[W3C]
Document Object Model (DOM) Level 3 Core Specification
Version 1.0
W3C Working Draft 09 June 2003
This version:
http://www.w3.org/TR/2003/WD-DOM-Level-3-Core-20030609
Latest version:
http://www.w3.org/TR/DOM-Level-3-Core
Previous version:
http://www.w3.org/TR/2003/WD-DOM-Level-3-Core-20030226
Editors:
Arnaud Le Hors, IBM
Philippe Le Hégaret, W3C
Lauren Wood, SoftQuad, Inc. (WG Chair emerita, for DOM Level 1 and 2)
Gavin Nicol, Inso EPS (for DOM Level 1)
Jonathan Robie, Texcel Research and Software AG (for DOM Level 1)
Mike Champion, ArborText and Software AG (for DOM Level 1 from November
20, 1997)
Steve Byrne, JavaSoft (for DOM Level 1 until November 19, 1997)
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Abstract
This specification defines the Document Object Model Core Level 3, a
platform- and language-neutral interface that allows programs and scripts to
dynamically access and update the content, structure and style of documents.
The Document Object Model Core Level 3 builds on the Document Object Model
Core Level 2 [DOM Level 2 Core].
Status of this document
This section describes the status of this document at the time of its
publication. Other documents may supersede this document. The latest status
of this document series is maintained at the W3C.
This document contains the Document Object Model Level 3 Core specification
and is a Last Call Working Draft for review by W3C members and other
interested parties. Comments on this document are on 31 July 2003 and are to
be sent to the public mailing list www-dom@w3.org. An archive is available
at http://lists.w3.org/Archives/Public/www-dom/.
It is a draft document and may be updated, replaced or obsoleted by other
documents at any time. It is inappropriate to use W3C Working Drafts as
reference material or to cite them as other than "work in progress". This is
work in progress and does not imply endorsement by, or the consensus of,
either W3C or members of the DOM Working Group.
This document has been produced as part of the W3C DOM Activity. The authors
of this document are the DOM Working Group members.
Patent disclosures relevant to this specification may be found on the
Working Group's patent disclosure page.
A list of current W3C Recommendations and other technical documents can be
found at http://www.w3.org/TR.
Table of contents
* Expanded Table of Contents
* W3C Copyright Notices and Licenses
* What is the Document Object Model?
* 1. Document Object Model Core
* Appendix A: Changes
* Appendix B: Namespaces Algorithms
* Appendix C: Infoset mapping
* Appendix D: Configuration Settings
* Appendix E: Accessing code point boundaries
* Appendix F: IDL Definitions
* Appendix G: Java Language Binding
* Appendix H: ECMAScript Language Binding
* Appendix I: Acknowledgements
* Glossary
* References
* Index
09 June 2003
Expanded Table of Contents
* Expanded Table of Contents
* W3C Copyright Notices and Licenses
o W3C® Document Copyright Notice and License
o W3C® Software Copyright Notice and License
o W3C® Short Software Notice
* What is the Document Object Model?
o Introduction
o What the Document Object Model is
o What the Document Object Model is not
o Where the Document Object Model came from
o Entities and the DOM Core
o DOM Architecture
o Conformance
o DOM Interfaces and DOM Implementations
* 1 Document Object Model Core
o 1.1 Overview of the DOM Core Interfaces
+ 1.1.1 The DOM Structure Model
+ 1.1.2 Memory Management
+ 1.1.3 Naming Conventions
+ 1.1.4 Inheritance vs. Flattened Views of the API
o 1.2 Primitive types
+ 1.2.1 The DOMString type
+ 1.2.2 The DOMTimeStamp type
+ 1.2.3 The DOMUserData type
+ 1.2.4 The DOMObject type
o 1.3 General considerations
+ 1.3.1 String comparisons in the DOM
+ 1.3.2 DOM URIs
+ 1.3.3 XML Namespaces
+ 1.3.4 Base URIs
+ 1.3.5 Mixed DOM implementations
+ 1.3.6 DOM Features
+ 1.3.7 Bootstrapping
o 1.4 Fundamental Interfaces: Core module
o 1.5 Extended Interfaces: XML module
* Appendix A: Changes
o A.1 New sections
o A.2 Changes to DOM Level 2 Core interfaces and exceptions
o A.3 New types
o A.4 New interfaces
* Appendix B: Namespaces Algorithms
o B.1 Namespace normalization
+ B.1.1 Scope of a binding
+ B.1.2 Conflicting namespace declaration
o B.2 Namespace Prefix Lookup
o B.3 Default Namespace Lookup
o B.4 Namespace URI Lookup
* Appendix C: Infoset mapping
o C.1 Document node mapping
+ C.1.1 Infoset to Document node
+ C.1.2 Document node to Infoset
o C.2 Element node mapping
+ C.2.1 Infoset to Element node
+ C.2.2 Element node to Infoset
o C.3 Attr node mapping
+ C.3.1 Infoset to Attr node
+ C.3.2 Attr node to Infoset
o C.4 ProcessingInstruction node mapping
+ C.4.1 Infoset to ProcessingInstruction node
+ C.4.2 ProcessingInstruction node to Infoset
o C.5 EntityReference node mapping
+ C.5.1 Infoset to EntityReference node
+ C.5.2 EntityReference node to Infoset
o C.6 Text and CDATASection nodes mapping
+ C.6.1 Infoset to Text node
+ C.6.2 Text and CDATASection nodes to Infoset
o C.7 Comment node mapping
+ C.7.1 Infoset to Comment node
+ C.7.2 Comment node to Infoset
o C.8 DocumentType node mapping
+ C.8.1 Infoset to DocumentType node
+ C.8.2 DocumentType node to Infoset
o C.9 Entity node mapping
+ C.9.1 Infoset to Entity node
+ C.9.2 Entity node to Infoset
o C.10 Notation node mapping
+ C.10.1 Infoset to Notation node
+ C.10.2 Notation node to Infoset
* Appendix D: Configuration Settings
o D.1 Configuration Scenarios
* Appendix E: Accessing code point boundaries
o E.1 Introduction
o E.2 Methods
* Appendix F: IDL Definitions
* Appendix G: Java Language Binding
o G.1 Java Binding Extension
o G.2 Other Core interfaces
* Appendix H: ECMAScript Language Binding
o H.1 ECMAScript Binding Extension
o H.2 Other Core interfaces
* Appendix I: Acknowledgements
o I.1 Production Systems
* Glossary
* References
o 1 Normative references
o 2 Informative references
* Index
09 June 2003
W3C Copyright Notices and Licenses
Copyright © 2003 World Wide Web Consortium, (Massachusetts Institute of
Technology, European Research Consortium for Informatics and Mathematics,
Keio University). All Rights Reserved.
This document is published under the W3C® Document Copyright Notice and
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09 June 2003
What is the Document Object Model?
Editors:
Philippe Le Hégaret, W3C
Lauren Wood, SoftQuad Software Inc. (for DOM Level 2)
Jonathan Robie, Texcel (for DOM Level 1)
Introduction
The Document Object Model (DOM) is an application programming interface
(API) for valid HTML and well-formed XML documents. It defines the logical
structure of documents and the way a document is accessed and manipulated.
In the DOM specification, the term "document" is used in the broad sense -
increasingly, XML is being used as a way of representing many different
kinds of information that may be stored in diverse systems, and much of this
would traditionally be seen as data rather than as documents. Nevertheless,
XML presents this data as documents, and the DOM may be used to manage this
data.
With the Document Object Model, programmers can build documents, navigate
their structure, and add, modify, or delete elements and content. Anything
found in an HTML or XML document can be accessed, changed, deleted, or added
using the Document Object Model, with a few exceptions - in particular, the
DOM interfaces for the XML internal and external subsets have not yet been
specified.
As a W3C specification, one important objective for the Document Object
Model is to provide a standard programming interface that can be used in a
wide variety of environments and applications. The DOM is designed to be
used with any programming language. In order to provide a precise,
language-independent specification of the DOM interfaces, we have chosen to
define the specifications in Object Management Group (OMG) IDL [OMG IDL], as
defined in the CORBA 2.3.1 specification [CORBA]. In addition to the OMG IDL
specification, we provide language bindings for Java [Java] and ECMAScript
[ECMAScript] (an industry-standard scripting language based on JavaScript
[JavaScript] and JScript [JScript]). Because of language binding
restrictions, a mapping has to be applied between the OMG IDL and the
programming language in used. For example, while the DOM uses IDL attributes
in the definition of interfaces, Java does not allow interfaces to contain
attributes:
// example 1: removing the first child of an element using ECMAScript
mySecondTrElement.removeChild(mySecondTrElement.firstChild);
// example 2: removing the first child of an element using Java
mySecondTrElement.removeChild(mySecondTrElement.getFirstChild());
Note: OMG IDL is used only as a language-independent and
implementation-neutral way to specify interfaces. Various other IDLs could
have been used ([COM], [Java IDL], [MIDL], ...). In general, IDLs are
designed for specific computing environments. The Document Object Model can
be implemented in any computing environment, and does not require the object
binding runtimes generally associated with such IDLs.
What the Document Object Model is
The DOM is a programming API for documents. It is based on an object
structure that closely resembles the structure of the documents it models.
For instance, consider this table, taken from an XHTML document:
| Shady Grove |
Aeolian |
| Over the River, Charlie |
Dorian |
A graphical representation of the DOM of the example table, with whitespaces
in element content (often abusively called "ignorable whitespace") removed,
is:
[graphical representation of the DOM of the example table]
Figure: graphical representation of the DOM of the example table [SVG 1.0
version]
An example of DOM manipulation using ECMAScript would be:
// access the tbody element from the table element
var myTbodyElement = myTableElement.firstChild;
// access its second tr element
// The list of children starts at 0 (and not 1).
var mySecondTrElement = myTbodyElement.childNodes[1];
// remove its first td element
mySecondTrElement.removeChild(mySecondTrElement.firstChild);
// change the text content of the remaining td element
mySecondTrElement.firstChild.firstChild.data = "Peter";
In the DOM, documents have a logical structure which is very much like a
tree; to be more precise, which is like a "forest" or "grove", which can
contain more than one tree. Each document contains zero or one doctype
nodes, one document element node, and zero or more comments or processing
instructions; the document element serves as the root of the element tree
for the document. However, the DOM does not specify that documents must be
implemented as a tree or a grove, nor does it specify how the relationships
among objects be implemented. The DOM is a logical model that may be
implemented in any convenient manner. In this specification, we use the term
structure model to describe the tree-like representation of a document. We
also use the term "tree" when referring to the arrangement of those
information items which can be reached by using "tree-walking" methods;
(this does not include attributes). One important property of DOM structure
models is structural isomorphism: if any two Document Object Model
implementations are used to create a representation of the same document,
they will create the same structure model, in accordance with the XML
Information Set [XML Information set].
Note: There may be some variations depending on the parser being used to
build the DOM. For instance, the DOM may not contain white spaces in element
content if the parser discards them.
The name "Document Object Model" was chosen because it is an "object model"
in the traditional object oriented design sense: documents are modeled using
objects, and the model encompasses not only the structure of a document, but
also the behavior of a document and the objects of which it is composed. In
other words, the nodes in the above diagram do not represent a data
structure, they represent objects, which have functions and identity. As an
object model, the DOM identifies:
* the interfaces and objects used to represent and manipulate a document
* the semantics of these interfaces and objects - including both behavior
and attributes
* the relationships and collaborations among these interfaces and objects
The structure of SGML documents has traditionally been represented by an
abstract data model, not by an object model. In an abstract data model, the
model is centered around the data. In object oriented programming languages,
the data itself is encapsulated in objects that hide the data, protecting it
from direct external manipulation. The functions associated with these
objects determine how the objects may be manipulated, and they are part of
the object model.
What the Document Object Model is not
This section is designed to give a more precise understanding of the DOM by
distinguishing it from other systems that may seem to be like it.
* The Document Object Model is not a binary specification. DOM programs
written in the same language binding will be source code compatible
across platforms, but the DOM does not define any form of binary
interoperability.
* The Document Object Model is not a way of persisting objects to XML or
HTML. Instead of specifying how objects may be represented in XML, the
DOM specifies how XML and HTML documents are represented as objects, so
that they may be used in object oriented programs.
* The Document Object Model is not a set of data structures; it is an
object model that specifies interfaces. Although this document contains
diagrams showing parent/child relationships, these are logical
relationships defined by the programming interfaces, not
representations of any particular internal data structures.
* The Document Object Model does not define what information in a
document is relevant or how information in a document is structured.
For XML, this is specified by the XML Information Set [XML Information
set]. The DOM is simply an API to this information set.
* The Document Object Model, despite its name, is not a competitor to the
Component Object Model [COM]. COM, like CORBA, is a language
independent way to specify interfaces and objects; the DOM is a set of
interfaces and objects designed for managing HTML and XML documents.
The DOM may be implemented using language-independent systems like COM
or CORBA; it may also be implemented using language-specific bindings
like the Java or ECMAScript bindings specified in this document.
Where the Document Object Model came from
The DOM originated as a specification to allow JavaScript scripts and Java
programs to be portable among Web browsers. "Dynamic HTML" was the immediate
ancestor of the Document Object Model, and it was originally thought of
largely in terms of browsers. However, when the DOM Working Group was formed
at W3C, it was also joined by vendors in other domains, including HTML or
XML editors and document repositories. Several of these vendors had worked
with SGML before XML was developed; as a result, the DOM has been influenced
by SGML Groves and the HyTime standard. Some of these vendors had also
developed their own object models for documents in order to provide an API
for SGML/XML editors or document repositories, and these object models have
also influenced the DOM.
Entities and the DOM Core
In the fundamental DOM interfaces, there are no objects representing
entities. Numeric character references, and references to the pre-defined
entities in HTML and XML, are replaced by the single character that makes up
the entity's replacement. For example, in:
This is a dog & a cat
the "&" will be replaced by the character "&", and the text in the P
element will form a single continuous sequence of characters. Since numeric
character references and pre-defined entities are not recognized as such in
CDATA sections, or in the SCRIPT and STYLE elements in HTML, they are not
replaced by the single character they appear to refer to. If the example
above were enclosed in a CDATA section, the "&" would not be replaced by
"&"; neither would the be recognized as a start tag. The representation
of general entities, both internal and external, are defined within the
extended (XML) interfaces of Document Object Model Core.
Note: When a DOM representation of a document is serialized as XML or HTML
text, applications will need to check each character in text data to see if
it needs to be escaped using a numeric or pre-defined entity. Failing to do
so could result in invalid HTML or XML. Also, implementations should be
aware of the fact that serialization into a character encoding ("charset")
that does not fully cover ISO 10646 may fail if there are characters in
markup or CDATA sections that are not present in the encoding.
DOM Architecture
The DOM specifications provide a set of APIs that forms the DOM API. Each
DOM specification defines one or more modules and each module is associated
with one feature name. For example, the DOM Core specification (this
specification) defines two modules:
* The Core module, which contains the fundamental interfaces that must be
implemented by all DOM conformant implementations, is associated with
the feature name "Core";
* The XML module, which contains the interfaces that must be implemented
by all conformant XML 1.0 [XML 1.0] (and higher) DOM implementations,
is associated with the feature name "XML".
The following representation contains all DOM modules, represented using
their feature names, defined along the DOM specifications:
[A view of the DOM Architecture]
Figure: A view of the DOM Architecture [SVG 1.0 version]
A DOM implementation can then implement one (i.e. only the Core module) or
more modules depending on the host application. A Web user agent is very
likely to implement the "MouseEvents" module, while a server-side
application will have no use of this module and will probably not implement
it.
Conformance
This section explains the different levels of conformance to DOM Level 3.
DOM Level 3 consists of 16 modules. It is possible to conform to DOM Level
3, or to a DOM Level 3 module.
An implementation is DOM Level 3 conformant if it supports the Core module
defined in this document (see Fundamental Interfaces: Core module). An
implementation conforms to a DOM Level 3 module if it supports all the
interfaces for that module and the associated semantics.
Here is the complete list of DOM Level 3.0 modules and the features used by
them. Feature names are case-insensitive.
Core module
defines the feature "Core".
XML module
Defines the feature "XML".
Events module
defines the feature "Events" in [DOM Level 3 Events].
User interface Events module
defines the feature "UIEvents" in [DOM Level 3 Events].
Mouse Events module
defines the feature "MouseEvents" in [DOM Level 3 Events].
Text Events module
defines the feature "TextEvents" in [DOM Level 3 Events].
Keyboard Events module
defines the feature "KeyboardEvents" in [DOM Level 3 Events].
Mutation Events module
defines the feature "MutationEvents" in [DOM Level 3 Events].
Mutation name Events module
defines the feature "MutationNameEvents" in [DOM Level 3 Events].
HTML Events module
defines the feature "HTMLEvents" in [DOM Level 3 Events].
Load and Save module
defines the feature "LS" in [DOM Level 3 Load and Save].
Asynchronous load module
defines the feature "LS-Async" in [DOM Level 3 Load and Save].
DocumentLS module
defines the feature "DocumentLS" in [DOM Level 3 Load and Save].
ElementLS module
defines the feature "ElementLS" in [DOM Level 3 Load and Save].
Validation module
defines the feature "Validation" in [DOM Level 3 Validation].
XPath module
defines the feature "XPath" in [DOM Level 3 XPath].
A DOM implementation must not return true to the
DOMImplementation.hasFeature(feature, version) method of the
DOMImplementation interface for that feature unless the implementation
conforms to that module. The version number for all features used in DOM
Level 3.0 is "3.0".
DOM Interfaces and DOM Implementations
The DOM specifies interfaces which may be used to manage XML or HTML
documents. It is important to realize that these interfaces are an
abstraction - much like "abstract base classes" in C++, they are a means of
specifying a way to access and manipulate an application's internal
representation of a document. Interfaces do not imply a particular concrete
implementation. Each DOM application is free to maintain documents in any
convenient representation, as long as the interfaces shown in this
specification are supported. Some DOM implementations will be existing
programs that use the DOM interfaces to access software written long before
the DOM specification existed. Therefore, the DOM is designed to avoid
implementation dependencies; in particular,
1. Attributes defined in the IDL do not imply concrete objects which must
have specific data members - in the language bindings, they are
translated to a pair of get()/set() functions, not to a data member.
Read-only attributes have only a get() function in the language
bindings.
2. DOM applications may provide additional interfaces and objects not
found in this specification and still be considered DOM conformant.
3. Because we specify interfaces and not the actual objects that are to be
created, the DOM cannot know what constructors to call for an
implementation. In general, DOM users call the createX() methods on the
Document class to create document structures, and DOM implementations
create their own internal representations of these structures in their
implementations of the createX() functions.
The Level 2 interfaces were extended to provide both Level 2 and Level 3
functionality.
DOM implementations in languages other than Java or ECMAScript may choose
bindings that are appropriate and natural for their language and run time
environment. For example, some systems may need to create a Document3 class
which inherits from a Document class and contains the new methods and
attributes.
DOM Level 3 does not specify multithreading mechanisms.
09 June 2003
1. Document Object Model Core
Editors:
Arnaud Le Hors, IBM
Philippe Le Hégaret, W3C
Gavin Nicol, Inso EPS (for DOM Level 1)
Lauren Wood, SoftQuad, Inc. (for DOM Level 1)
Mike Champion, Arbortext and Software AG (for DOM Level 1 from November
20, 1997)
Steve Byrne, JavaSoft (for DOM Level 1 until November 19, 1997)
Table of contents
* 1.1 Overview of the DOM Core Interfaces
o 1.1.1 The DOM Structure Model
o 1.1.2 Memory Management
o 1.1.3 Naming Conventions
o 1.1.4 Inheritance vs. Flattened Views of the API
* 1.2 Primitive types
o 1.2.1 The DOMString type
+ DOMString
o 1.2.2 The DOMTimeStamp type
+ DOMTimeStamp
o 1.2.3 The DOMUserData type
+ DOMUserData
o 1.2.4 The DOMObject type
+ DOMObject
* 1.3 General considerations
o 1.3.1 String comparisons in the DOM
o 1.3.2 DOM URIs
o 1.3.3 XML Namespaces
o 1.3.4 Base URIs
o 1.3.5 Mixed DOM implementations
o 1.3.6 DOM Features
o 1.3.7 Bootstrapping
* 1.4 Fundamental Interfaces: Core module
o DOMException, ExceptionCode, DOMStringList, NameList,
DOMImplementationList, DOMImplementationSource, DOMImplementation,
DocumentFragment, Document, Node, NodeList, NamedNodeMap,
CharacterData, Attr, Element, Text, Comment, TypeInfo,
UserDataHandler, DOMError, DOMErrorHandler, DOMLocator,
DOMConfiguration
* 1.5 Extended Interfaces: XML module
o CDATASection, DocumentType, Notation, Entity, EntityReference,
ProcessingInstruction
This specification defines a set of objects and interfaces for accessing and
manipulating document objects. The functionality specified (the Core
functionality) is sufficient to allow software developers and web script
authors to access and manipulate parsed HTML [HTML 4.01] and XML [XML 1.0]
content inside conforming products. The DOM Core API also allows creation
and population of a Document object using only DOM API calls. A solution for
loading a Document and saving it persistently is proposed in [DOM Level 3
Load and Save].
1.1 Overview of the DOM Core Interfaces
1.1.1 The DOM Structure Model
The DOM presents documents as a hierarchy of Node objects that also
implement other, more specialized interfaces. Some types of nodes may have
child nodes of various types, and others are leaf nodes that cannot have
anything below them in the document structure. For XML and HTML, the node
types, and which node types they may have as children, are as follows:
* Document -- Element (maximum of one), ProcessingInstruction, Comment,
DocumentType (maximum of one)
* DocumentFragment -- Element, ProcessingInstruction, Comment, Text,
CDATASection, EntityReference
* DocumentType -- no children
* EntityReference -- Element, ProcessingInstruction, Comment, Text,
CDATASection, EntityReference
* Element -- Element, Text, Comment, ProcessingInstruction, CDATASection,
EntityReference
* Attr -- Text, EntityReference
* ProcessingInstruction -- no children
* Comment -- no children
* Text -- no children
* CDATASection -- no children
* Entity -- Element, ProcessingInstruction, Comment, Text, CDATASection,
EntityReference
* Notation -- no children
The DOM also specifies a NodeList interface to handle ordered lists of
Nodes, such as the children of a Node, or the elements returned by the
Element.getElementsByTagNameNS(namespaceURI, localName) method, and also a
NamedNodeMap interface to handle unordered sets of nodes referenced by their
name attribute, such as the attributes of an Element. NodeList and
NamedNodeMap objects in the DOM are live; that is, changes to the underlying
document structure are reflected in all relevant NodeList and NamedNodeMap
objects. For example, if a DOM user gets a NodeList object containing the
children of an Element, then subsequently adds more children to that element
(or removes children, or modifies them), those changes are automatically
reflected in the NodeList, without further action on the user's part.
Likewise, changes to a Node in the tree are reflected in all references to
that Node in NodeList and NamedNodeMap objects.
Finally, the interfaces Text, Comment, and CDATASection all inherit from the
CharacterData interface.
1.1.2 Memory Management
Most of the APIs defined by this specification are interfaces rather than
classes. That means that an implementation need only expose methods with the
defined names and specified operation, not implement classes that correspond
directly to the interfaces. This allows the DOM APIs to be implemented as a
thin veneer on top of legacy applications with their own data structures, or
on top of newer applications with different class hierarchies. This also
means that ordinary constructors (in the Java or C++ sense) cannot be used
to create DOM objects, since the underlying objects to be constructed may
have little relationship to the DOM interfaces. The conventional solution to
this in object-oriented design is to define factory methods that create
instances of objects that implement the various interfaces. Objects
implementing some interface "X" are created by a "createX()" method on the
Document interface; this is because all DOM objects live in the context of a
specific Document.
The Core DOM APIs are designed to be compatible with a wide range of
languages, including both general-user scripting languages and the more
challenging languages used mostly by professional programmers. Thus, the DOM
APIs need to operate across a variety of memory management philosophies,
from language bindings that do not expose memory management to the user at
all, through those (notably Java) that provide explicit constructors but
provide an automatic garbage collection mechanism to automatically reclaim
unused memory, to those (especially C/C++) that generally require the
programmer to explicitly allocate object memory, track where it is used, and
explicitly free it for re-use. To ensure a consistent API across these
platforms, the DOM does not address memory management issues at all, but
instead leaves these for the implementation. Neither of the explicit
language bindings defined by the DOM API (for ECMAScript and Java) require
any memory management methods, but DOM bindings for other languages
(especially C or C++) may require such support. These extensions will be the
responsibility of those adapting the DOM API to a specific language, not the
DOM Working Group.
1.1.3 Naming Conventions
While it would be nice to have attribute and method names that are short,
informative, internally consistent, and familiar to users of similar APIs,
the names also should not clash with the names in legacy APIs supported by
DOM implementations. Furthermore, both OMG IDL [OMG IDL] and ECMAScript
[ECMAScript] have significant limitations in their ability to disambiguate
names from different namespaces that make it difficult to avoid naming
conflicts with short, familiar names. So, DOM names tend to be long and
descriptive in order to be unique across all environments.
The Working Group has also attempted to be internally consistent in its use
of various terms, even though these may not be common distinctions in other
APIs. For example, the DOM API uses the method name "remove" when the method
changes the structural model, and the method name "delete" when the method
gets rid of something inside the structure model. The thing that is deleted
is not returned. The thing that is removed may be returned, when it makes
sense to return it.
1.1.4 Inheritance vs. Flattened Views of the API
The DOM Core APIs present two somewhat different sets of interfaces to an
XML/HTML document: one presenting an "object oriented" approach with a
hierarchy of inheritance, and a "simplified" view that allows all
manipulation to be done via the Node interface without requiring casts (in
Java and other C-like languages) or query interface calls in COM
environments. These operations are fairly expensive in Java and COM, and the
DOM may be used in performance-critical environments, so we allow
significant functionality using just the Node interface. Because many other
users will find the inheritance hierarchy easier to understand than the
"everything is a Node" approach to the DOM, we also support the full
higher-level interfaces for those who prefer a more object-oriented API.
In practice, this means that there is a certain amount of redundancy in the
API. The Working Group considers the "inheritance" approach the primary view
of the API, and the full set of functionality on Node to be "extra"
functionality that users may employ, but that does not eliminate the need
for methods on other interfaces that an object-oriented analysis would
dictate. (Of course, when the O-O analysis yields an attribute or method
that is identical to one on the Node interface, we don't specify a
completely redundant one.) Thus, even though there is a generic
Node.nodeName attribute on the Node interface, there is still a
Element.tagName attribute on the Element interface; these two attributes
must contain the same value, but the it is worthwhile to support both, given
the different constituencies the DOM API must satisfy.
1.2 Primitive types
To ensure interoperability, this specification specifies the following
primitive types used in various DOM modules. Even though the DOM uses the
primitive types in the interfaces, bindings may use different types and
normative bindings are only given for Java and ECMAScript in this
specification.
1.2.1 The DOMString type
The DOMString type is used to store [Unicode] characters as a code unit
string as defined in section 3.4 of [CharModel]. Applications must encode
the characters using UTF-16 as defined in [Unicode] and Amendment 1 of
[ISO/IEC 10646].
Type Definition DOMString
A DOMString is a sequence of 16-bit units.
IDL Definition
valuetype DOMString sequence;
The UTF-16 encoding was chosen because of its widespread industry practice.
Note that for both HTML and XML, the document character set (and therefore
the notation of numeric character references) is based on UCS [ISO/IEC
10646]. A single numeric character reference in a source document may
therefore in some cases correspond to two 16-bit units in a DOMString (a
high surrogate and a low surrogate). For issues related to string
comparisons, refer to String comparisons in the DOM.
For Java and ECMAScript, DOMString is bound to the String type because both
languages also use UTF-16 as their encoding.
Note: As of August 2000, the OMG IDL specification ([OMG IDL]) included a
wstring type. However, that definition did not meet the interoperability
criteria of the DOM API since it relied on negotiation to decide the width
and encoding of a character.
1.2.2 The DOMTimeStamp type
The DOMTimeStamp type is used to store an absolute or relative time.
Type Definition DOMTimeStamp
A DOMTimeStamp represents a number of milliseconds.
IDL Definition
typedef unsigned long long DOMTimeStamp;
For Java, DOMTimeStamp is bound to the long type. For ECMAScript,
DOMTimeStamp is bound to the Date type because the range of the integer type
is too small.
1.2.3 The DOMUserData type
The DOMUserData type is used to store an application data.
Type Definition DOMUserData
A DOMUserData represents a reference to an application data.
IDL Definition
typedef any DOMUserData;
For Java, DOMUserData is bound to the Object type. For ECMAScript,
DOMUserData is bound to any type.
1.2.4 The DOMObject type
The DOMUserData type is used to store an application object.
Type Definition DOMObject
A DOMObject represents a reference to an application object.
IDL Definition
typedef Object DOMObject;
For Java and ECMAScript, DOMObject is bound to the Object type.
1.3 General considerations
1.3.1 String comparisons in the DOM
The DOM has many interfaces that imply string matching. For XML, string
comparisons are case-sensitive and performed with a binary comparison of the
16-bit units of the DOMStrings. However, for case-insensitive markup
languages, such as HTML 4.01 or earlier, these comparisons are
case-insensitive where appropriate.
Note that HTML processors often perform specific case normalizations
(canonicalization) of the markup before the DOM structures are built. This
is typically using uppercase for element names and lowercase for attribute
names. For this reason, applications should also compare element and
attribute names returned by the DOM implementation in a case-insensitive
manner.
The character normalization, as defined in [CharModel], is assumed to happen
at serialization time. The DOM Level 3 Load and Save module [DOM Level 3
Load and Save] provides a serialization mechanism (see the DOMSerializer
interface, section 2.3.1) and uses the "normalize-characters" and
"check-character-normalization" to assure that text is fully-normalized (see
section 4.2.3 in [CharModel]. Other serialization mechanisms built on top of
the DOM Level 3 Core also have to assure that text is fully-normalized.
1.3.2 DOM URIs
The DOM specification relies on DOMString values as resource identifiers,
such that the following conditions are met:
1. A complete identifier absolutely identifies a resource on the web;
2. Simple string equality establishes equality of complete resource
identifiers, and no other equivalence of resource identifiers is
considered significant to the DOM specification;
3. An incomplete identifier is easily detected and completed relative to a
complete identifier;
4. Retrieval of content of a resource may be accomplished where required.
Within the DOM specifications, these identifiers are called URIs, "Universal
Resource Identifiers", but this is meant abstractly. The DOM implementation
does not necessarily process its URIs according to the URI specification
[IETF RFC 2396].
Generally the particular form of these identifiers must be ignored.
When is not possible to completely ignore the type of any DOM URI, either
because an incomplete identifier must be completed or because content must
be retrieved, the DOM implementation must at least support types appropriate
to the content being processed. Whereas [HTML 4.01], [XML 1.0], and
associated namespace specification [XML Namespaces] rely on [IETF RFC 2396],
other specifications such as namespaces in XML 1.1 [XML Namespaces 1.1] may
rely on alternative resource identifier types, requiring support for
alternative resource identifier types where required by applicable
specifications.
Regardless of the exact type of a DOM URI, the term "absolute URI" refers to
a complete resource identifier and the term "relative URI" refers to an
incomplete resource identifier.
1.3.3 XML Namespaces
DOM Level 2 and 3 support XML namespaces [XML Namespaces] by augmenting
several interfaces of the DOM Level 1 Core to allow creating and
manipulating elements and attributes associated to a namespace. When [XML
1.1] is in use (see Document.xmlVersion), DOM Level 3 also supports [XML
Namespaces 1.1].
As far as the DOM is concerned, special attributes used for declaring XML
namespaces are still exposed and can be manipulated just like any other
attribute. However, nodes are permanently bound to namespace URIs as they
get created. Consequently, moving a node within a document, using the DOM,
in no case results in a change of its namespace prefix or namespace URI.
Similarly, creating a node with a namespace prefix and namespace URI, or
changing the namespace prefix of a node, does not result in any addition,
removal, or modification of any special attributes for declaring the
appropriate XML namespaces. Namespace validation is not enforced; the DOM
application is responsible. In particular, since the mapping between
prefixes and namespace URIs is not enforced, in general, the resulting
document cannot be serialized naively. For example, applications may have to
declare every namespace in use when serializing a document.
In general, the DOM implementation (and higher) doesn't perform any URI
normalization or canonicalization. The URIs given to the DOM are assumed to
be valid (e.g., characters such as white spaces are properly escaped), and
no lexical checking is performed. Absolute URI references are treated as
strings and compared literally. How relative namespace URI references are
treated is undefined. To ensure interoperability only absolute namespace URI
references (i.e., URI references beginning with a scheme name and a colon)
should be used. Applications should use the value null as the namespaceURI
parameter for methods if they wish to have no namespace. In programming
languages where empty strings can be differentiated from null, the way empty
strings are treated, when given as a namespace URI to a DOM Level 2 method,
is implementation dependent. This is true even though the DOM does no
lexical checking of URIs.
Note: Element.setAttributeNS(null, ...) put the attribute in the
per-element-type partitions as defined in XML Namespace Partitions in [XML
Namespaces].
Note: In the DOM, all namespace declaration attributes are by definition
bound to the namespace URI: "http://www.w3.org/2000/xmlns/". These are the
attributes whose namespace prefix or qualified name is "xmlns". Although, at
the time of writing, this is not part of the XML Namespaces specification
[XML Namespaces], it is planned to be incorporated in a future revision.
In a document with no namespaces, the child list of an EntityReference node
is always the same as that of the corresponding Entity. This is not true in
a document where an entity contains unbound namespace prefixes. In such a
case, the descendants of the corresponding EntityReference nodes may be
bound to different namespace URIs, depending on where the entity references
are. Also, because, in the DOM, nodes always remain bound to the same
namespace URI, moving such EntityReference nodes can lead to documents that
cannot be serialized. This is also true when the DOM Level 1 method
Document.createEntityReference(name) is used to create entity references
that correspond to such entities, since the descendants of the returned
EntityReference are unbound. The DOM Level 2 does not support any mechanism
to resolve namespace prefixes. For all of these reasons, use of such
entities and entity references should be avoided or used with extreme care.
A future Level of the DOM may include some additional support for handling
these.
The new methods, such as Document.createElementNS(namespaceURI,
qualifiedName) and Document.createAttributeNS(namespaceURI, qualifiedName),
are meant to be used by namespace aware applications. Simple applications
that do not use namespaces can use the DOM Level 1 methods, such as
Document.createElement(tagName) and Document.createAttribute(name). Elements
and attributes created in this way do not have any namespace prefix,
namespace URI, or local name.
Note: DOM Level 1 methods are namespace ignorant. Therefore, while it is
safe to use these methods when not dealing with namespaces, using them and
the new ones at the same time should be avoided. DOM Level 1 methods solely
identify attribute nodes by their Node.nodeName. On the contrary, the DOM
Level 2 methods related to namespaces, identify attribute nodes by their
Node.namespaceURI and Node.localName. Because of this fundamental
difference, mixing both sets of methods can lead to unpredictable results.
In particular, using Element.setAttributeNS(namespaceURI, qualifiedName,
value), an element may have two attributes (or more) that have the same
Node.nodeName, but different Node.namespaceURIs. Calling
Element.getAttribute(name) with that nodeName could then return any of those
attributes. The result depends on the implementation. Similarly, using
Element.setAttributeNode(newAttr), one can set two attributes (or more) that
have different Node.nodeNames but the same Node.prefix and
Node.namespaceURI. In this case Element.getAttributeNodeNS(namespaceURI,
localName) will return either attribute, in an implementation dependent
manner. The only guarantee in such cases is that all methods that access a
named item by its nodeName will access the same item, and all methods which
access a node by its URI and local name will access the same node. For
instance, Element.setAttribute(name, value) and
Element.setAttributeNS(namespaceURI, qualifiedName, value) affect the node
that Element.getAttribute(name) and Element.getAttributeNS(namespaceURI,
localName), respectively, return.
1.3.4 Base URIs
The DOM Level 3 adds support for the [base URI] property defined in [XML
Information set] by providing a new attribute on the Node interface that
exposes this information. However, unlike the Node.namespaceURI attribute,
the Node.baseURI attribute is not a static piece of information that every
node carries. Instead, it is a value that is dynamically computed according
to [XML Base]. This means its value depends on the location of the node in
the tree and moving the node from one place to another in the tree may
affect its value. Other changes, such as adding or changing an xml:base
attribute on the node being queried or one of its ancestors may also affect
its value.
One consequence of this it that when external entity references are expanded
while building a Document one may need to add, or change, an xml:base
attribute to the Element nodes originally contained in the entity being
expanded so that the Node.baseURI returns the correct value. In the case of
ProcessingInstruction nodes originally contained in the entity being
expanded the information is lost. [DOM Level 3 Load and Save] handles
elements as described here and generates a warning in the latter case.
1.3.5 Mixed DOM implementations
As new XML vocabularies are developed, those defining the vocabularies are
also beginning to define specialized APIs for manipulating XML instances of
those vocabularies. This is usually done by extending the DOM to provide
interfaces and methods that perform operations frequently needed their
users. For example, the MathML [MathML 2.0] and SVG [SVG 1.0] specifications
are developing DOM extensions to allow users to manipulate instances of
these vocabularies using semantics appropriate to images and mathematics
(respectively) as well as the generic DOM XML semantics. Instances of SVG or
MathML are often embedded in XML documents conforming to a different schema
such as XHTML.
While the Namespaces in XML specification [XML Namespaces] provides a
mechanism for integrating these documents at the syntax level, it has become
clear that the DOM Level 2 Recommendation [DOM Level 2 Core] is not rich
enough to cover all the issues that have been encountered in having these
different DOM implementations be used together in a single application. DOM
Level 3 deals with the requirements brought about by embedding fragments
written according to a specific markup language (the embedded component) in
a document where the rest of the markup is not written according to that
specific markup language (the host document). It does not deal with
fragments embedded by reference or linking.
A DOM implementation supporting DOM Level 3 Core should be able to
collaborate with subcomponents implementing specific DOMs to assemble a
compound document that can be traversed and manipulated via DOM interfaces
as if it were a seamless whole.
The normal typecast operation on an object should support the interfaces
expected by legacy code for a given document type. Typecasting techniques
may not be adequate for selecting between multiple DOM specializations of an
object which were combined at run time, because they may not all be part of
the same object as defined by the binding's object model. Conflicts are most
obvious with the Document object, since it is shared as owner by the rest of
the document. In a homogeneous document, elements rely on the Document for
specialized services and construction of specialized nodes. In a
heterogeneous document, elements from different modules expect different
services and APIs from the same Document object, since there can only be one
owner and root of the document hierarchy.
1.3.6 DOM Features
Each DOM module defines one or more features, as listed in the conformance
section (Conformance). Features are case-insensitive and are also defined
for a specific set of versions. For example, this specification defines the
features "Core" and "XML", and thus for the versions "1.0", "2.0", and
"3.0". To avoid possible conflicts, as a convention, names referring to
features defined outside the DOM specification should be made unique.
Applications could then request for features to be supported by a DOM
implementation using the methods
DOMImplementationSource.getDOMImplementation(features) or
DOMImplementationSource.getDOMImplementations(features), check the features
supported by a DOM implementation using the method
DOMImplementation.hasFeature(feature, version), or by a specific node using
Node.isSupported(feature, version). Note that when using the methods that
take a feature and a version as parameters, applications can use null or
empty string for the version parameter if they don't wish to specify a
particular version for the specified feature.
Up to the DOM Level 2 modules, all interfaces, that were an extension of
existing ones, were accessible using binding-specific casting mechanisms if
the feature associated to the extension was supported. For example, an
instance of the EventTarget interface could be obtained from an instance of
the Node interface if the feature "Events" was supported by the node.
As discussed Mixed DOM implementations, DOM Level 3 Core should be able to
collaborate with subcomponents implementing specific DOMs. For that effect,
the methods DOMImplementation.getFeature(feature, version) and
Node.getFeature(feature, version) were introduced. If a plus sign "+" is
prepended to any feature name, implementations are considered in which the
specified feature may not be directly castable but would require discovery
through getFeature. Without a plus, only features whose interfaces are
directly castable are considered.
// example 1, without prepending the "+"
if (myNode.isSupported("Events", "3.0")) {
EventTarget evt = (EventTarget) myNode;
// ...
}
// example 2, with the "+"
if (myNode.isSupported("+Events", "3.0")) {
// (the plus sign "+" is irrelevant for the getFeature method itself
// and is ignored by this method anyway)
EventTarget evt = (EventTarget) myNode.getFeature("Events", "3.0");
// ...
}
1.3.7 Bootstrapping
Because previous versions of the DOM specification only defined a set of
interfaces, applications had to rely on some implementation dependent code
to start from. However, hard-coding the application to a specific
implementation prevents the application from running on other
implementations and from using the most-suitable implementation of the
environment. At the same time, implementations may also need to load modules
or perform other setup to efficiently adapt to different and sometimes
mutually-exclusive feature sets.
To solve these problems this specification introduces a
DOMImplementationRegistry object with a function that lets an application
find implementations, based on the specific features it requires. How this
object is found and what it exactly looks like is not defined here, because
this cannot be done in a language-independent manner. Instead, each language
binding defines its own way of doing this. See Java Language Binding and
ECMAScript Language Binding for specifics.
In all cases, though, the DOMImplementationRegistry provides a
getDOMImplementation method accepting a features string, which is passed to
every known DOMImplementationSource until a suitable DOMImplementation is
found and returned. The DOMImplementationRegistry also provides a
getDOMImplementations method accepting a features string, which is passed to
every known DOMImplementationSource, and returns a list of suitable
DOMImplementations. Those two methods are the same as the ones found on the
DOMImplementationSource interface defined below.
Any number of DOMImplementationSource objects can be registered. A source
may return one or more DOMImplementation singletons or construct new
DOMImplementation objects, depending upon whether the requested features
require specialized state in the DOMImplementation object.
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
exception DOMException {
unsigned short code;
};
// ExceptionCode
const unsigned short INDEX_SIZE_ERR = 1;
const unsigned short DOMSTRING_SIZE_ERR = 2;
const unsigned short HIERARCHY_REQUEST_ERR = 3;
const unsigned short WRONG_DOCUMENT_ERR = 4;
const unsigned short INVALID_CHARACTER_ERR = 5;
const unsigned short NO_DATA_ALLOWED_ERR = 6;
const unsigned short NO_MODIFICATION_ALLOWED_ERR = 7;
const unsigned short NOT_FOUND_ERR = 8;
const unsigned short NOT_SUPPORTED_ERR = 9;
const unsigned short INUSE_ATTRIBUTE_ERR = 10;
// Introduced in DOM Level 2:
const unsigned short INVALID_STATE_ERR = 11;
// Introduced in DOM Level 2:
const unsigned short SYNTAX_ERR = 12;
// Introduced in DOM Level 2:
const unsigned short INVALID_MODIFICATION_ERR = 13;
// Introduced in DOM Level 2:
const unsigned short NAMESPACE_ERR = 14;
// Introduced in DOM Level 2:
const unsigned short INVALID_ACCESS_ERR = 15;
// Introduced in DOM Level 3:
const unsigned short VALIDATION_ERR = 16;
// Introduced in DOM Level 3:
const unsigned short TYPE_MISMATCH_ERR = 17;
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 a 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 parallel pairs of name and namespace 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
// Introduced in DOM Level 3:
interface DOMStringList {
DOMString item(in unsigned long index);
readonly attribute unsigned long length;
};
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
item
Returns the indexth item in the collection. If index is
greater than or equal to the number of DOMStrings in the
list, this returns null.
Parameters
index of type unsigned long
Index into the collection.
Return Value
DOMString The DOMString at the indexth position in the
DOMStringList, or null if that is not a valid
index.
No Exceptions
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, 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
// Introduced in DOM Level 3:
interface NameList {
DOMString getName(in unsigned long index)
raises(DOMException);
DOMString getNamespaceURI(in unsigned long index)
raises(DOMException);
readonly attribute unsigned long length;
};
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
getName
Returns the indexth name item in the collection.
Parameters
index of type unsigned long
Index into the collection.
Return Value
DOMString The DOMString at the indexth position in the
NameList.
Exceptions
DOMException INDEX_SIZE_ERR: If index is greater than or
equal to the number of nodes in the list.
getNamespaceURI
Returns the indexth namespaceURI item in the collection.
Parameters
index of type unsigned long
Index into the collection.
Return Value
DOMString The DOMString at the indexth position in the
NameList.
Exceptions
DOMException INDEX_SIZE_ERR: If index is greater than or
equal to the number of nodes in the list.
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
// Introduced in DOM Level 3:
interface DOMImplementationList {
DOMImplementation item(in unsigned long index);
readonly attribute unsigned long length;
};
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
Returns the indexth item in the collection. If index is
greater than or equal to the number of DOMImplementations in
the list, this returns null.
Parameters
index of type unsigned long
Index into the collection.
Return Value
DOMImplementation The DOMImplementation at the indexth
position in the DOMImplementationList, or
null if that is not a valid index.
No Exceptions
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
// Introduced in DOM Level 3:
interface DOMImplementationSource {
DOMImplementation getDOMImplementation(in DOMString features);
DOMImplementationList getDOMImplementations(in DOMString features);
};
Methods
getDOMImplementation
A method to request the first DOM implementation that support
the specified features.
Parameters
features of type DOMString
A string that specifies which features and versions are
required. This is a space separated list in which each
feature is specified by its name optionally followed by
a space and a version number.
As an example, the string "XML 3.0 Traversal +Events
2.0" will request a DOM implementation that supports the
module "XML" for its 3.0 version, a module that support
of the "Traversal" module for any version, and the
module "Events" for its 2.0 version. The module "Events"
must be accessible using the method Node.getFeature()
and DOMImplementation.getFeature().
Return Value
DOMImplementation The first DOM implementation that support
the desired features, or null if this
source has none.
No Exceptions
getDOMImplementations
A method to request a list of DOM implementations that
support the specified features and versions, as specified in
DOM Features.
Parameters
features of type DOMString
A string that specifies which features and versions are
required. This is a space separated list in which each
feature is specified by its name optionally followed by
a space and a version number. This is something like:
"XML 3.0 Traversal +Events 2.0"
Return Value
DOMImplementationList A list of DOM implementations that
support the desired features.
No Exceptions
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
interface DOMImplementation {
boolean hasFeature(in DOMString feature,
in DOMString version);
// Introduced in DOM Level 2:
DocumentType createDocumentType(in DOMString qualifiedName,
in DOMString publicId,
in DOMString systemId)
raises(DOMException);
// Introduced in DOM Level 2:
Document createDocument(in DOMString namespaceURI,
in DOMString qualifiedName,
in DocumentType doctype)
raises(DOMException);
// Introduced in DOM Level 3:
DOMObject getFeature(in DOMString feature,
in DOMString version);
};
Methods
createDocument introduced in DOM Level 2
Creates a DOM Document object of the specified type with its
document element.
Note that based on the DocumentType given to create the
document, the implementation may instantiate specialized
Document objects that support additional features than the
"Core", such as "HTML" [DOM Level 2 HTML]. On the other hand,
setting the DocumentType after the document was created makes
this very unlikely to happen. Alternatively, specialized
Document creation methods, such as createHTMLDocument [DOM
Level 2 HTML], can be used to obtain specific types of
Document objects.
Parameters
namespaceURI of type DOMString
The namespace URI of the document element to create or
null.
qualifiedName of type DOMString
The qualified name of the document element to be created
or null.
doctype of type DocumentType
The type of document to be created or null.
When doctype is not null, its Node.ownerDocument
attribute is set to the document being created.
Return Value
Document A new Document object with its document element. If
the NamespaceURI, qualifiedName, and doctype are
null, the returned Document is empty with no
document element.
Exceptions
DOMException INVALID_CHARACTER_ERR: Raised if the specified
qualified name contains an illegal character
according to [XML 1.0].
NAMESPACE_ERR: Raised if the qualifiedName is
malformed, if the qualifiedName has a prefix
and the namespaceURI is null, or if the
qualifiedName is null and the namespaceURI is
different from null, or if the qualifiedName
has a prefix that is "xml" and the namespaceURI
is different from
"http://www.w3.org/XML/1998/namespace" [XML
Namespaces], or if the DOM implementation does
not support the "XML" feature but a non-null
namespace URI was provided, since namespaces
were defined by XML.
WRONG_DOCUMENT_ERR: Raised if doctype has
already been used with a different document or
was created from a different implementation.
NOT_SUPPORTED_ERR: May be raised if the
implementation does not support the feature
"XML" and the language exposed through the
Document does not support XML Namespaces (such
as [HTML 4.01]).
createDocumentType introduced in DOM Level 2
Creates an empty DocumentType node. Entity declarations and
notations are not made available. Entity reference expansions
and default attribute additions do not occur..
Parameters
qualifiedName of type DOMString
The qualified name of the document type to be created.
publicId of type DOMString
The external subset public identifier.
systemId of type DOMString
The external subset system identifier.
Return Value
DocumentType A new DocumentType node with Node.ownerDocument
set to null.
Exceptions
DOMException INVALID_CHARACTER_ERR: Raised if the specified
qualified name contains an illegal character
according to [XML 1.0].
NAMESPACE_ERR: Raised if the qualifiedName is
malformed.
NOT_SUPPORTED_ERR: May be raised if the
implementation does not support the feature
"XML" and the language exposed through the
Document does not support XML Namespaces (such
as [HTML 4.01]).
getFeature introduced in DOM Level 3
This method returns a specialized object which implements the
specialized APIs of the specified feature and version, as
specified in DOM Features. The specialized object may also be
obtained by using binding-specific casting methods but is not
necessarily expected to, as discussed in Mixed DOM
implementations. This method also allow the implementation to
provide specialized objects which do not support the
DOMImplementation interface.
Parameters
feature of type DOMString
The name of the feature requested. Note that any plus
sign "+" prepended to the name of the feature will be
ignored since it is not significant in the context of
this method.
version of type DOMString
This is the version number of the feature to test.
Return Value
DOMObject Returns an object which implements the specialized
APIs of the specified feature and version, if any,
or null if there is no object which implements
interfaces associated with that feature. If the
DOMObject returned by this method implements the
DOMImplementation interface, it must delegate to
the primary core DOMImplementation and not return
results inconsistent with the primary core
DOMImplementation such as hasFeature, getFeature,
etc.
No Exceptions
hasFeature
Test if the DOM implementation implements a specific feature
and version, as specified in DOM Features.
Parameters
feature of type DOMString
The name of the feature to test.
version of type DOMString
This is the version number of the feature to test.
Return Value
boolean true if the feature is implemented in the specified
version, false otherwise.
No Exceptions
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 insertBefore and appendChild.
IDL Definition
interface DocumentFragment : Node {
};
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
interface Document : Node {
// Modified in DOM Level 3:
readonly attribute DocumentType doctype;
readonly attribute DOMImplementation implementation;
readonly attribute Element documentElement;
Element createElement(in DOMString tagName)
raises(DOMException);
DocumentFragment createDocumentFragment();
Text createTextNode(in DOMString data);
Comment createComment(in DOMString data);
CDATASection createCDATASection(in DOMString data)
raises(DOMException);
ProcessingInstruction createProcessingInstruction(in DOMString target,
in DOMString data)
raises(DOMException);
Attr createAttribute(in DOMString name)
raises(DOMException);
EntityReference createEntityReference(in DOMString name)
raises(DOMException);
NodeList getElementsByTagName(in DOMString tagname);
// Introduced in DOM Level 2:
Node importNode(in Node importedNode,
in boolean deep)
raises(DOMException);
// Introduced in DOM Level 2:
Element createElementNS(in DOMString namespaceURI,
in DOMString qualifiedName)
raises(DOMException);
// Introduced in DOM Level 2:
Attr createAttributeNS(in DOMString namespaceURI,
in DOMString qualifiedName)
raises(DOMException);
// Introduced in DOM Level 2:
NodeList getElementsByTagNameNS(in DOMString namespaceURI,
in DOMString localName);
// Introduced in DOM Level 2:
Element getElementById(in DOMString elementId);
// Introduced in DOM Level 3:
readonly attribute DOMString actualEncoding;
// Introduced in DOM Level 3:
attribute DOMString xmlEncoding;
// Introduced in DOM Level 3:
attribute boolean xmlStandalone;
// raises(DOMException) on setting
// Introduced in DOM Level 3:
attribute DOMString xmlVersion;
// raises(DOMException) on setting
// Introduced in DOM Level 3:
attribute boolean strictErrorChecking;
// Introduced in DOM Level 3:
attribute DOMString documentURI;
// Introduced in DOM Level 3:
Node adoptNode(in Node source)
raises(DOMException);
// Introduced in DOM Level 3:
readonly attribute DOMConfiguration config;
// Introduced in DOM Level 3:
void normalizeDocument();
// Introduced in DOM Level 3:
Node renameNode(in Node n,
in DOMString namespaceURI,
in DOMString qualifiedName)
raises(DOMException);
};
Attributes
actualEncoding of type DOMString, readonly, introduced in DOM
Level 3
An attribute specifying the actual encoding of this document.
This is null when it is not known.
config of type DOMConfiguration, readonly, introduced in DOM Level
3
The configuration used when Document.normalizeDocument() is
invoked.
doctype of type DocumentType, readonly, modified in DOM Level 3
The Document Type Declaration (see DocumentType) associated
with this document. For HTML documents as well as XML
documents without a document type declaration this returns
null.
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 insertBefore, or
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.
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.
implementation of type DOMImplementation, readonly
The DOMImplementation object that handles this document. A
DOM application may use objects from multiple
implementations.
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, introduced in DOM Level 3
An attribute specifying, as part of the XML declaration, the
encoding of this document. This is null when unspecified.
xmlStandalone of type boolean, introduced in DOM Level 3
An attribute specifying, as part of the XML declaration,
whether this document is standalone.
Exceptions on setting
DOMException NOT_SUPPORTED_ERR: Raised if this document does
support the "XML" feature.
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,
the value is "1.0". Changing this attribute will affect
methods that check for illegal characters in XML names.
Application should invoke Document.normalizeDocument() in
order to check for illegal characters in the Nodes that are
already part of this Document.
Exceptions on setting
DOMException NOT_SUPPORTED_ERR: Raised if the version is set
to a value that is not supported by this
Document or if this document does support the
"XML" feature.
Methods
adoptNode introduced in DOM Level 3
Changes the ownerDocument of a node, its children, as well as
the attached attribute nodes if there are any. If the node
has a parent it is first removed from its parent child list.
This effectively allows moving a subtree from one document to
another. The following list describes the specifics for each
type of node.
ATTRIBUTE_NODE
The ownerElement attribute is set to null and the
specified flag is set to true on the adopted Attr. The
descendants of the source Attr are recursively adopted.
DOCUMENT_FRAGMENT_NODE
The descendants of the source node are recursively
adopted.
DOCUMENT_NODE
Document nodes cannot be adopted.
DOCUMENT_TYPE_NODE
DocumentType nodes cannot be adopted.
ELEMENT_NODE
Specified attribute nodes of the source element are
adopted, and the generated Attr nodes. Default
attributes are discarded, though if the document being
adopted into defines default attributes for this element
name, those are assigned. The descendants of the source
element are recursively adopted.
ENTITY_NODE
Entity nodes cannot be adopted.
ENTITY_REFERENCE_NODE
Only the EntityReference node itself is adopted, the
descendants are discarded, since the source and
destination documents might have defined the entity
differently. If the document being imported into
provides a definition for this entity name, its value is
assigned.
NOTATION_NODE
Notation nodes cannot be adopted.
PROCESSING_INSTRUCTION_NODE, TEXT_NODE, CDATA_SECTION_NODE,
COMMENT_NODE
These nodes can all be adopted. No specifics.
Note: Unlike the Document.importNode() method, this method
does not raise an INVALID_CHARACTER_ERR exception and
applications should use the Document.normalizeDocument()
method to check if an imported name contain an illegal
character according to the XML version in use.
Parameters
source of type Node
The node to move into this document.
Return Value
Node The adopted node, or null if this operation fails, such
as when the source node comes from a different
implementation.
Exceptions
DOMException NOT_SUPPORTED_ERR: Raised if the source node is
of type DOCUMENT, DOCUMENT_TYPE.
NO_MODIFICATION_ALLOWED_ERR: Raised when the
source node is readonly.
createAttribute
Creates an Attr of the given name. Note that the Attr
instance can then be set on an Element using the
setAttributeNode method.
To create an attribute with a qualified name and namespace
URI, use the createAttributeNS method.
Parameters
name of type DOMString
The name of the attribute.
Return Value
Attr A new Attr object with the nodeName attribute set to
name, and localName, prefix, and namespaceURI set to
null. The value of the attribute is the empty string.
Exceptions
DOMException INVALID_CHARACTER_ERR: Raised if the specified
name contains an illegal character according to
the XML version in use specified in the version
attribute.
createAttributeNS introduced in DOM Level 2
Creates an attribute of the given qualified name and
namespace URI.
Per [XML Namespaces], applications must use the value null as
the namespaceURI parameter for methods if they wish to have
no namespace.
Parameters
namespaceURI of type DOMString
The namespace URI of the attribute to create.
qualifiedName of type DOMString
The qualified name of the attribute to instantiate.
Return Value
Attr A new Attr object with the following attributes:
Attribute Value
Node.nodeName qualifiedName
Node.namespaceURInamespaceURI
Node.prefix prefix, extracted from
qualifiedName, or null if there is
no prefix
Node.localName local name, extracted from
qualifiedName
Attr.name qualifiedName
Node.nodeValue the empty string
Exceptions
DOMException INVALID_CHARACTER_ERR: Raised if the specified
qualifiedName contains an illegal character
according to the XML version in use specified
in the version attribute.
NAMESPACE_ERR: Raised if the qualifiedName is a
malformed qualified name, if the qualifiedName
has a prefix and the namespaceURI is null, if
the qualifiedName has a prefix that is "xml"
and the namespaceURI is different from
"http://www.w3.org/XML/1998/namespace", if the
qualifiedName or its prefix is "xmlns" and the
namespaceURI is different from
"http://www.w3.org/2000/xmlns/", or if the
namespaceURI is "http://www.w3.org/2000/xmlns/"
and neither the qualifiedName nor its prefix is
"xmlns".
NOT_SUPPORTED_ERR: Always thrown if the current
document does not support the "XML" feature,
since namespaces were defined by XML.
createCDATASection
Creates a CDATASection node whose value is the specified
string.
Parameters
data of type DOMString
The data for the CDATASection contents.
Return Value
CDATASection The new CDATASection object.
Exceptions
DOMException NOT_SUPPORTED_ERR: Raised if this document is
an HTML document.
createComment
Creates a Comment node given the specified string.
Parameters
data of type DOMString
The data for the node.
Return Value
Comment The new Comment object.
No Exceptions
createDocumentFragment
Creates an empty DocumentFragment object.
Return Value
DocumentFragment A new DocumentFragment.
No Parameters
No Exceptions
createElement
Creates an element of the type specified. Note that the
instance returned implements the Element interface, so
attributes can be specified directly on the returned object.
In addition, if there are known attributes with default
values, Attr nodes representing them are automatically
created and attached to the element.
To create an element with a qualified name and namespace URI,
use the createElementNS method.
Parameters
tagName of type DOMString
The name of the element type to instantiate. For XML,
this is case-sensitive, otherwise it depends on the
case-sensitivity of the markup language in use. In that
case, the name is mapped to the canonical form of that
markup by the DOM implementation.
Return Value
Element A new Element object with the nodeName attribute set
to tagName, and localName, prefix, and namespaceURI
set to null.
Exceptions
DOMException INVALID_CHARACTER_ERR: Raised if the specified
name contains an illegal character according to
the XML version in use specified in the version
attribute.
createElementNS introduced in DOM Level 2
Creates an element of the given qualified name and namespace
URI.
Per [XML Namespaces], applications must use the value null as
the namespaceURI parameter for methods if they wish to have
no namespace.
Parameters
namespaceURI of type DOMString
The namespace URI of the element to create.
qualifiedName of type DOMString
The qualified name of the element type to instantiate.
Return Value
Element A new Element object with the following attributes:
Attribute Value
Node.nodeName qualifiedName
Node.namespaceURInamespaceURI
Node.prefix prefix, extracted from
qualifiedName, or null if there
is no prefix
Node.localName local name, extracted from
qualifiedName
Element.tagName qualifiedName
Exceptions
DOMException INVALID_CHARACTER_ERR: Raised if the specified
qualifiedName contains an illegal character
according to the XML version in use specified
in the version attribute.
NAMESPACE_ERR: Raised if the qualifiedName is a
malformed qualified name, if the qualifiedName
has a prefix and the namespaceURI is null, or
if the qualifiedName has a prefix that is "xml"
and the namespaceURI is different from
"http://www.w3.org/XML/1998/namespace" [XML
Namespaces], or if the qualifiedName or its
prefix is "xmlns" and the namespaceURI is
different from "http://www.w3.org/2000/xmlns/",
or if the namespaceURI is
"http://www.w3.org/2000/xmlns/" and neither the
qualifiedName nor its prefix is "xmlns".
NOT_SUPPORTED_ERR: Always thrown if the current
document does not support the "XML" feature,
since namespaces were defined by XML.
createEntityReference
Creates an EntityReference object. In addition, if the
referenced entity is known, the child list of the
EntityReference node is made the same as that of the
corresponding Entity node.
Note: If any descendant of the Entity node has an unbound
namespace prefix, the corresponding descendant of the created
EntityReference node is also unbound; (its namespaceURI is
null). The DOM Level 2 and 3 do not support any mechanism to
resolve namespace prefixes in this case.
Parameters
name of type DOMString
The name of the entity to reference.
Return Value
EntityReference The new EntityReference object.
Exceptions
DOMException INVALID_CHARACTER_ERR: Raised if the specified
name contains an illegal character according to
the XML version in use specified in the version
attribute.
NOT_SUPPORTED_ERR: Raised if this document is
an HTML document.
createProcessingInstruction
Creates a ProcessingInstruction node given the specified name
and data strings.
Parameters
target of type DOMString
The target part of the processing instruction.
data of type DOMString
The data for the node.
Return Value
ProcessingInstruction The new ProcessingInstruction object.
Exceptions
DOMException INVALID_CHARACTER_ERR: Raised if the specified
target contains an illegal character according
to the XML version in use specified in the
version attribute.
NOT_SUPPORTED_ERR: Raised if this document is
an HTML document.
createTextNode
Creates a Text node given the specified string.
Parameters
data of type DOMString
The data for the node.
Return Value
Text The new Text object.
No Exceptions
getElementById introduced in DOM Level 2
Returns the Element that has an ID attribute with the given
value. If no such element exists, this returns null. If more
than one element has an ID attribute with that value, what is
returned is undefined.
The DOM implementation is expected to use the method
Attr.isId() to determine if an attribute is of type ID.
Note: Attributes with the name "ID" or "id" are not of type
ID unless so defined.
Parameters
elementId of type DOMString
The unique id value for an element.
Return Value
Element The matching element or null if there is none.
No Exceptions
getElementsByTagName
Returns a NodeList of all the Elements in document order with
a given tag name and are contained in the document.
Parameters
tagname of type DOMString
The name of the tag to match on. The special value "*"
matches all tags. For XML, this is case-sensitive,
otherwise it depends on the case-sensitivity of the
markup language in use.
Return Value
NodeList A new NodeList object containing all the matched
Elements.
No Exceptions
getElementsByTagNameNS introduced in DOM Level 2
Returns a NodeList of all the Elements with a given local
name and namespace URI in document order.
Parameters
namespaceURI of type DOMString
The namespace URI of the elements to match on. The
special value "*" matches all namespaces.
localName of type DOMString
The local name of the elements to match on. The special
value "*" matches all local names.
Return Value
NodeList A new NodeList object containing all the matched
Elements.
No Exceptions
importNode introduced in DOM Level 2
Imports a node from another document to this document. The
returned node has no parent; (parentNode is null). The source
node is not altered or removed from the original document;
this method creates a new copy of the source node.
For all nodes, importing a node creates a node object owned
by the importing document, with attribute values identical to
the source node's nodeName and nodeType, plus the attributes
related to namespaces (prefix, localName, and namespaceURI).
As in the cloneNode operation, the source node is not
altered. User data associated to the imported node is not
carried over. However, if any UserDataHandlers has been
specified along with the associated data these handlers will
be called with the appropriate parameters before this method
returns.
Additional information is copied as appropriate to the
nodeType, attempting to mirror the behavior expected if a
fragment of XML or HTML source was copied from one document
to another, recognizing that the two documents may have
different DTDs in the XML case. The following list describes
the specifics for each type of node.
ATTRIBUTE_NODE
The ownerElement attribute is set to null and the
specified flag is set to true on the generated Attr. The
descendants of the source Attr are recursively imported
and the resulting nodes reassembled to form the
corresponding subtree.
Note that the deep parameter has no effect on Attr
nodes; they always carry their children with them when
imported.
DOCUMENT_FRAGMENT_NODE
If the deep option was set to true, the descendants of
the source DocumentFragment are recursively imported and
the resulting nodes reassembled under the imported
DocumentFragment to form the corresponding subtree.
Otherwise, this simply generates an empty
DocumentFragment.
DOCUMENT_NODE
Document nodes cannot be imported.
DOCUMENT_TYPE_NODE
DocumentType nodes cannot be imported.
ELEMENT_NODE
Specified attribute nodes of the source element are
imported, and the generated Attr nodes are attached to
the generated Element. Default attributes are not
copied, though if the document being imported into
defines default attributes for this element name, those
are assigned. If the importNode deep parameter was set
to true, the descendants of the source element are
recursively imported and the resulting nodes reassembled
to form the corresponding subtree.
ENTITY_NODE
Entity nodes can be imported, however in the current
release of the DOM the DocumentType is readonly. Ability
to add these imported nodes to a DocumentType will be
considered for addition to a future release of the DOM.
On import, the publicId, systemId, and notationName
attributes are copied. If a deep import is requested,
the descendants of the the source Entity are recursively
imported and the resulting nodes reassembled to form the
corresponding subtree.
ENTITY_REFERENCE_NODE
Only the EntityReference itself is copied, even if a
deep import is requested, since the source and
destination documents might have defined the entity
differently. If the document being imported into
provides a definition for this entity name, its value is
assigned.
NOTATION_NODE
Notation nodes can be imported, however in the current
release of the DOM the DocumentType is readonly. Ability
to add these imported nodes to a DocumentType will be
considered for addition to a future release of the DOM.
On import, the publicId and systemId attributes are
copied.
Note that the deep parameter has no effect on this type
of nodes since they cannot have any children.
PROCESSING_INSTRUCTION_NODE
The imported node copies its target and data values from
those of the source node.
Note that the deep parameter has no effect on this type
of nodes since they cannot have any children.
TEXT_NODE, CDATA_SECTION_NODE, COMMENT_NODE
These three types of nodes inheriting from CharacterData
copy their data and length attributes from those of the
source node.
Note that the deep parameter has no effect on these
types of nodes since they cannot have any children.
Parameters
importedNode of type Node
The node to import.
deep of type boolean
If true, recursively import the subtree under the
specified node; if false, import only the node itself,
as explained above. This has no effect on nodes that
cannot have any children, and on Attr, and
EntityReference nodes.
Return Value
Node The imported node that belongs to this Document.
Exceptions
DOMException NOT_SUPPORTED_ERR: Raised if the type of node
being imported is not supported.
INVALID_CHARACTER_ERR: Raised if one the
imported names contain an illegal character
according to the XML version in use specified
in the version attribute. This may happen when
importing an XML 1.1 [XML 1.1] element into an
XML 1.0 document, for instance.
normalizeDocument introduced in DOM Level 3
This method acts as if the document was going through a save
and load cycle, putting the document in a "normal" form. As a
consequence, this method updates the replacement tree of
EntityReference nodes and normalizes Text nodes, as defined
in the method Node.normalize().
Otherwise, the actual result depends on the features being
set on the Document.config object and governing what
operations actually take place. Noticeably this method could
also make the document "namespace wellformed" according to
the algorithm described in Namespace normalization, check the
character normalization, remove the CDATASection nodes, etc.
See DOMConfiguration for details.
// Keep in the document the information defined
// in the XML Information Set (Java example)
DOMConfiguration docConfig = myDocument.getConfig();
docConfig.setParameter("infoset", Boolean.TRUE);
myDocument.normalizeDocument();
Mutation events, when supported, are generated to reflect the
changes occurring on the document.
If errors occur during the invocation of this method, such as
an attempt to update a read-only node or a Node.nodeName
contains an invalid character according to the XML version in
use, errors will be reported using the DOMErrorHandler object
associated with the "error-handler" parameter. Note that this
method does not generate fatal errors.
No Parameters
No Return Value
No Exceptions
renameNode introduced in DOM Level 3
Rename an existing node of type ELEMENT_NODE or
ATTRIBUTE_NODE.
When possible this simply changes the name of the given node,
otherwise this creates a new node with the specified name and
replaces the existing node with the new node as described
below.
If simply changing the name of the given node is not
possible, the following operations are performed: a new node
is created, any registered event listener is registered on
the new node, any user data attached to the old node is
removed from that node, the old node is removed from its
parent if it has one, the children are moved to the new node,
if the renamed node is an Element its attributes are moved to
the new node, the new node is inserted at the position the
old node used to have in its parent's child nodes list if it
has one, the user data that was attached to the old node is
attached to the new node.
When the node being renamed is an Element only the specified
attributes are moved, default attributes originated from the
DTD are updated according to the new element name. In
addition, the implementation may update default attributes
from other schemas. Applications should use
Document.normalizeDocument() to guarantee these attributes
are up-to-date.
When the node being renamed is an Attr that is attached to an
Element, the node is first removed from the Element
attributes map. Then, once renamed, either by modifying the
existing node or creating a new one as described above, it is
put back.
In addition,
+ a user data event NODE_RENAMED is fired,
+ when the implementation supports the feature
"MutationNameEvents", each mutation operation involved
in this method fires the appropriate event, and in the
end the event {http://www.w3.org/2001/xml-events,
DOMElementNameChanged} or
{http://www.w3.org/2001/xml-events,
DOMAttributeNameChanged} is fired.
Parameters
n of type Node
The node to rename.
namespaceURI of type DOMString
The new namespace URI.
qualifiedName of type DOMString
The new qualified name.
Return Value
Node The renamed node. This is either the specified node or
the new node that was created to replace the specified
node.
Exceptions
DOMException NOT_SUPPORTED_ERR: Raised when the type of the
specified node is neither ELEMENT_NODE nor
ATTRIBUTE_NODE, or if the implementation does
not support the renaming of the document
element.
WRONG_DOCUMENT_ERR: Raised when the specified
node was created from a different document than
this document.
NAMESPACE_ERR: Raised if the qualifiedName is a
malformed qualified name, if the qualifiedName
has a prefix and the namespaceURI is null, or
if the qualifiedName has a prefix that is "xml"
and the namespaceURI is different from
"http://www.w3.org/XML/1998/namespace" [XML
Namespaces]. Also raised, when the node being
renamed is an attribute, if the qualifiedName,
or its prefix, is "xmlns" and the namespaceURI
is different from
"http://www.w3.org/2000/xmlns/".
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
interface Node {
// NodeType
const unsigned short ELEMENT_NODE = 1;
const unsigned short ATTRIBUTE_NODE = 2;
const unsigned short TEXT_NODE = 3;
const unsigned short CDATA_SECTION_NODE = 4;
const unsigned short ENTITY_REFERENCE_NODE = 5;
const unsigned short ENTITY_NODE = 6;
const unsigned short PROCESSING_INSTRUCTION_NODE = 7;
const unsigned short COMMENT_NODE = 8;
const unsigned short DOCUMENT_NODE = 9;
const unsigned short DOCUMENT_TYPE_NODE = 10;
const unsigned short DOCUMENT_FRAGMENT_NODE = 11;
const unsigned short NOTATION_NODE = 12;
readonly attribute DOMString nodeName;
attribute DOMString nodeValue;
// raises(DOMException) on setting
// raises(DOMException) on retrieval
readonly attribute unsigned short nodeType;
readonly attribute Node parentNode;
readonly attribute NodeList childNodes;
readonly attribute Node firstChild;
readonly attribute Node lastChild;
readonly attribute Node previousSibling;
readonly attribute Node nextSibling;
readonly attribute NamedNodeMap attributes;
// Modified in DOM Level 2:
readonly attribute Document ownerDocument;
// Modified in DOM Level 3:
Node insertBefore(in Node newChild,
in Node refChild)
raises(DOMException);
// Modified in DOM Level 3:
Node replaceChild(in Node newChild,
in Node oldChild)
raises(DOMException);
// Modified in DOM Level 3:
Node removeChild(in Node oldChild)
raises(DOMException);
Node appendChild(in Node newChild)
raises(DOMException);
boolean hasChildNodes();
Node cloneNode(in boolean deep);
// Modified in DOM Level 2:
void normalize();
// Introduced in DOM Level 2:
boolean isSupported(in DOMString feature,
in DOMString version);
// Introduced in DOM Level 2:
readonly attribute DOMString namespaceURI;
// Introduced in DOM Level 2:
attribute DOMString prefix;
// raises(DOMException) on setting
// Introduced in DOM Level 2:
readonly attribute DOMString localName;
// Introduced in DOM Level 2:
boolean hasAttributes();
// Introduced in DOM Level 3:
readonly attribute DOMString baseURI;
// DocumentPosition
const unsigned short DOCUMENT_POSITION_DISCONNECTED = 0x01;
const unsigned short DOCUMENT_POSITION_PRECEDING = 0x02;
const unsigned short DOCUMENT_POSITION_FOLLOWING = 0x04;
const unsigned short DOCUMENT_POSITION_CONTAINS = 0x08;
const unsigned short DOCUMENT_POSITION_CONTAINED_BY = 0x10;
const unsigned short DOCUMENT_POSITION_IMPLEMENTATION_SPECIFIC = 0x20;
// Introduced in DOM Level 3:
unsigned short compareDocumentPosition(in Node other)
raises(DOMException);
// Introduced in DOM Level 3:
attribute DOMString textContent;
// raises(DOMException) on setting
// raises(DOMException) on retrieval
// Introduced in DOM Level 3:
boolean isSameNode(in Node other);
// Introduced in DOM Level 3:
DOMString lookupPrefix(in DOMString namespaceURI);
// Introduced in DOM Level 3:
boolean isDefaultNamespace(in DOMString namespaceURI);
// Introduced in DOM Level 3:
DOMString lookupNamespaceURI(in DOMString prefix);
// Introduced in DOM Level 3:
boolean isEqualNode(in Node arg);
// Introduced in DOM Level 3:
DOMObject getFeature(in DOMString feature,
in DOMString version);
// Introduced in DOM Level 3:
DOMUserData setUserData(in DOMString key,
in DOMUserData data,
in UserDataHandler handler);
// Introduced in DOM Level 3:
DOMUserData getUserData(in DOMString key);
};
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, null