Appendix C: Infoset Mapping

Editor:: Philippe Le Hégaret, W3C

C.1 Document Node Mapping
- C.1.1 Infoset to Document Node
- C.1.2 Document Node to Infoset
C.2 Element Node Mapping
- C.2.1 Infoset to Element Node
- C.2.2 Element Node to Infoset
C.3 Attr Node Mapping
- C.3.1 Infoset to Attr Node
- C.3.2 Attr Node to Infoset
C.4 ProcessingInstruction Node Mapping
- C.4.1 Infoset to ProcessingInstruction Node
- C.4.2 ProcessingInstruction Node to Infoset
C.5 EntityReference Node Mapping
- C.5.1 Infoset to EntityReference Node
- C.5.2 EntityReference Node to Infoset
C.6 Text and CDATASection Nodes Mapping
- C.6.1 Infoset to Text Node
- C.6.2 Text and CDATASection Nodes to Infoset
C.7 Comment Node Mapping
- C.7.1 Infoset to Comment Node
- C.7.2 Comment Node to Infoset
C.8 DocumentType Node Mapping
- C.8.1 Infoset to DocumentType Node
- C.8.2 DocumentType Node to Infoset
C.9 Entity Node Mapping
- C.9.1 Infoset to Entity Node
- C.9.2 Entity Node to Infoset
C.10 Notation Node Mapping
- C.10.1 Infoset to Notation Node
- C.10.2 Notation Node to Infoset

This appendix contains the mappings between the XML Information Set [XML Information Set] model and the Document Object Model. Starting from a Document node, each information item is mapped to its respective Node, and each Node is mapped to its respective information item. As used in the Infoset specification, the Infoset property names are shown in square brackets, [thus].

Unless specified, the Infoset to DOM node mapping makes no distinction between unknown and no value since both will be exposed as null (or false if the DOM attribute is of type boolean).

C.1 Document Node Mapping

C.1.1 Infoset to Document Node

An document information item maps to a Document node. The attributes of the corresponding Document node are constructed as follows:

Attribute	Value
`Node.nodeName`	`"#document"`
`Node.nodeValue`	`null`
`Node.nodeType`	`Node.DOCUMENT_NODE`
`Node.parentNode`	`null`
`Node.childNodes`	A `NodeList` containing the information items in the [children] property.
`Node.firstChild`	The first node contained in `Node.childNodes`
`Node.lastChild`	The last node contained in `Node.childNodes`
`Node.previousSibling`	`null`
`Node.nextSibling`	`null`
`Node.attributes`	`null`
`Node.ownerDocument`	`null`
`Node.namespaceURI`	`null`
`Node.prefix`	`null`
`Node.localName`	`null`
`Node.baseURI`	same as `Document.documentURI`
`Node.textContent`	`null`
`Document.doctype`	The document type information item
`Document.implementation`	The `DOMImplementation` object used to create this node
`Document.documentElement`	The [document element] property
`Document.inputEncoding`	The [character encoding scheme] property
`Document.xmlEncoding`	`null`
`Document.xmlStandalone`	The [standalone] property, or `false` if the latter has no value.
`Document.xmlVersion`	The [version] property, or `"1.0"` if the latter has no value.
`Document.strictErrorChecking`	`true`
`Document.documentURI`	The [base URI] property
`Document.domConfig`	A `DOMConfiguration` object whose parameters are set to their default values

The [notations], [unparsed entities] properties are being exposed in the DocumentType node.

Note: The [all declarations processed] property is not exposed through the Document node.

C.1.2 Document Node to Infoset

A Document node maps to an document information item. Document nodes with no namespace URI (Node.namespaceURI equals to null) cannot be represented using the Infoset. The properties of the corresponding document information item are constructed as follows:

Property	Value
[children]	`Node.childNodes`
[document element]	`Document.documentElement`
[notations]	`Document.doctype.notations`
[unparsed entities]	The information items from `Document.doctype.entities`, whose `Node.childNodes` is an empty list
[base URI]	`Document.documentURI`
[character encoding scheme]	`Document.inputEncoding`
[standalone]	`Document.xmlStandalone`
[version]	`Document.xmlVersion`
[all declarations processed]	The value is implementation dependent

C.2 Element Node Mapping

C.2.1 Infoset to Element Node

An element information item maps to a Element node. The attributes of the corresponding Element node are constructed as follows:

Attribute	Value
`Node.nodeName`	same as `Element.tagName`
`Node.nodeValue`	`null`
`Node.nodeType`	`Node.ELEMENT_NODE`
`Node.parentNode`	The [parent] property
`Node.childNodes`	A `NodeList` containing the information items in the [children] property
`Node.firstChild`	The first node contained in `Node.childNodes`
`Node.lastChild`	The last node contained in `Node.childNodes`
`Node.previousSibling`	The information item preceding the current one on the [children] property contained in the [parent] property
`Node.nextSibling`	The information item following the current one on the [children] property contained in the [parent] property
`Node.attributes`	The information items contained in the [attributes] and [namespace attributes] properties
`Node.ownerDocument`	The document information item
`Node.namespaceURI`	The [namespace name] property
`Node.prefix`	The [prefix] property
`Node.localName`	The [local name] property
`Node.baseURI`	The [base URI] property
`Node.textContent`	Concatenation of the `Node.textContent` attribute value of every child node, excluding `COMMENT_NODE` and `PROCESSING_INSTRUCTION_NODE` nodes. This is the empty string if the node has no children.
`Element.tagName`	If the [prefix] property has no value, this contains the [local name] property. Otherwise, this contains the concatenation of the [prefix] property, the colon ':' character, and the [local name] property.
`Element.schemaTypeInfo`	A `TypeInfo` object whose `TypeInfo.typeNamespace` and `TypeInfo.typeName` are inferred from the schema in use if available.

Note: The [in-scope namespaces] property is not exposed through the Element node.

C.2.2 Element Node to Infoset

An Element node maps to an element information item. Because the Infoset only represents unexpanded entity references, non-empty EntityReference nodes contained in Node.childNodes need to be replaced by their content. DOM applications could use the Document.normalizeDocument() method for that effect with the "entities" parameter set to false. The properties of the corresponding element information item are constructed as follows:

Property	Value
[namespace name]	`Node.namespaceURI`
[local name]	`Node.localName`
[prefix]	`Node.prefix`
[children]	`Node.childNodes`, whose expanded entity references (`EntityReference` nodes with children) have been replaced with their content.
[attributes]	The nodes contained in `Node.attributes`, whose `Node.namespaceURI` value is different from `"http://www.w3.org/2000/xmlns/"`
[namespace attributes]	The nodes contained in `Node.attributes`, whose `Node.namespaceURI` value is `"http://www.w3.org/2000/xmlns/"`
[in-scope namespaces]	The namespace information items computed using the [namespace attributes] properties of this node and its ancestors. If the [DOM Level 3 XPath] module is supported, the namespace information items can also be computed from the `XPathNamespace` nodes.
[base URI]	`Node.baseURI`
[parent]	`Node.parentNode`

C.3 Attr Node Mapping

C.3.1 Infoset to Attr Node

An attribute information item map to a Attr node. The attributes of the corresponding Attr node are constructed as follows:

Attribute/Method	Value
`Node.nodeName`	same as `Attr.name`
`Node.nodeValue`	same as `Attr.value`
`Node.nodeType`	`Node.ATTRIBUTE_NODE`
`Node.parentNode`	`null`
`Node.childNodes`	A `NodeList` containing one `Text` node whose text content is the same as `Attr.value`.
`Node.firstChild`	The `Text` node contained in `Node.childNodes`
`Node.lastChild`	The `Text` node contained in `Node.childNodes`
`Node.previousSibling`	`null`
`Node.nextSibling`	`null`
`Node.attributes`	`null`
`Node.ownerDocument`	The document information item
`Node.namespaceURI`	The [namespace name] property
`Node.prefix`	The [prefix] property
`Node.localName`	The [local name] property
`Node.baseURI`	`null`
`Node.textContent`	the value of `Node.textContent` of the `Text` child. same as `Node.nodeValue` (since this attribute node only contains one `Text` node)
`Attr.name`	If the [prefix] property has no value, this contains the [local name] property. Otherwise, this contains the concatenation of the [prefix] property, the colon ':' character, and the [local name] property.
`Attr.specified`	The [specified] property
`Attr.value`	The [normalized value] property
`Attr.ownerElement`	The [owner element] property
`Attr.schemaTypeInfo`	A `TypeInfo` object whose `TypeInfo.typeNamespace` is `"http://www.w3.org/TR/REC-xml"` and `TypeInfo.typeName` is the [attribute type] property
`Attr.isId`	if the [attribute type] property is ID, this method return `true`

C.3.2 Attr Node to Infoset

An Attr node maps to an attribute information item. Attr nodes with no namespace URI (Node.namespaceURI equals to null) cannot be represented using the Infoset. The properties of the corresponding attribute information item are constructed as follows:

Property	Value
[namespace name]	`Node.namespaceURI`
[local name]	`Node.localName`
[prefix]	`Node.prefix`
[normalized value]	`Attr.value`
[specified]	`Attr.specified`
[attribute type]	Using the `TypeInfo` object referenced from `Attr.schemaTypeInfo`, the value of `TypeInfo.typeName` if `TypeInfo.typeNamespace` is `"http://www.w3.org/TR/REC-xml"`.
[references]	if the computed [attribute type] property is IDREF, IDREFS, ENTITY, ENTITIES, or NOTATION, the value of this property is an ordered list of the element, unparsed entity, or notation information items referred to in the attribute value, in the order that they appear there. The ordered list is computed using `Node.ownerDocument.getElementById`, `Node.ownerDocument.doctype.entities`, and `Node.ownerDocument.doctype.notations`.
[owner element]	`Attr.ownerElement`

C.4 ProcessingInstruction Node Mapping

C.4.1 Infoset to ProcessingInstruction Node

A processing instruction information item map to a ProcessingInstruction node. The attributes of the corresponding ProcessingInstruction node are constructed as follows:

Attribute	Value
`Node.nodeName`	same as `ProcessingInstruction.target`
`Node.nodeValue`	same as `ProcessingInstruction.data`
`Node.nodeType`	`Node.PROCESSING_INSTRUCTION_NODE`
`Node.parentNode`	The [parent] property
`Node.childNodes`	empty `NodeList`
`Node.firstChild`	`null`
`Node.lastChild`	`null`
`Node.previousSibling`	`null`
`Node.nextSibling`	`null`
`Node.attributes`	`null`
`Node.ownerDocument`	The document information item
`Node.namespaceURI`	`null`
`Node.prefix`	`null`
`Node.localName`	`null`
`Node.baseURI`	The [base URI] property of the parent element if any. The [base URI] property of the processing instruction information item is not exposed through the `ProcessingInstruction` node.
`Node.textContent`	same as `Node.nodeValue`
`ProcessingInstruction.target`	The [target] property
`ProcessingInstruction.data`	The [content] property

C.4.2 ProcessingInstruction Node to Infoset

A ProcessingInstruction node maps to an processing instruction information item. The properties of the corresponding processing instruction information item are constructed as follows:

Property	Value
[target]	`ProcessingInstruction.target`
[content]	`ProcessingInstruction.data`
[base URI]	`Node.baseURI` (which is equivalent to the base URI of its parent element if any)
[notation]	The `Notation` node named by the target and if available from `Node.ownerDocument.doctype.notations`
[parent]	`Node.parentNode`

C.5 EntityReference Node Mapping

C.5.1 Infoset to EntityReference Node

An unexpanded entity reference information item maps to a EntityReference node. The attributes of the corresponding EntityReference node are constructed as follows:

Attribute	Value
`Node.nodeName`	The [name] property
`Node.nodeValue`	`null`
`Node.nodeType`	`Node.ENTITY_REFERENCE_NODE`
`Node.parentNode`	the [parent] property
`Node.childNodes`	Empty `NodeList`
`Node.firstChild`	`null`
`Node.lastChild`	`null`
`Node.previousSibling`	`null`
`Node.nextSibling`	`null`
`Node.attributes`	`null`
`Node.ownerDocument`	The document information item
`Node.namespaceURI`	`null`
`Node.prefix`	`null`
`Node.localName`	`null`
`Node.baseURI`	The [declaration base URI] property
`Node.textContent`	`null` (the node has no children)

Note: The [system identifier] and [public identifier] properties are not exposed through the EntityReference node, but through the Entity node reference from this EntityReference node, if any.

C.5.2 EntityReference Node to Infoset

An EntityReference node maps to an unexpanded entity reference information item. EntityReference nodes with children (Node.childNodes contains a non-empty list) cannot be represented using the Infoset. The properties of the corresponding unexpanded entity reference information item are constructed as follows:

Property	Value
[name]	`Node.nodeName`
[system identifier]	The `Entity.systemId` value of the `Entity` node available from `Node.ownerDocument.doctype.entities` if available
[public identifier]	The `Entity.publicId` value of the `Entity` node available from `Node.ownerDocument.doctype.entities` if available
[declaration base URI]	`Node.baseURI`
[parent]	`Node.parentNode`

C.6 Text and CDATASection Nodes Mapping

Since the [XML Information Set] doesn't represent the boundaries of CDATA marked sections, CDATASection nodes cannot occur from an infoset mapping.

C.6.1 Infoset to Text Node

Consecutive character information items map to a Text node. The attributes of the corresponding Text node are constructed as follows:

Attribute/Method	Value
`Node.nodeName`	`"#text"`
`Node.nodeValue`	same as `CharacterData.data`
`Node.nodeType`	`Node.TEXT_NODE`
`Node.parentNode`	The [parent] property
`Node.childNodes`	empty `NodeList`
`Node.firstChild`	`null`
`Node.lastChild`	`null`
`Node.previousSibling`	`null`
`Node.nextSibling`	`null`
`Node.attributes`	`null`
`Node.ownerDocument`	The document information item
`Node.namespaceURI`	`null`
`Node.prefix`	`null`
`Node.localName`	`null`
`Node.baseURI`	null
`Node.textContent`	same as `Node.nodeValue`
`CharacterData.data`	A `DOMString` including all [character code] contained in the character information items
`CharacterData.length`	The number of 16-bit units needed to encode all ISO 10646 character code contained in the character information items using the UTF-16 encoding.
`Text.isElementContentWhitespace`	The [element content whitespace] property
`Text.wholeText`	same as `CharacterData.data`

Note: By construction, the values of the [parent] and [element content whitespace] properties are necessarily the sames for all consecutive character information items.

C.6.2 Text and CDATASection Nodes to Infoset

The text content of a Text or a CDATASection node maps to a sequence of character information items. The number of items is less or equal to CharacterData.length. Text nodes contained in Attr nodes are mapped to the Infoset using the Attr.value attribute. Text nodes contained in Document nodes cannot be represented using the Infoset. The properties of the corresponding character information items are constructed as follows:

Property	Value
[character code]	The ISO 10646 character code produced using one or two 16-bit units from `CharacterData.data`
[element content whitespace]	`Text.isElementContentWhitespace`
[parent]	`Node.parentNode`

C.7 Comment Node Mapping

C.7.1 Infoset to Comment Node

A comment information item maps to a Comment node. The attributes of the corresponding Comment node are constructed as follows:

Attribute	Value
`Node.nodeName`	`"#comment"`
`Node.nodeValue`	same as `CharacterData.data`
`Node.nodeType`	`Node.COMMENT_NODE`
`Node.parentNode`	The [parent] property
`Node.childNodes`	empty `NodeList`
`Node.firstChild`	`null`
`Node.lastChild`	`null`
`Node.previousSibling`	`null`
`Node.nextSibling`	`null`
`Node.attributes`	`null`
`Node.ownerDocument`	The document information item
`Node.namespaceURI`	`null`
`Node.prefix`	`null`
`Node.localName`	`null`
`Node.baseURI`	`null`
`Node.textContent`	same as `Node.nodeValue`
`CharacterData.data`	The [content] property encoded using the UTF-16 encoding.
`CharacterData.length`	The number of 16-bit units needed to encode all ISO character code contained in the [content] property using the UTF-16 encoding.

C.7.2 Comment Node to Infoset

A Comment maps to a comment information item. The properties of the corresponding comment information item are constructed as follows:

Property	Value
[content]	`CharacterData.data`
[parent]	`Node.parentNode`

C.8 DocumentType Node Mapping

C.8.1 Infoset to DocumentType Node

A document type declaration information item maps to a DocumentType node. The attributes of the corresponding DocumentType node are constructed as follows:

Attribute	Value
`Node.nodeName`	same as `DocumentType.name`
`Node.nodeValue`	`null`
`Node.nodeType`	`Node.DOCUMENT_TYPE_NODE`
`Node.parentNode`	The [parent] property
`Node.childNodes`	empty `NodeList`
`Node.firstChild`	`null`
`Node.lastChild`	`null`
`Node.previousSibling`	`null`
`Node.nextSibling`	`null`
`Node.attributes`	`null`
`Node.ownerDocument`	The document information item
`Node.namespaceURI`	`null`
`Node.prefix`	`null`
`Node.localName`	`null`
`Node.baseURI`	`null`
`Node.textContent`	`null`
`DocumentType.name`	The name of the document element.
`DocumentType.entities`	The [unparsed entities] property available from the document information item.
`DocumentType.notations`	The [notations] property available from the document information item.
`DocumentType.publicId`	The [public identifier] property
`DocumentType.systemId`	The [system identifier] property
`DocumentType.internalSubset`	The value is implementation dependent

Note: The [children] property is not exposed through the DocumentType node.

C.8.2 DocumentType Node to Infoset

A DocumentType maps to a document type declaration information item. The properties of the corresponding document type declaration information item are constructed as follows:

Property	Value
[system identifier]	`DocumentType.systemId`
[public identifier]	`DocumentType.publicId`
[children]	The value of this property is implementation dependent
[parent]	`Node.parentNode`

C.9 Entity Node Mapping

C.9.1 Infoset to Entity Node

An unparsed entity information item maps to a Entity node. The attributes of the corresponding Entity node are constructed as follows:

Attribute	Value
`Node.nodeName`	The [name] property
`Node.nodeValue`	`null`
`Node.nodeType`	`Node.ENTITY_NODE`
`Node.parentNode`	`null`
`Node.childNodes`	Empty `NodeList`
`Node.firstChild`	`null`
`Node.lastChild`	`null`
`Node.previousSibling`	`null`
`Node.nextSibling`	`null`
`Node.attributes`	`null`
`Node.ownerDocument`	The document information item
`Node.namespaceURI`	`null`
`Node.prefix`	`null`
`Node.localName`	`null`
`Node.baseURI`	The [declaration base URI] property
`Node.textContent`	`""` (the node has no children)
`Entity.publicId`	The [public identifier] property
`Entity.systemId`	The [system identifier] property
`Entity.notationName`	The [notation name] property
`Entity.inputEncoding`	`null`
`Entity.xmlEncoding`	`null`
`Entity.xmlVersion`	`null`

Note: The [notation] property is available through the DocumentType node.

C.9.2 Entity Node to Infoset

An Entity node maps to an unparsed entity information item. Entity nodes with children (Node.childNodes contains a non-empty list) cannot be represented using the Infoset. The properties of the corresponding unparsed entity information item are constructed as follows:

Property	Value
[name]	`Node.nodeName`
[system identifier]	`Entity.systemId`
[public identifier]	`Entity.publicId`
[declaration base URI]	`Node.baseURI`
[notation name]	`Entity.notationName`
[notation]	The `Notation` node referenced from `DocumentType.notations` whose name is the [notation name] property

C.10 Notation Node Mapping

C.10.1 Infoset to Notation Node

A notation information item maps to a Notation node. The attributes of the corresponding Notation node are constructed as follows:

Attribute	Value
`Node.nodeName`	The [name] property
`Node.nodeValue`	`null`
`Node.nodeType`	`Node.NOTATION_NODE`
`Node.parentNode`	`null`
`Node.childNodes`	Empty `NodeList`
`Node.firstChild`	`null`
`Node.lastChild`	`null`
`Node.previousSibling`	`null`
`Node.nextSibling`	`null`
`Node.attributes`	`null`
`Node.ownerDocument`	The document information item
`Node.namespaceURI`	`null`
`Node.prefix`	`null`
`Node.localName`	`null`
`Node.baseURI`	The [declaration base URI] property
`Node.textContent`	`null`
`Notation.publicId`	The [public identifier] property
`Notation.systemId`	The [system identifier] property

C.10.2 Notation Node to Infoset

A Notation maps to a notation information item. The properties of the corresponding notation information item are constructed as follows:

Property	Value
[name]	`Node.nodeName`
[system identifier]	`Notation.systemId`
[public identifier]	`Notation.publicId`
[parent]	`Node.parentNode`