1. Document Object Model Core

1.1 Overview of the DOM Core Interfaces

1.2 Basic Types

To ensure interoperability, this specification specifies the following basic types used in various DOM modules. Even though the DOM uses the basic types in the interfaces, bindings may use different types and normative bindings are only given for Java and ECMAScript in this specification.

1.3 General Considerations

1.4 Fundamental Interfaces: Core Module

The interfaces within this section are considered fundamental, and must be fully implemented by all conforming implementations of the DOM, including all HTML DOM implementations [DOM Level 2 HTML], unless otherwise specified.

A DOM application may use the DOMImplementation.hasFeature(feature, version) method with parameter values "Core" and "3.0" (respectively) to determine whether or not this module is supported by the implementation. Any implementation that conforms to DOM Level 3 or a DOM Level 3 module must conform to the Core module. Please refer to additional information about conformance in this specification. The DOM Level 3 Core module is backward compatible with the DOM Level 2 Core [DOM Level 2 Core] module, i.e. a DOM Level 3 Core implementation who returns true for "Core" with the version number "3.0" must also return true for this feature when the version number is "2.0", "" or, null. Exception DOMException

DOM operations only raise exceptions in "exceptional" circumstances, i.e., when an operation is impossible to perform (either for logical reasons, because data is lost, or because the implementation has become unstable). In general, DOM methods return specific error values in ordinary processing situations, such as out-of-bound errors when using NodeList.

Implementations should raise other exceptions under other circumstances. For example, implementations should raise an implementation-dependent exception if a null argument is passed when null was not expected.

Some languages and object systems do not support the concept of exceptions. For such systems, error conditions may be indicated using native error reporting mechanisms. For some bindings, for example, methods may return error codes similar to those listed in the corresponding method descriptions.
IDL Definition

Definition group ExceptionCode

An integer indicating the type of error generated.

Note: Other numeric codes are reserved for W3C for possible future use.

Defined Constants DOMSTRING_SIZE_ERR If the specified range of text does not fit into a DOMString. HIERARCHY_REQUEST_ERR If any Node is inserted somewhere it doesn't belong. INDEX_SIZE_ERR If index or size is negative, or greater than the allowed value. INUSE_ATTRIBUTE_ERR If an attempt is made to add an attribute that is already in use elsewhere. INVALID_ACCESS_ERR, introduced in DOM Level 2. If a parameter or an operation is not supported by the underlying object. INVALID_CHARACTER_ERR If an invalid or illegal character is specified, such as in an XML name. INVALID_MODIFICATION_ERR, introduced in DOM Level 2. If an attempt is made to modify the type of the underlying object. INVALID_STATE_ERR, introduced in DOM Level 2. If an attempt is made to use an object that is not, or is no longer, usable. NAMESPACE_ERR, introduced in DOM Level 2. If an attempt is made to create or change an object in a way which is incorrect with regard to namespaces. NOT_FOUND_ERR If an attempt is made to reference a Node in a context where it does not exist. NOT_SUPPORTED_ERR If the implementation does not support the requested type of object or operation. NO_DATA_ALLOWED_ERR If data is specified for a Node which does not support data. NO_MODIFICATION_ALLOWED_ERR If an attempt is made to modify an object where modifications are not allowed. SYNTAX_ERR, introduced in DOM Level 2. If an invalid or illegal string is specified. TYPE_MISMATCH_ERR, introduced in DOM Level 3. If the type of an object is incompatible with the expected type of the parameter associated to the object. VALIDATION_ERR, introduced in DOM Level 3. If a call to a method such as insertBefore or removeChild would make the Node invalid with respect to "partial validity", this exception would be raised and the operation would not be done. This code is used in [DOM Level 3 Validation]. Refer to this specification for further information. WRONG_DOCUMENT_ERR If a Node is used in a different document than the one that created it (that doesn't support it). Interface DOMStringList (introduced in DOM Level 3)

The DOMStringList interface provides the abstraction of an ordered collection of DOMString values, without defining or constraining how this collection is implemented. The items in the DOMStringList are accessible via an integral index, starting from 0.
IDL Definition

Attributes length of type unsigned long, readonly The number of DOMStrings in the list. The range of valid child node indices is 0 to length-1 inclusive.
Methods contains item Interface NameList (introduced in DOM Level 3)

The NameList interface provides the abstraction of an ordered collection of parallel pairs of name and namespace values (which could be null values), without defining or constraining how this collection is implemented. The items in the NameList are accessible via an integral index, starting from 0.
IDL Definition

Attributes length of type unsigned long, readonly The number of pairs (name and namespaceURI) in the list. The range of valid child node indices is 0 to length-1 inclusive.
Methods contains containsNS getName getNamespaceURI Interface DOMImplementationList (introduced in DOM Level 3)

The DOMImplementationList interface provides the abstraction of an ordered collection of DOM implementations, without defining or constraining how this collection is implemented. The items in the DOMImplementationList are accessible via an integral index, starting from 0.
IDL Definition

Attributes length of type unsigned long, readonly The number of DOMImplementations in the list. The range of valid child node indices is 0 to length-1 inclusive.
Methods item Interface DOMImplementationSource (introduced in DOM Level 3)

This interface permits a DOM implementer to supply one or more implementations, based upon requested features and versions, as specified in DOM Features. Each implemented DOMImplementationSource object is listed in the binding-specific list of available sources so that its DOMImplementation objects are made available.
IDL Definition

Methods getDOMImplementation getDOMImplementationList Interface DOMImplementation

The DOMImplementation interface provides a number of methods for performing operations that are independent of any particular instance of the document object model.
IDL Definition

Methods createDocument introduced in DOM Level 2 createDocumentType introduced in DOM Level 2 getFeature introduced in DOM Level 3 hasFeature Interface DocumentFragment

DocumentFragment is a "lightweight" or "minimal" Document object. It is very common to want to be able to extract a portion of a document's tree or to create a new fragment of a document. Imagine implementing a user command like cut or rearranging a document by moving fragments around. It is desirable to have an object which can hold such fragments and it is quite natural to use a Node for this purpose. While it is true that a Document object could fulfill this role, a Document object can potentially be a heavyweight object, depending on the underlying implementation. What is really needed for this is a very lightweight object. DocumentFragment is such an object.

Furthermore, various operations -- such as inserting nodes as children of another Node -- may take DocumentFragment objects as arguments; this results in all the child nodes of the DocumentFragment being moved to the child list of this node.

The children of a DocumentFragment node are zero or more nodes representing the tops of any sub-trees defining the structure of the document. DocumentFragment nodes do not need to be well-formed XML documents (although they do need to follow the rules imposed upon well-formed XML parsed entities, which can have multiple top nodes). For example, a DocumentFragment might have only one child and that child node could be a Text node. Such a structure model represents neither an HTML document nor a well-formed XML document.

When a DocumentFragment is inserted into a Document (or indeed any other Node that may take children) the children of the DocumentFragment and not the DocumentFragment itself are inserted into the Node. This makes the DocumentFragment very useful when the user wishes to create nodes that are siblings; the DocumentFragment acts as the parent of these nodes so that the user can use the standard methods from the Node interface, such as Node.insertBefore and Node.appendChild.
IDL Definition

Interface Document

The Document interface represents the entire HTML or XML document. Conceptually, it is the root of the document tree, and provides the primary access to the document's data.

Since elements, text nodes, comments, processing instructions, etc. cannot exist outside the context of a Document, the Document interface also contains the factory methods needed to create these objects. The Node objects created have a ownerDocument attribute which associates them with the Document within whose context they were created.
IDL Definition

Attributes doctype of type DocumentType, readonly, modified in DOM Level 3 The Document Type Declaration (see DocumentType) associated with this document. For XML documents without a document type declaration this returns null. For HTML documents, a DocumentType object may be returned, independently of the presence or absence of document type declaration in the HTML document.
This provides direct access to the DocumentType node, child node of this Document. This node can be set at document creation time and later changed through the use of child nodes manipulation methods, such as Node.insertBefore, or Node.replaceChild. Note, however, that while some implementations may instantiate different types of Document objects supporting additional features than the "Core", such as "HTML" [DOM Level 2 HTML], based on the DocumentType specified at creation time, changing it afterwards is very unlikely to result in a change of the features supported.
documentElement of type Element, readonly This is a convenience attribute that allows direct access to the child node that is the document element of the document.
documentURI of type DOMString, introduced in DOM Level 3 The location of the document or null if undefined or if the Document was created using DOMImplementation.createDocument. No lexical checking is performed when setting this attribute; this could result in a null value returned when using Node.baseURI.
Beware that when the Document supports the feature "HTML" [DOM Level 2 HTML], the href attribute of the HTML BASE element takes precedence over this attribute when computing Node.baseURI.
domConfig of type DOMConfiguration, readonly, introduced in DOM Level 3 The configuration used when Document.normalizeDocument() is invoked.
implementation of type DOMImplementation, readonly The DOMImplementation object that handles this document. A DOM application may use objects from multiple implementations.
inputEncoding of type DOMString, readonly, introduced in DOM Level 3 An attribute specifying the encoding used for this document at the time of the parsing. This is null when it is not known, such as when the Document was created in memory.
strictErrorChecking of type boolean, introduced in DOM Level 3 An attribute specifying whether error checking is enforced or not. When set to false, the implementation is free to not test every possible error case normally defined on DOM operations, and not raise any DOMException on DOM operations or report errors while using Document.normalizeDocument(). In case of error, the behavior is undefined. This attribute is true by default.
xmlEncoding of type DOMString, readonly, introduced in DOM Level 3 An attribute specifying, as part of the XML declaration, the encoding of this document. This is null when unspecified or when it is not known, such as when the Document was created in memory.
xmlStandalone of type boolean, introduced in DOM Level 3 An attribute specifying, as part of the XML declaration, whether this document is standalone. This is false when unspecified.

Note: No verification is done on the value when setting this attribute. Applications should use Document.normalizeDocument() with the "validate" parameter to verify if the value matches the validity constraint for standalone document declaration as defined in [XML 1.0].

xmlVersion of type DOMString, introduced in DOM Level 3 An attribute specifying, as part of the XML declaration, the version number of this document. If there is no declaration and if this document supports the "XML" feature, the value is "1.0". If this document does not support the "XML" feature, the value is always null. Changing this attribute will affect methods that check for invalid characters in XML names. Application should invoke Document.normalizeDocument() in order to check for invalid characters in the Nodes that are already part of this Document.
DOM applications may use the DOMImplementation.hasFeature(feature, version) method with parameter values "XMLVersion" and "1.0" (respectively) to determine if an implementation supports [XML 1.0]. DOM applications may use the same method with parameter values "XMLVersion" and "1.1" (respectively) to determine if an implementation supports [XML 1.1]. In both cases, in order to support XML, an implementation must also support the "XML" feature defined in this specification. Document objects supporting a version of the "XMLVersion" feature must not raise a NOT_SUPPORTED_ERR exception for the same version number when using Document.xmlVersion.
Methods adoptNode introduced in DOM Level 3 createAttribute createAttributeNS introduced in DOM Level 2 createCDATASection createComment createDocumentFragment createElement createElementNS introduced in DOM Level 2 createEntityReference createProcessingInstruction createTextNode getElementById introduced in DOM Level 2 getElementsByTagName getElementsByTagNameNS introduced in DOM Level 2 importNode introduced in DOM Level 2 normalizeDocument introduced in DOM Level 3 renameNode introduced in DOM Level 3 Interface Node

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.
IDL Definition

Definition group NodeType

An integer indicating which type of node this is.

Note: Numeric codes up to 200 are reserved to W3C for possible future use.

Defined Constants ATTRIBUTE_NODE The node is an Attr. CDATA_SECTION_NODE The node is a CDATASection. COMMENT_NODE The node is a Comment. DOCUMENT_FRAGMENT_NODE The node is a DocumentFragment. DOCUMENT_NODE The node is a Document. DOCUMENT_TYPE_NODE The node is a DocumentType. ELEMENT_NODE The node is an Element. ENTITY_NODE The node is an Entity. ENTITY_REFERENCE_NODE The node is an EntityReference. NOTATION_NODE The node is a Notation. PROCESSING_INSTRUCTION_NODE The node is a ProcessingInstruction. TEXT_NODE The node is a Text node.

The values of nodeName, nodeValue, and attributes vary according to the node type as follows:

Interface nodeName nodeValue attributes

Attr	same as Attr.name	same as Attr.value	null
CDATASection	"#cdata-section"	same as CharacterData.data, the content of the CDATA Section	null
Comment	"#comment"	same as CharacterData.data, the content of the comment	null
Document	"#document"	null	null
DocumentFragment	"#document-fragment"	null	null
DocumentType	same as DocumentType.name	null	null
Element	same as Element.tagName	null	NamedNodeMap
Entity	entity name	null	null
EntityReference	name of entity referenced	null	null
Notation	notation name	null	null
ProcessingInstruction	same as ProcessingInstruction.target	same as ProcessingInstruction.data	null
Text	"#text"	same as CharacterData.data, the content of the text node	null

Definition group DocumentPosition

A bitmask indicating the relative document position of a node with respect to another node.

If the two nodes being compared are the same node, then no flags are set on the return.

Otherwise, the order of two nodes is determined by looking for common containers -- containers which contain both. A node directly contains any child nodes. A node also directly contains any other nodes attached to it such as attributes contained in an element or entities and notations contained in a document type. Nodes contained in contained nodes are also contained, but less-directly as the number of intervening containers increases.

If there is no common container node, then the order is based upon order between the root container of each node that is in no container. In this case, the result is disconnected and implementation-specific. This result is stable as long as these outer-most containing nodes remain in memory and are not inserted into some other containing node. This would be the case when the nodes belong to different documents or fragments, and cloning the document or inserting a fragment might change the order.

If one of the nodes being compared contains the other node, then the container precedes the contained node, and reversely the contained node follows the container. For example, when comparing an element against its own attribute or child, the element node precedes its attribute node and its child node, which both follow it.

If neither of the previous cases apply, then there exists a most-direct container common to both nodes being compared. In this case, the order is determined based upon the two determining nodes directly contained in this most-direct common container that either are or contain the corresponding nodes being compared.

If these two determining nodes are both child nodes, then the natural DOM order of these determining nodes within the containing node is returned as the order of the corresponding nodes. This would be the case, for example, when comparing two child elements of the same element.

If one of the two determining nodes is a child node and the other is not, then the corresponding node of the child node follows the corresponding node of the non-child node. This would be the case, for example, when comparing an attribute of an element with a child element of the same element.

If neither of the two determining node is a child node and one determining node has a greater value of nodeType than the other, then the corresponding node precedes the other. This would be the case, for example, when comparing an entity of a document type against a notation of the same document type.

If neither of the two determining node is a child node and nodeType is the same for both determining nodes, then an implementation-dependent order between the determining nodes is returned. This order is stable as long as no nodes of the same nodeType are inserted into or removed from the direct container. This would be the case, for example, when comparing two attributes of the same element, and inserting or removing additional attributes might change the order between existing attributes. Defined Constants DOCUMENT_POSITION_CONTAINED_BY The node is contained by the reference node. A node which is contained is always following, too. DOCUMENT_POSITION_CONTAINS The node contains the reference node. A node which contains is always preceding, too. DOCUMENT_POSITION_DISCONNECTED The two nodes are disconnected. Order between disconnected nodes is always implementation-specific. DOCUMENT_POSITION_FOLLOWING The node follows the reference node. DOCUMENT_POSITION_IMPLEMENTATION_SPECIFIC The determination of preceding versus following is implementation-specific. DOCUMENT_POSITION_PRECEDING The second node precedes the reference node. Attributes attributes of type NamedNodeMap, readonly A NamedNodeMap containing the attributes of this node (if it is an Element) or null otherwise.
baseURI of type DOMString, readonly, introduced in DOM Level 3 The absolute base URI of this node or null if the implementation wasn't able to obtain an absolute URI. This value is computed as described in Base URIs. However, when the Document supports the feature "HTML" [DOM Level 2 HTML], the base URI is computed using first the value of the href attribute of the HTML BASE element if any, and the value of the documentURI attribute from the Document interface otherwise.
childNodes of type NodeList, readonly A NodeList that contains all children of this node. If there are no children, this is a NodeList containing no nodes.
firstChild of type Node, readonly The first child of this node. If there is no such node, this returns null.
lastChild of type Node, readonly The last child of this node. If there is no such node, this returns null.
localName of type DOMString, readonly, introduced in DOM Level 2 Returns the local part of the qualified name of this node.
For nodes of any type other than ELEMENT_NODE and ATTRIBUTE_NODE and nodes created with a DOM Level 1 method, such as Document.createElement(), this is always null.
namespaceURI of type DOMString, readonly, introduced in DOM Level 2 The namespace URI of this node, or null if it is unspecified (see XML Namespaces).
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 Document.createElement(), this is always null.

Note: Per the Namespaces in XML Specification [XML Namespaces] an attribute does not inherit its namespace from the element it is attached to. If an attribute is not explicitly given a namespace, it simply has no namespace.

nextSibling of type Node, readonly The node immediately following this node. If there is no such node, this returns null.
nodeName of type DOMString, readonly The name of this node, depending on its type; see the table above.
nodeType of type unsigned short, readonly A code representing the type of the underlying object, as defined above.
nodeValue of type DOMString The value of this node, depending on its type; see the table above. When it is defined to be null, setting it has no effect, including if the node is read-only.
ownerDocument of type Document, readonly, modified in DOM Level 2 The Document object associated with this node. This is also the Document object used to create new nodes. When this node is a Document or a DocumentType which is not used with any Document yet, this is null.
parentNode of type Node, readonly 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.
prefix of type DOMString, introduced in DOM Level 2 The namespace prefix of this node, or null if it is unspecified. When it is defined to be null, setting it has no effect, including if the node is read-only.
Note that setting this attribute, when permitted, changes the nodeName attribute, which holds the qualified name, as well as the tagName and name attributes of the Element and Attr interfaces, when applicable.
Setting the prefix to null makes it unspecified, setting it to an empty string is implementation dependent.
Note also that changing the prefix of an attribute that is known to have a default value, does not make a new attribute with the default value and the original prefix appear, since the namespaceURI and localName do not change.
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 null.
previousSibling of type Node, readonly The node immediately preceding this node. If there is no such node, this returns null.
textContent of type DOMString, introduced in DOM Level 3 This attribute returns the text content of this node and its descendants. When it is defined to be null, setting it has no effect. On setting, any possible children this node may have are removed and, if it the new string is not empty or null, replaced by a single Text node containing the string this attribute is set to.
On getting, no serialization is performed, the returned string does not contain any markup. No whitespace normalization is performed and the returned string does not contain the white spaces in element content (see the attribute Text.isElementContentWhitespace). Similarly, on setting, no parsing is performed either, the input string is taken as pure textual content.
The string returned is made of the text content of this node depending on its type, as defined below: Node type Content

ELEMENT_NODE, ATTRIBUTE_NODE, ENTITY_NODE, ENTITY_REFERENCE_NODE, DOCUMENT_FRAGMENT_NODE	concatenation of the textContent attribute value of every child node, excluding COMMENT_NODE and PROCESSING_INSTRUCTION_NODE nodes. This is the empty string if the node has no children.
TEXT_NODE, CDATA_SECTION_NODE, COMMENT_NODE, PROCESSING_INSTRUCTION_NODE	nodeValue
DOCUMENT_NODE, DOCUMENT_TYPE_NODE, NOTATION_NODE	null

Methods appendChild modified in DOM Level 3 cloneNode compareDocumentPosition introduced in DOM Level 3 getFeature introduced in DOM Level 3 getUserData introduced in DOM Level 3 hasAttributes introduced in DOM Level 2 hasChildNodes insertBefore modified in DOM Level 3 isDefaultNamespace introduced in DOM Level 3 isEqualNode introduced in DOM Level 3 isSameNode introduced in DOM Level 3 isSupported introduced in DOM Level 2 lookupNamespaceURI introduced in DOM Level 3 lookupPrefix introduced in DOM Level 3 normalize modified in DOM Level 3 removeChild modified in DOM Level 3 replaceChild modified in DOM Level 3 setUserData introduced in DOM Level 3 Interface NodeList

The NodeList interface provides the abstraction of an ordered collection of nodes, without defining or constraining how this collection is implemented. NodeList objects in the DOM are live.

The items in the NodeList are accessible via an integral index, starting from 0.
IDL Definition

Attributes length of type unsigned long, readonly The number of nodes in the list. The range of valid child node indices is 0 to length-1 inclusive.
Methods item Interface NamedNodeMap

Objects implementing the NamedNodeMap interface are used to represent collections of nodes that can be accessed by name. Note that NamedNodeMap does not inherit from NodeList; NamedNodeMaps are not maintained in any particular order. Objects contained in an object implementing NamedNodeMap may also be accessed by an ordinal index, but this is simply to allow convenient enumeration of the contents of a NamedNodeMap, and does not imply that the DOM specifies an order to these Nodes.

NamedNodeMap objects in the DOM are live.
IDL Definition

Attributes length of type unsigned long, readonly The number of nodes in this map. The range of valid child node indices is 0 to length-1 inclusive.
Methods getNamedItem getNamedItemNS introduced in DOM Level 2 item removeNamedItem removeNamedItemNS introduced in DOM Level 2 setNamedItem setNamedItemNS introduced in DOM Level 2 Interface CharacterData

The CharacterData interface extends Node with a set of attributes and methods for accessing character data in the DOM. For clarity this set is defined here rather than on each object that uses these attributes and methods. No DOM objects correspond directly to CharacterData, though Text and others do inherit the interface from it. All offsets in this interface start from 0.

As explained in the DOMString interface, text strings in the DOM are represented in UTF-16, i.e. as a sequence of 16-bit units. In the following, the term 16-bit units is used whenever necessary to indicate that indexing on CharacterData is done in 16-bit units.
IDL Definition

Attributes data of type DOMString The character data of the node that implements this interface. The DOM implementation may not put arbitrary limits on the amount of data that may be stored in a CharacterData node. However, implementation limits may mean that the entirety of a node's data may not fit into a single DOMString. In such cases, the user may call substringData to retrieve the data in appropriately sized pieces.
length of type unsigned long, readonly The number of 16-bit units that are available through data and the substringData method below. This may have the value zero, i.e., CharacterData nodes may be empty.
Methods appendData deleteData insertData replaceData substringData Interface Attr

The Attr interface represents an attribute in an Element object. Typically the allowable values for the attribute are defined in a schema associated with the document.

Attr objects inherit the Node interface, but since they are not actually child nodes of the element they describe, the DOM does not consider them part of the document tree. Thus, the Node attributes parentNode, previousSibling, and nextSibling have a null value for Attr objects. The DOM takes the view that attributes are properties of elements rather than having a separate identity from the elements they are associated with; this should make it more efficient to implement such features as default attributes associated with all elements of a given type. Furthermore, Attr nodes may not be immediate children of a DocumentFragment. However, they can be associated with Element nodes contained within a DocumentFragment. In short, users and implementors of the DOM need to be aware that Attr nodes have some things in common with other objects inheriting the Node interface, but they also are quite distinct.

The attribute's effective value is determined as follows: if this attribute has been explicitly assigned any value, that value is the attribute's effective value; otherwise, if there is a declaration for this attribute, and that declaration includes a default value, then that default value is the attribute's effective value; otherwise, the attribute does not exist on this element in the structure model until it has been explicitly added. Note that the Node.nodeValue attribute on the Attr instance can also be used to retrieve the string version of the attribute's value(s).

If the attribute was not explicitly given a value in the instance document but has a default value provided by the schema associated with the document, an attribute node will be created with specified set to false. Removing attribute nodes for which a default value is defined in the schema generates a new attribute node with the default value and specified set to false. If validation occurred while invoking Document.normalizeDocument(), attribute nodes with specified equals to false are recomputed according to the default attribute values provided by the schema. If no default value is associate with this attribute in the schema, the attribute node is discarded.

In XML, where the value of an attribute can contain entity references, the child nodes of the Attr node may be either Text or EntityReference nodes (when these are in use; see the description of EntityReference for discussion).

The DOM Core represents all attribute values as simple strings, even if the DTD or schema associated with the document declares them of some specific type such as tokenized.

The way attribute value normalization is performed by the DOM implementation depends on how much the implementation knows about the schema in use. Typically, the value and nodeValue attributes of an Attr node initially returns the normalized value given by the parser. It is also the case after Document.normalizeDocument() is called (assuming the right options have been set). But this may not be the case after mutation, independently of whether the mutation is performed by setting the string value directly or by changing the Attr child nodes. In particular, this is true when character references are involved, given that they are not represented in the DOM and they impact attribute value normalization. On the other hand, if the implementation knows about the schema in use when the attribute value is changed, and it is of a different type than CDATA, it may normalize it again at that time. This is especially true of specialized DOM implementations, such as SVG DOM implementations, which store attribute values in an internal form different from a string.

The following table gives some examples of the relations between the attribute value in the original document (parsed attribute), the value as exposed in the DOM, and the serialization of the value:

Examples Parsed attribute value Initial Attr.value Serialized attribute value

Character reference	"x²=5"	"x²=5"	"x²=5"
Built-in character entity	"y&lt;6"	"y<6"	"y&lt;6"
Literal newline between	"x=5&#10;y=6"	"x=5 y=6"	"x=5&#10;y=6"
Normalized newline between	"x=5 y=6"	"x=5 y=6"	"x=5 y=6"
Entity e with literal newline	<!ENTITY e '...&#10;...'> [...]> "x=5&e;y=6"	Dependent on Implementation and Load Options	Dependent on Implementation and Load/Save Options

IDL Definition
Attributes isId of type boolean, readonly, introduced in DOM Level 3 Returns whether this attribute is known to be of type ID (i.e. to contain an identifier for its owner element) or not. When it is and its value is unique, the ownerElement of this attribute can be retrieved using the method Document.getElementById. The implementation could use several ways to determine if an attribute node is known to contain an identifier:

• If validation occurred using an XML Schema [XML Schema Part 1] while loading the document or while invoking Document.normalizeDocument(), the post-schema-validation infoset contributions (PSVI contributions) values are used to determine if this attribute is a schema-determined ID attribute using the schema-determined ID definition in [XPointer].
• If validation occurred using a DTD while loading the document or while invoking Document.normalizeDocument(), the infoset [type definition] value is used to determine if this attribute is a DTD-determined ID attribute using the DTD-determined ID definition in [XPointer].
• from the use of the methods Element.setIdAttribute(), Element.setIdAttributeNS(), or Element.setIdAttributeNode(), i.e. it is an user-determined ID attribute;

  Note: XPointer framework (see section 3.2 in [XPointer]) consider the DOM user-determined ID attribute as being part of the XPointer externally-determined ID definition.

• using mechanisms that are outside the scope of this specification, it is then an externally-determined ID attribute. This includes using schema languages different from XML schema and DTD.

If validation occurred while invoking Document.normalizeDocument(), all user-determined ID attributes are reset and all attribute nodes ID information are then reevaluated in accordance to the schema used. As a consequence, if the Attr.schemaTypeInfo attribute contains an ID type, isId will always return true.
name of type DOMString, readonly Returns the name of this attribute. If Node.localName is different from null, this attribute is a qualified name.
ownerElement of type Element, readonly, introduced in DOM Level 2 The Element node this attribute is attached to or null if this attribute is not in use.
schemaTypeInfo of type TypeInfo, readonly, introduced in DOM Level 3 The type information associated with this attribute. While the type information contained in this attribute is guarantee to be correct after loading the document or invoking Document.normalizeDocument(), schemaTypeInfo may not be reliable if the node was moved.
specified of type boolean, readonly True if this attribute was explicitly given a value in the instance document, false otherwise. If the application changed the value of this attribute node (even if it ends up having the same value as the default value) then it is set to true. The implementation may handle attributes with default values from other schemas similarly but applications should use Document.normalizeDocument() to guarantee this information is up-to-date.
value of type DOMString On retrieval, the value of the attribute is returned as a string. Character and general entity references are replaced with their values. See also the method getAttribute on the Element interface.
On setting, this creates a Text node with the unparsed contents of the string, i.e. any characters that an XML processor would recognize as markup are instead treated as literal text. See also the method Element.setAttribute().
Some specialized implementations, such as some [SVG 1.1] implementations, may do normalization automatically, even after mutation; in such case, the value on retrieval may differ from the value on setting.
Interface Element

The Element interface represents an element in an HTML or XML document. Elements may have attributes associated with them; since the Element interface inherits from Node, the generic Node interface attribute attributes may be used to retrieve the set of all attributes for an element. There are methods on the Element interface to retrieve either an Attr object by name or an attribute value by name. In XML, where an attribute value may contain entity references, an Attr object should be retrieved to examine the possibly fairly complex sub-tree representing the attribute value. On the other hand, in HTML, where all attributes have simple string values, methods to directly access an attribute value can safely be used as a convenience.

Note: In DOM Level 2, the method normalize is inherited from the Node interface where it was moved.

IDL Definition
Attributes schemaTypeInfo of type TypeInfo, readonly, introduced in DOM Level 3 The type information associated with this element.
tagName of type DOMString, readonly The name of the element. If Node.localName is different from null, this attribute is a qualified name. For example, in: tagName has the value "elementExample". Note that this is case-preserving in XML, as are all of the operations of the DOM. The HTML DOM returns the tagName of an HTML element in the canonical uppercase form, regardless of the case in the source HTML document.
Methods getAttribute getAttributeNS introduced in DOM Level 2 getAttributeNode getAttributeNodeNS introduced in DOM Level 2 getElementsByTagName getElementsByTagNameNS introduced in DOM Level 2 hasAttribute introduced in DOM Level 2 hasAttributeNS introduced in DOM Level 2 removeAttribute removeAttributeNS introduced in DOM Level 2 removeAttributeNode setAttribute setAttributeNS introduced in DOM Level 2 setAttributeNode setAttributeNodeNS introduced in DOM Level 2 setIdAttribute introduced in DOM Level 3 setIdAttributeNS introduced in DOM Level 3 setIdAttributeNode introduced in DOM Level 3 Interface Text

The Text interface inherits from CharacterData and represents the textual content (termed character data in XML) of an Element or Attr. If there is no markup inside an element's content, the text is contained in a single object implementing the Text interface that is the only child of the element. If there is markup, it is parsed into the information items (elements, comments, etc.) and Text nodes that form the list of children of the element.

When a document is first made available via the DOM, there is only one Text node for each block of text. Users may create adjacent Text nodes that represent the contents of a given element without any intervening markup, but should be aware that there is no way to represent the separations between these nodes in XML or HTML, so they will not (in general) persist between DOM editing sessions. The Node.normalize() method merges any such adjacent Text objects into a single node for each block of text.

No lexical check is done on the content of a Text node and, depending on its position in the document, some characters must be escaped during serialization using character references; e.g. the characters "<&" if the textual content is part of an element or of an attribute, the character sequence "]]>" when part of an element, the quotation mark character " or the apostrophe character ' when part of an attribute.
IDL Definition

Attributes isElementContentWhitespace of type boolean, readonly, introduced in DOM Level 3 Returns whether this text node contains element content whitespace, often abusively called "ignorable whitespace". The text node is determined to contain whitespace in element content during the load of the document or if validation occurs while using Document.normalizeDocument().
wholeText of type DOMString, readonly, introduced in DOM Level 3 Returns all text of Text nodes logically-adjacent text nodes to this node, concatenated in document order.
For instance, in the example below wholeText on the Text node that contains "bar" returns "barfoo", while on the Text node that contains "foo" it returns "barfoo". Methods replaceWholeText introduced in DOM Level 3 splitText Interface Comment

This interface inherits from CharacterData and represents the content of a comment, i.e., all the characters between the starting '<!--' and ending '-->'. Note that this is the definition of a comment in XML, and, in practice, HTML, although some HTML tools may implement the full SGML comment structure.

No lexical check is done on the content of a comment and it is therefore possible to have the character sequence "--" (double-hyphen) in the content, which is illegal in a comment per section 2.5 of [XML 1.0]. The presence of this character sequence must generate a fatal error during serialization.
IDL Definition

Interface TypeInfo (introduced in DOM Level 3)

The TypeInfo interface represents a type referenced from Element or Attr nodes, specified in the schemas associated with the document. The type is a pair of a namespace URI and name properties, and depends on the document's schema.

If the document's schema is an XML DTD [XML 1.0], the values are computed as follows:

• If this type is referenced from an Attr node, typeNamespace is "http://www.w3.org/TR/REC-xml" and typeName represents the [attribute type] property in the [XML Information Set]. If there is no declaration for the attribute, typeNamespace and typeName are null.
• If this type is referenced from an Element node, typeNamespace and typeName are null.

If the document's schema is an XML Schema [XML Schema Part 1], the values are computed as follows using the post-schema-validation infoset contributions (also called PSVI contributions):

• If the [validity] property exists AND is "invalid" or "notKnown": the {target namespace} and {name} properties of the declared type if available, otherwise null.

  Note: At the time of writing, the XML Schema specification does not require exposing the declared type. Thus, DOM implementations might choose not to provide type information if validity is not valid.

• If the [validity] property exists and is "valid":
  1. If [member type definition] exists:
     1. If {name} is not absent, then expose {name} and {target namespace} properties of the [member type definition] property;
     2. Otherwise, expose the namespace and local name of the corresponding anonymous type name.
  2. If the [type definition] property exists:
     1. If {name} is not absent, then expose {name} and {target namespace} properties of the [type definition] property;
     2. Otherwise, expose the namespace and local name of the corresponding anonymous type name.
  3. If the [member type definition anonymous] exists:
     1. If it is false, then expose [member type definition name] and [member type definition namespace] properties;
     2. Otherwise, expose the namespace and local name of the corresponding anonymous type name.
  4. If the [type definition anonymous] exists:
     1. If it is false, then expose [type definition name] and [type definition namespace] properties;
     2. Otherwise, expose the namespace and local name of the corresponding anonymous type name.

Note: Other schema languages are outside the scope of the W3C and therefore should define how to represent their type systems using TypeInfo.

IDL Definition
Definition group DerivationMethods

These are the available values for the derivationMethod parameter used by the method TypeInfo.isDerivedFrom(). It is a set of possible types of derivation, and the values represent bit positions. If a bit in the derivationMethod parameter is set to 1, the corresponding type of derivation will be taken into account when evaluating the derivation between the reference type definition and the other type definition. When using the isDerivedFrom method, combining all of them in the derivationMethod parameter is equivalent to invoking the method for each of them separately and combining the results with the OR boolean function. This specification only defines the type of derivation for XML Schema.

In addition to the types of derivation listed below, please note that:

• any type derives from xsd:anyType.
• any simple type derives from xsd:anySimpleType by restriction.
• any complex type does not derive from xsd:anySimpleType by restriction.

Defined Constants DERIVATION_EXTENSION If the document's schema is an XML Schema [XML Schema Part 1], this constant represents the derivation by extension.
The reference type definition is derived by extension from the other type definition if the other type definition can be reached recursively following the {base type definition} property from the reference type definition, and at least one of the derivation methods involved is an extension. DERIVATION_LIST If the document's schema is an XML Schema [XML Schema Part 1], this constant represents the list.
The reference type definition is derived by list from the other type definition if there exists two type definitions T1 and T2 such as the reference type definition is derived from T1 by DERIVATION_RESTRICTION or DERIVATION_EXTENSION, T2 is derived from the other type definition by DERIVATION_RESTRICTION, T1 has {variety} list, and T2 is the {item type definition}. Note that T1 could be the same as the reference type definition, and T2 could be the same as the other type definition. DERIVATION_RESTRICTION If the document's schema is an XML Schema [XML Schema Part 1], this constant represents the derivation by restriction if complex types are involved, or a restriction if simple types are involved.
The reference type definition is derived by restriction from the other type definition if the other type definition is the same as the reference type definition, or if the other type definition can be reached recursively following the {base type definition} property from the reference type definition, and all the derivation methods involved are restriction. DERIVATION_UNION If the document's schema is an XML Schema [XML Schema Part 1], this constant represents the union if simple types are involved.
The reference type definition is derived by union from the other type definition if there exists two type definitions T1 and T2 such as the reference type definition is derived from T1 by DERIVATION_RESTRICTION or DERIVATION_EXTENSION, T2 is derived from the other type definition by DERIVATION_RESTRICTION, T1 has {variety} union, and one of the {member type definitions} is T2. Note that T1 could be the same as the reference type definition, and T2 could be the same as the other type definition. Attributes typeName of type DOMString, readonly The name of a type declared for the associated element or attribute, or null if unknown.
typeNamespace of type DOMString, readonly The namespace of the type declared for the associated element or attribute or null if the element does not have declaration or if no namespace information is available.
Methods isDerivedFrom Interface UserDataHandler (introduced in DOM Level 3)

When associating an object to a key on a node using Node.setUserData() the application can provide a handler that gets called when the node the object is associated to is being cloned, imported, or renamed. This can be used by the application to implement various behaviors regarding the data it associates to the DOM nodes. This interface defines that handler.
IDL Definition

Definition group OperationType

An integer indicating the type of operation being performed on a node. Defined Constants NODE_ADOPTED The node is adopted, using Document.adoptNode(). NODE_CLONED The node is cloned, using Node.cloneNode(). NODE_DELETED The node is deleted.

Note: This may not be supported or may not be reliable in certain environments, such as Java, where the implementation has no real control over when objects are actually deleted.

NODE_IMPORTED The node is imported, using Document.importNode(). NODE_RENAMED The node is renamed, using Document.renameNode(). Methods handle Interface DOMError (introduced in DOM Level 3)

DOMError is an interface that describes an error.
IDL Definition

Definition group ErrorSeverity

An integer indicating the severity of the error. Defined Constants SEVERITY_ERROR The severity of the error described by the DOMError is error. A SEVERITY_ERROR may not cause the processing to stop if the error can be recovered, unless DOMErrorHandler.handleError() returns false. SEVERITY_FATAL_ERROR The severity of the error described by the DOMError is fatal error. A SEVERITY_FATAL_ERROR will cause the normal processing to stop. The return value of DOMErrorHandler.handleError() is ignored unless the implementation chooses to continue, in which case the behavior becomes undefined. SEVERITY_WARNING The severity of the error described by the DOMError is warning. A SEVERITY_WARNING will not cause the processing to stop, unless DOMErrorHandler.handleError() returns false. Attributes location of type DOMLocator, readonly The location of the error.
message of type DOMString, readonly An implementation specific string describing the error that occurred.
relatedData of type DOMObject, readonly The related DOMError.type dependent data if any.
relatedException of type DOMObject, readonly The related platform dependent exception if any.
severity of type unsigned short, readonly The severity of the error, either SEVERITY_WARNING, SEVERITY_ERROR, or SEVERITY_FATAL_ERROR.
type of type DOMString, readonly A DOMString indicating which related data is expected in relatedData. Users should refer to the specification of the error in order to find its DOMString type and relatedData definitions if any.

Note: As an example, Document.normalizeDocument() does generate warnings when the "split-cdata-sections" parameter is in use. Therefore, the method generates a SEVERITY_WARNING with type "cdata-sections-splitted" and the first CDATASection node in document order resulting from the split is returned by the relatedData attribute.

Interface DOMErrorHandler (introduced in DOM Level 3)

DOMErrorHandler is a callback interface that the DOM implementation can call when reporting errors that happens while processing XML data, or when doing some other processing (e.g. validating a document). A DOMErrorHandler object can be attached to a Document using the "error-handler" on the DOMConfiguration interface. If more than one error needs to be reported during an operation, the sequence and numbers of the errors passed to the error handler are implementation dependent.

The application that is using the DOM implementation is expected to implement this interface.
IDL Definition

Methods handleError Interface DOMLocator (introduced in DOM Level 3)

DOMLocator is an interface that describes a location (e.g. where an error occurred).
IDL Definition

Attributes byteOffset of type long, readonly The byte offset into the input source this locator is pointing to or -1 if there is no byte offset available.
columnNumber of type long, readonly The column number this locator is pointing to, or -1 if there is no column number available.
lineNumber of type long, readonly The line number this locator is pointing to, or -1 if there is no column number available.
relatedNode of type Node, readonly The node this locator is pointing to, or null if no node is available.
uri of type DOMString, readonly The URI this locator is pointing to, or null if no URI is available.
utf16Offset of type long, readonly The UTF-16, as defined in [Unicode] and Amendment 1 of [ISO/IEC 10646], offset into the input source this locator is pointing to or -1 if there is no UTF-16 offset available.
Interface DOMConfiguration (introduced in DOM Level 3)

The DOMConfiguration interface represents the configuration of a document and maintains a table of recognized parameters. Using the configuration, it is possible to change Document.normalizeDocument() behavior, such as replacing the CDATASection nodes with Text nodes or specifying the type of the schema that must be used when the validation of the Document is requested. DOMConfiguration objects are also used in [DOM Level 3 Load and Save] in the DOMParser and DOMSerializer interfaces.

The parameter names used by the DOMConfiguration object are defined throughout the DOM Level 3 specifications. Names are case-insensitive. To avoid possible conflicts, as a convention, names referring to parameters defined outside the DOM specification should be made unique. Because parameters are exposed as properties in the ECMAScript Language Binding, names are recommended to follow the section "5.16 Identifiers" of [Unicode] with the addition of the character '-' (HYPHEN-MINUS) but it is not enforced by the DOM implementation. DOM Level 3 Core Implementations are required to recognize all parameters defined in this specification. Some parameter values may also be required to be supported by the implementation. Refer to the definition of the parameter to know if a value must be supported or not.

Note: Parameters are similar to features and properties used in SAX2 [SAX].

The following list of parameters defined in the DOM: "canonical-form" true [optional]
Canonicalize the document according to the rules specified in [Canonical XML], such as removing the DocumentType node (if any) from the tree, or removing superfluous namespace declarations from each element. Note that this is limited to what can be represented in the DOM; in particular, there is no way to specify the order of the attributes in the DOM. In addition,
Setting this parameter to true will also set the state of the parameters listed below. Later changes to the state of one of those parameters will revert "canonical-form" back to false.
Parameters set to false: "entities", "normalize-characters", "cdata-sections".
Parameters set to true: "namespaces", "namespace-declarations", "well-formed", "element-content-whitespace".
Other parameters are not changed unless explicitly specified in the description of the parameters.false [required] (default)
Do not canonicalize the document. "cdata-sections" true [required] (default)
Keep CDATASection nodes in the document.false [required]
Transform CDATASection nodes in the document into Text nodes. The new Text node is then combined with any adjacent Text node. "check-character-normalization" true [optional]
Check if the characters in the document are fully normalized, as defined in appendix B of [XML 1.1]. When a sequence of characters is encountered that fails normalization checking, an error with the DOMError.type equals to "check-character-normalization-failure" is issued. false [required] (default)
Do not check if characters are normalized. "comments" true [required] (default)
Keep Comment nodes in the document.false [required]
Discard Comment nodes in the document. "datatype-normalization" true [optional]
Expose schema normalized values in the tree, such as XML Schema normalized values in the case of XML Schema. Since this parameter requires to have schema information, the "validate" parameter will also be set to true. Having this parameter activated when "validate" is false has no effect and no schema-normalization will happen.

Note: Since the document contains the result of the XML 1.0 processing, this parameter does not apply to attribute value normalization as defined in section 3.3.3 of [XML 1.0] and is only meant for schema languages other than Document Type Definition (DTD).

false [required] (default)
Do not perform schema normalization on the tree. "element-content-whitespace" true [required] (default)
Keep all whitespaces in the document.false [optional]
Discard all Text nodes that contain whitespaces in element content, as described in [element content whitespace]. The implementation is expected to use the attribute Text.isElementContentWhitespace to determine if a Text node should be discarded or not. "entities" true [required] (default)
Keep EntityReference nodes in the document.false [required]
Remove all EntityReference nodes from the document, putting the entity expansions directly in their place. Text nodes are normalized, as defined in Node.normalize. Only unexpanded entity references are kept in the document.

Note: This parameter does not affect Entity nodes.

"error-handler" [required]
Contains a DOMErrorHandler object. If an error is encountered in the document, the implementation will call back the DOMErrorHandler registered using this parameter. The implementation may provide a default DOMErrorHandler object.
When called, DOMError.relatedData will contain the closest node to where the error occurred. If the implementation is unable to determine the node where the error occurs, DOMError.relatedData will contain the Document node. Mutations to the document from within an error handler will result in implementation dependent behavior. "infoset" true [required]
Keep in the document the information defined in the XML Information Set [XML Information Set].
This forces the following parameters to false: "validate-if-schema", "entities", "datatype-normalization", "cdata-sections".
This forces the following parameters to true: "namespace-declarations", "well-formed", "element-content-whitespace", "comments", "namespaces".
Other parameters are not changed unless explicitly specified in the description of the parameters.
Note that querying this parameter with getParameter returns true only if the individual parameters specified above are appropriately set.false Setting infoset to false has no effect. "namespaces" true [required] (default)
Perform the namespace processing as defined in Namespace Normalization. false [optional]
Do not perform the namespace processing. "namespace-declarations" This parameter has no effect if the parameter "namespaces" is set to false. true [required] (default)
Include namespace declaration attributes, specified or defaulted from the schema, in the document. See also the sections "Declaring Namespaces" in [XML Namespaces] and [XML Namespaces 1.1].false [required]
Discard all namespace declaration attributes. The namespace prefixes (Node.prefix) are retained even if this parameter is set to false. "normalize-characters" true [optional]
Fully normalized the characters in the document as defined in appendix B of [XML 1.1]. false [required] (default)
Do not perform character normalization. "schema-location" [optional]
Represent a DOMString object containing a list of URIs, separated by whitespaces (characters matching the nonterminal production S defined in section 2.3 [XML 1.0]), that represents the schemas against which validation should occur, i.e. the current schema. The types of schemas referenced in this list must match the type specified with schema-type, otherwise the behavior of an implementation is undefined.
The schemas specified using this property take precedence to the schema information specified in the document itself. For namespace aware schema, if a schema specified using this property and a schema specified in the document instance (i.e. using the schemaLocation attribute) in a schema document (i.e. using schema import mechanisms) share the same targetNamespace, the schema specified by the user using this property will be used. If two schemas specified using this property share the same targetNamespace or have no namespace, the behavior is implementation dependent.
If no location has been provided, this parameter is null.

Note: The "schema-location" parameter is ignored unless the "schema-type" parameter value is set. It is strongly recommended that Document.documentURI will be set so that an implementation can successfully resolve any external entities referenced.

"schema-type" [optional]
Represent a DOMString object containing an absolute URI and representing the type of the schema language used to validate a document against. Note that no lexical checking is done on the absolute URI.
If this parameter is not set, a default value may be provided by the implementation, based on the schema languages supported and on the schema language used at load time. If no value is provided, this parameter is null.

Note: For XML Schema [XML Schema Part 1], applications must use the value "http://www.w3.org/2001/XMLSchema". For XML DTD [XML 1.0], applications must use the value "http://www.w3.org/TR/REC-xml". Other schema languages are outside the scope of the W3C and therefore should recommend an absolute URI in order to use this method.

"split-cdata-sections" true [required] (default)
Split CDATA sections containing the CDATA section termination marker ']]>'. When a CDATA section is split a warning is issued with a DOMError.type equals to "cdata-sections-splitted" and DOMError.relatedData equals to the first CDATASection node in document order resulting from the split.false [required]
Signal an error if a CDATASection contains an unrepresentable character. "validate" true [optional]
Require the validation against a schema (i.e. XML schema, DTD, any other type or representation of schema) of the document as it is being normalized as defined by [XML 1.0]. If validation errors are found, or no schema was found, the error handler is notified. Schema-normalized values will not be exposed according to the schema in used unless the parameter "datatype-normalization" is true.
This parameter will reevaluate:

• Attribute nodes with Attr.specified equals to false, as specified in the description of the Attr interface;
• The value of the attribute Text.isElementContentWhitespace for all Text nodes;
• The value of the attribute Attr.isId for all Attr nodes;
• The attributes Element.schemaTypeInfo and Attr.schemaTypeInfo.

Note: "validate-if-schema" and "validate" are mutually exclusive, setting one of them to true will set the other one to false. Applications should also consider setting the parameter "well-formed" to true, which is the default for that option, when validating the document.

false [required] (default)
Do not accomplish schema processing, including the internal subset processing. Default attribute values information are kept. Note that validation might still happen if "validate-if-schema" is true. "validate-if-schema" true [optional]
Enable validation only if a declaration for the document element can be found in a schema (independently of where it is found, i.e. XML schema, DTD, or any other type or representation of schema). If validation is enabled, this parameter has the same behavior as the parameter "validate" set to true.

Note: "validate-if-schema" and "validate" are mutually exclusive, setting one of them to true will set the other one to false.

false [required] (default)
No schema processing should be performed if the document has a schema, including internal subset processing. Default attribute values information are kept. Note that validation must still happen if "validate" is true. "well-formed" true [required] (default)
Check if all nodes are XML well formed according to the XML version in use in Document.xmlVersion:

• check if the attribute Node.nodeName contains invalid characters according to its node type and generate a DOMError of type "wf-invalid-character-in-node-name", with a DOMError.SEVERITY_ERROR severity, if necessary;
• check if the text content inside Attr, Element, Comment, Text, CDATASection nodes for invalid characters and generate a DOMError of type "wf-invalid-character", with a DOMError.SEVERITY_ERROR severity, if necessary;
• check if the data inside ProcessingInstruction nodes for invalid characters and generate a DOMError of type "wf-invalid-character", with a DOMError.SEVERITY_ERROR severity, if necessary;

false [optional]
Do not check for XML well-formedness.

The resolution of the system identifiers associated with entities is done using Document.documentURI. However, when the feature "LS" defined in [DOM Level 3 Load and Save] is supported by the DOM implementation, the parameter "resource-resolver" can also be used on DOMConfiguration objects attached to Document nodes. If this parameter is set, Document.normalizeDocument() will invoke the resource resolver instead of using Document.documentURI.
IDL Definition

Attributes parameterNames of type DOMStringList, readonly The list of the parameters supported by this DOMConfiguration object and for which at least one value can be set by the application. Note that this list can also contain parameter names defined outside this specification.
Methods canSetParameter getParameter setParameter

1.5 Extended Interfaces: XML Module

The interfaces defined here form part of the DOM Core specification, but objects that expose these interfaces will never be encountered in a DOM implementation that deals only with HTML.

The interfaces found within this section are not mandatory. A DOM application may use the DOMImplementation.hasFeature(feature, version) method with parameter values "XML" and "3.0" (respectively) to determine whether or not this module is supported by the implementation. In order to fully support this module, an implementation must also support the "Core" feature defined in Fundamental Interfaces: Core Module and the feature "XMLVersion" with version "1.0" defined in Document.xmlVersion. Please refer to additional information about Conformance in this specification. The DOM Level 3 XML module is backward compatible with the DOM Level 2 XML [DOM Level 2 Core] and DOM Level 1 XML [DOM Level 1] modules, i.e. a DOM Level 3 XML implementation who returns true for "XML" with the version number "3.0" must also return true for this feature when the version number is "2.0", "1.0", "" or, null. Interface CDATASection

CDATA sections are used to escape blocks of text containing characters that would otherwise be regarded as markup. The only delimiter that is recognized in a CDATA section is the "]]>" string that ends the CDATA section. CDATA sections cannot be nested. Their primary purpose is for including material such as XML fragments, without needing to escape all the delimiters.

The CharacterData.data attribute holds the text that is contained by the CDATA section. Note that this may contain characters that need to be escaped outside of CDATA sections and that, depending on the character encoding ("charset") chosen for serialization, it may be impossible to write out some characters as part of a CDATA section.

The CDATASection interface inherits from the CharacterData interface through the Text interface. Adjacent CDATASection nodes are not merged by use of the normalize method of the Node interface.

No lexical check is done on the content of a CDATA section and it is therefore possible to have the character sequence "]]>" in the content, which is illegal in a CDATA section per section 2.7 of [XML 1.0]. The presence of this character sequence must generate a fatal error during serialization or the cdata section must be splitted before the serialization (see also the parameter "split-cdata-sections" in the DOMConfiguration interface).

Note: Because no markup is recognized within a CDATASection, character numeric references cannot be used as an escape mechanism when serializing. Therefore, action needs to be taken when serializing a CDATASection with a character encoding where some of the contained characters cannot be represented. Failure to do so would not produce well-formed XML.
One potential solution in the serialization process is to end the CDATA section before the character, output the character using a character reference or entity reference, and open a new CDATA section for any further characters in the text node. Note, however, that some code conversion libraries at the time of writing do not return an error or exception when a character is missing from the encoding, making the task of ensuring that data is not corrupted on serialization more difficult.

IDL Definition
Interface DocumentType

Each Document has a doctype attribute whose value is either null or a DocumentType object. The DocumentType interface in the DOM Core provides an interface to the list of entities that are defined for the document, and little else because the effect of namespaces and the various XML schema efforts on DTD representation are not clearly understood as of this writing.

DOM Level 3 doesn't support editing DocumentType nodes. DocumentType nodes are read-only.
IDL Definition

Attributes entities of type NamedNodeMap, readonly A NamedNodeMap containing the general entities, both external and internal, declared in the DTD. Parameter entities are not contained. Duplicates are discarded. For example in: the interface provides access to foo and the first declaration of bar but not the second declaration of bar or baz. Every node in this map also implements the Entity interface.
The DOM Level 2 does not support editing entities, therefore entities cannot be altered in any way.
internalSubset of type DOMString, readonly, introduced in DOM Level 2 The internal subset as a string, or null if there is none. This is does not contain the delimiting square brackets.

Note: The actual content returned depends on how much information is available to the implementation. This may vary depending on various parameters, including the XML processor used to build the document.

name of type DOMString, readonly The name of DTD; i.e., the name immediately following the DOCTYPE keyword.
notations of type NamedNodeMap, readonly A NamedNodeMap containing the notations declared in the DTD. Duplicates are discarded. Every node in this map also implements the Notation interface.
The DOM Level 2 does not support editing notations, therefore notations cannot be altered in any way.
publicId of type DOMString, readonly, introduced in DOM Level 2 The public identifier of the external subset.
systemId of type DOMString, readonly, introduced in DOM Level 2 The system identifier of the external subset. This may be an absolute URI or not.
Interface Notation

This interface represents a notation declared in the DTD. A notation either declares, by name, the format of an unparsed entity (see section 4.7 of the XML 1.0 specification [XML 1.0]), or is used for formal declaration of processing instruction targets (see section 2.6 of the XML 1.0 specification [XML 1.0]). The nodeName attribute inherited from Node is set to the declared name of the notation.

The DOM Core does not support editing Notation nodes; they are therefore readonly.

A Notation node does not have any parent.
IDL Definition

Attributes publicId of type DOMString, readonly The public identifier of this notation. If the public identifier was not specified, this is null.
systemId of type DOMString, readonly The system identifier of this notation. If the system identifier was not specified, this is null. This may be an absolute URI or not.
Interface Entity

This interface represents a known entity, either parsed or unparsed, in an XML document. Note that this models the entity itself not the entity declaration.

The nodeName attribute that is inherited from Node contains the name of the entity.

An XML processor may choose to completely expand entities before the structure model is passed to the DOM; in this case there will be no EntityReference nodes in the document tree.

XML does not mandate that a non-validating XML processor read and process entity declarations made in the external subset or declared in parameter entities. This means that parsed entities declared in the external subset need not be expanded by some classes of applications, and that the replacement text of the entity may not be available. When the replacement text is available, the corresponding Entity node's child list represents the structure of that replacement value. Otherwise, the child list is empty.

DOM Level 3 does not support editing Entity nodes; if a user wants to make changes to the contents of an Entity, every related EntityReference node has to be replaced in the structure model by a clone of the Entity's contents, and then the desired changes must be made to each of those clones instead. Entity nodes and all their descendants are readonly.

An Entity node does not have any parent.

Note: If the entity contains an unbound namespace prefix, the namespaceURI of the corresponding node in the Entity node subtree is null. The same is true for EntityReference nodes that refer to this entity, when they are created using the createEntityReference method of the Document interface.

IDL Definition
Attributes inputEncoding of type DOMString, readonly, introduced in DOM Level 3 An attribute specifying the encoding used for this entity at the time of parsing, when it is an external parsed entity. This is null if it an entity from the internal subset or if it is not known.
notationName of type DOMString, readonly For unparsed entities, the name of the notation for the entity. For parsed entities, this is null.
publicId of type DOMString, readonly The public identifier associated with the entity if specified, and null otherwise.
systemId of type DOMString, readonly The system identifier associated with the entity if specified, and null otherwise. This may be an absolute URI or not.
xmlEncoding of type DOMString, readonly, introduced in DOM Level 3 An attribute specifying, as part of the text declaration, the encoding of this entity, when it is an external parsed entity. This is null otherwise.
xmlVersion of type DOMString, readonly, introduced in DOM Level 3 An attribute specifying, as part of the text declaration, the version number of this entity, when it is an external parsed entity. This is null otherwise.
Interface EntityReference

EntityReference nodes may be used to represent an entity reference in the tree. Note that character references and references to predefined entities are considered to be expanded by the HTML or XML processor so that characters are represented by their Unicode equivalent rather than by an entity reference. Moreover, the XML processor may completely expand references to entities while building the Document, instead of providing EntityReference nodes. If it does provide such nodes, then for an EntityReference node that represents a reference to a known entity an Entity exists, and the subtree of the EntityReference node is a copy of the Entity node subtree. However, the latter may not be true when an entity contains an unbound namespace prefix. In such a case, because the namespace prefix resolution depends on where the entity reference is, the descendants of the EntityReference node may be bound to different namespace URIs. When an EntityReference node represents a reference to an unknown entity, the node has no children and its replacement value, when used by Attr.value for example, is empty.

As for Entity nodes, EntityReference nodes and all their descendants are readonly.

Note: EntityReference nodes may cause element content and attribute value normalization problems when, such as in XML 1.0 and XML Schema, the normalization is performed after entity reference are expanded.

IDL Definition
Interface ProcessingInstruction

The ProcessingInstruction interface represents a "processing instruction", used in XML as a way to keep processor-specific information in the text of the document.

No lexical check is done on the content of a processing instruction and it is therefore possible to have the character sequence "?>" in the content, which is illegal a processing instruction per section 2.6 of [XML 1.0]. The presence of this character sequence must generate a fatal error during serialization.
IDL Definition

Attributes data of type DOMString The content of this processing instruction. This is from the first non white space character after the target to the character immediately preceding the ?>.
target of type DOMString, readonly The target of this processing instruction. XML defines this as being the first token following the markup that begins the processing instruction.