = 0; virtual void normalize() = 0; virtual bool isSupported( const XMLString& feature, const XMLString& version ) const = 0; virtual const XMLString& namespaceURI() const = 0; virtual XMLString prefix() const = 0; virtual const XMLString& localName() const = 0; virtual bool hasAttributes() const = 0; virtual XMLString innerText() const = 0; virtual Node* getNodeByPath(const XMLString& path) const = 0; virtual Node* getNodeByPathNS( const XMLString& path, const NSMap& nsMap ) const = 0; }; // direct descendants class AbstractNode;
Inherited Members
public: // methods void duplicate() const; void release() const; virtual void autoRelease() = 0; virtual void addEventListener( const XMLString& type, EventListener* listener, bool useCapture ) = 0; virtual void removeEventListener( const XMLString& type, EventListener* listener, bool useCapture ) = 0; virtual bool dispatchEvent(Event* evt) = 0;
Detailed Documentation
The Node interface is the primary datatype for the entire Document Object Model.
It represents a single node in the document tree. While all objects implementing the Node interface expose methods for dealing with children, not all objects implementing the Node interface may have children. For example, Text nodes may not have children, and adding children to such nodes results in a DOMException being raised.
The attributes nodeName, nodeValue and attributes are included as a mechanism to get at node information without casting down to the specific derived interface. In cases where there is no obvious mapping of these attributes for a specific nodeType (e.g., nodeValue for an Element or attributes for a Comment), this returns null. Note that the specialized interfaces may contain additional and more convenient mechanisms to get and set the relevant information.
This implementation differs in some ways from the W3C DOM recommendations. For example, the DOM specifies that some methods can return null strings. Instead of null strings, this implementation always returns empty strings.
Enum Values
ELEMENT_NODE
The node is an Element.
ATTRIBUTE_NODE
The node is an Attr.
TEXT_NODE
The node is a Text node.
CDATA_SECTION_NODE
The node is a CDATASection.
ENTITY_REFERENCE_NODE
The node is an EntityReference.
ENTITY_NODE
The node is an Entity.
PROCESSING_INSTRUCTION_NODE
The node is a ProcessingInstruction.
COMMENT_NODE
The node is a Comment.
DOCUMENT_NODE
The node is a Document.
DOCUMENT_TYPE_NODE
The node is a DocumentType.
DOCUMENT_FRAGMENT_NODE
The node is a DocumentFragment.
NOTATION_NODE
The node is a Notation.
Methods
virtual const XMLString& nodeName() const = 0
Returns the name of this node, depending on its type.
const XMLString& nodeValue() const
Returns the value of this node, depending on its type.
virtual const XMLString& getNodeValue() const = 0
Returns the value of this node, depending on its type.
virtual void setNodeValue(const XMLString& value) = 0
Sets the value of this node.
Throws an exception if the node is read-only.
virtual unsigned short nodeType() const = 0
Returns a code representing the type of the underlying object.
virtual Node* parentNode() const = 0
The parent of this node.
All nodes, except Attr, Document, DocumentFragment, Entity, and Notation may have a parent. However, if a node has just been created and not yet added to the tree, or if it has been removed from the tree, this is null.
virtual NodeList* childNodes() const = 0
Returns a NodeList containing all children of this node.
The returned NodeList must be released with a call to release() when no longer needed.
virtual Node* firstChild() const = 0
Returns the first child of this node.
If there is no such node, this returns null.
virtual Node* lastChild() const = 0
Returns the last child of this node.
If there is no such node, this returns null.
virtual Node* previousSibling() const = 0
Returns the node immediately preceding this node.
If there is no such node, this returns null.
virtual Node* nextSibling() const = 0
Returns the node immediately following this node.
If there is no such node, this returns null.
virtual NamedNodeMap* attributes() const = 0
Returns a NamedNodeMap containing the attributes of this node (if it is an Element) or null otherwise.
The returned NamedNodeMap must be released with a call to release() when no longer needed.
virtual Document* ownerDocument() const = 0
Returns the Document object associated with this node.
This is also the Document object used to create new nodes. When this node is a Document, this is null.
virtual Node* insertBefore( Node* newChild, Node* refChild ) = 0
Inserts the node newChild before the existing child node refChild.
If refChild is null, insert newChild at the end of the list of children. If newChild is a DocumentFragment object, all of its children are inserted in the same order, before refChild. If the newChild is already in the tree, it is first removed.
virtual Node* replaceChild( Node* newChild, Node* oldChild ) = 0
Replaces the child node oldChild with newChild in the list of children, and returns the oldChild node.
If newChild is a DocumentFragment object, oldChild is replaced by all of the DocumentFragment children, which are inserted in the same order. If the newChild is already in the tree, it is first removed.
virtual Node* removeChild(Node* oldChild) = 0
Removes the child node indicated by oldChild from the list of children and returns it.
virtual Node* appendChild(Node* newChild) = 0
Appends the node newChild to the end of the list of children of this node.
If newChild is already in the tree, it is first removed.
virtual bool hasChildNodes() const = 0
This is a convenience method to allow easy determination of whether a node has any children.
Returns true if the node has any children, false otherwise.
virtual Node* cloneNode(bool deep) const = 0
Returns a duplicate of this node, i.e., serves as a generic copy constructor for nodes.
The duplicate node has no parent; (parentNode is null.). Cloning an Element copies all attributes and their values, including those generated by the XML processor to represent defaulted attributes, but this method does not copy any text it contains unless it is a deep clone, since the text is contained in a child Text node. Cloning an Attribute directly, as opposed to be cloned as part of an Element cloning operation, returns a specified attribute (specified is true). Cloning any other type of node simply returns a copy of this node. Note that cloning an immutable subtree results in a mutable copy, but the children of an EntityReference clone are readonly. In addition, clones of unspecified Attr nodes are specified. And, cloning Document, DocumentType, Entity, and Notation nodes is implementation dependent.
virtual void normalize() = 0
Puts all Text nodes in the full depth of the sub-tree underneath this Node, including attribute nodes, into a “normal” form where only structure (e.g., elements, comments, processing instructions, CDATA sections, and entity references) separates Text nodes, i.e., there are neither adjacent Text nodes nor empty Text nodes.
This can be used to ensure that the DOM view of a document is the same as if it were saved and re-loaded, and is useful when operations (such as XPointer lookups) that depend on a particular document tree structure are to be used.
Note: In cases where the document contains CDATASections, the normalize operation alone may not be sufficient, since XPointers do not differentiate between Text nodes and CDATASection nodes.
virtual bool isSupported( const XMLString& feature, const XMLString& version ) const = 0
Tests whether the DOM implementation implements a specific feature and that feature is supported by this node.
virtual const XMLString& namespaceURI() const = 0
Returns the namespace URI of the node.
This is not a computed value that is the result of a namespace lookup based on an examination of the namespace declarations in scope. It is merely the namespace URI given at creation time.
For nodes of any type other than ELEMENT_NODE and ATTRIBUTE_NODE and nodes created with a DOM Level 1 method, such as createElement from the Document interface, this is always the empty string.
virtual XMLString prefix() const = 0
Returns the namespace prefix from the qualified name of the node.
virtual const XMLString& localName() const = 0
Returns the local name of the node.
virtual bool hasAttributes() const = 0
Returns whether this node (if it is an element) has any attributes.
virtual XMLString innerText() const = 0
Returns a string containing the concatenated values of the node and all its child nodes.
This method is not part of the W3C Document Object Model.
virtual Node* getNodeByPath(const XMLString& path) const = 0
Searches a node (element or attribute) based on a simplified XPath expression.
Only simple XPath expressions are supported. These are the slash notation for specifying paths to elements, and the square bracket expression for finding elements by their index, by attribute value, or finding attributes by names.
The slash at the beginning is optional, the evaluation always starts at this element. A double-slash at the beginning recursively searches the entire subtree for the first element.
Examples:
elem1/elem2/elem3 /elem1/elem2/elem3 /elem1/elem2[1] /elem1/elem2[@attr1] /elem1/elem2[@attr1='value'] //elem2[@attr1='value'] //[@attr1='value']
This method is an extension to the W3C Document Object Model.
virtual Node* getNodeByPathNS( const XMLString& path, const NSMap& nsMap ) const = 0
Searches a node (element or attribute) based on a simplified XPath expression.
The given NSMap must contain mappings from namespace prefixes to namespace URIs for all namespace prefixes used in the path expression.
Only simple XPath expressions are supported. These are the slash notation for specifying paths to elements, and the square bracket expression for finding elements by their index, by attribute value, or finding attributes by names.
The slash at the beginning is optional, the evaluation always starts at this element. A double-slash at the beginning recursively searches the entire subtree for the first element.
Examples:
/ns1:elem1/ns2:elem2/ns2:elem3 /ns1:elem1/ns2:elem2[1] /ns1:elem1/ns2:elem2[@attr1] /ns1:elem1/ns2:elem2[@attr1='value'] //ns2:elem2[@ns1:attr1='value'] //[@ns1:attr1='value']
This method is an extension to the W3C Document Object Model.