CDATA sections are used to escape blocks of text containing characters that would otherwise be regarded as markup. The only delimiter that is recognized in a CDATA section is the "]]>" string that ends the CDATA section. CDATA sections cannot be nested. Their primary purpose is for including material such as XML fragments, without needing to escape all the delimiters.
The CharacterData.data
attribute holds the text that is
contained by the CDATA section. Note that this may contain characters that need to be escaped outside of CDATA sections and
that, depending on the character encoding ("charset") chosen for
serialization, it may be impossible to write out some characters as part
of a CDATA section.
The CDATASection
interface inherits from the
CharacterData
interface through the Text
interface. Adjacent CDATASection
nodes are not merged by use
of the normalize
method of the Node
interface.
No lexical check is done on the content of a CDATA section and it is
therefore possible to have the character sequence "]]>"
in the content, which is illegal in a CDATA section per section 2.7 of [XML 1.0]. The
presence of this character sequence must generate a fatal error during
serialization or the cdata section must be splitted before the
serialization (see also the parameter "split-cdata-sections"
in the DOMConfiguration
interface).
Note: Because no markup is recognized within a
CDATASection
, character numeric references cannot be used as
an escape mechanism when serializing. Therefore, action needs to be taken
when serializing a CDATASection
with a character encoding
where some of the contained characters cannot be represented. Failure to
do so would not produce well-formed XML.
Note: One potential solution in the serialization process is to end the CDATA section before the character, output the character using a character reference or entity reference, and open a new CDATA section for any further characters in the text node. Note, however, that some code conversion libraries at the time of writing do not return an error or exception when a character is missing from the encoding, making the task of ensuring that data is not corrupted on serialization more difficult.
See also the Document Object Model (DOM) Level 3 Core Specification.
Inherited Constant Summary
short | ATTRIBUTE_NODE | The node is an Attr . |
short | CDATA_SECTION_NODE | The node is a CDATASection . |
short | COMMENT_NODE | The node is a Comment . |
short | DOCUMENT_FRAGMENT_NODE | The node is a DocumentFragment . |
short | DOCUMENT_NODE | The node is a Document . |
short | DOCUMENT_POSITION_CONTAINED_BY | The node is contained by the reference node. |
short | DOCUMENT_POSITION_CONTAINS | The node contains the reference node. |
short | DOCUMENT_POSITION_DISCONNECTED | The two nodes are disconnected. |
short | DOCUMENT_POSITION_FOLLOWING | The node follows the reference node. |
short | DOCUMENT_POSITION_IMPLEMENTATION_SPECIFIC | The determination of preceding versus following is implementation-specific. |
short | DOCUMENT_POSITION_PRECEDING | The second node precedes the reference node. |
short | DOCUMENT_TYPE_NODE | The node is a DocumentType . |
short | ELEMENT_NODE | The node is an Element . |
short | ENTITY_NODE | The node is an Entity . |
short | ENTITY_REFERENCE_NODE | The node is an EntityReference . |
short | NOTATION_NODE | The node is a Notation . |
short | PROCESSING_INSTRUCTION_NODE | The node is a ProcessingInstruction . |
short | TEXT_NODE | The node is a Text node. |
Inherited Method Summary
abstract String |
getWholeText()
Returns all text of
Text nodes logically-adjacent text
nodes to this node, concatenated in document order. |
abstract boolean |
isElementContentWhitespace()
Returns whether this text node contains
element content whitespace, often abusively called "ignorable whitespace".
|
abstract Text |
replaceWholeText(String content)
Replaces the text of the current node and all logically-adjacent text
nodes with the specified text.
|
abstract Text |
splitText(int offset)
Breaks this node into two nodes at the specified
offset ,
keeping both in the tree as siblings. |
abstract void | |
abstract void |
deleteData(int offset, int count)
Remove a range of 16-bit units from the node.
|
abstract String |
getData()
The character data of the node that implements this interface.
|
abstract int |
getLength()
The number of 16-bit units that are available through
data
and the substringData method below. |
abstract void | |
abstract void |
replaceData(int offset, int count, String arg)
Replace the characters starting at the specified 16-bit unit offset
with the specified string.
|
abstract void | |
abstract String |
substringData(int offset, int count)
Extracts a range of data from the node.
|
abstract Node | |
abstract Node |
cloneNode(boolean deep)
Returns a duplicate of this node, i.e., serves as a generic copy
constructor for nodes.
|
abstract short | |
abstract NamedNodeMap |
getAttributes()
A
NamedNodeMap containing the attributes of this node (if
it is an Element ) or null otherwise. |
abstract String |
getBaseURI()
The absolute base URI of this node or
null if the
implementation wasn't able to obtain an absolute URI. |
abstract NodeList |
getChildNodes()
A
NodeList that contains all children of this node. |
abstract Object |
getFeature(String feature, String version)
This method returns a specialized object which implements the
specialized APIs of the specified feature and version, as specified
in .
|
abstract Node |
getFirstChild()
The first child of this node.
|
abstract Node |
getLastChild()
The last child of this node.
|
abstract String |
getLocalName()
Returns the local part of the qualified name of this node.
|
abstract String |
getNamespaceURI()
The namespace URI of this node, or
null if it is
unspecified (see ). |
abstract Node |
getNextSibling()
The node immediately following this node.
|
abstract String |
getNodeName()
The name of this node, depending on its type; see the table above.
|
abstract short |
getNodeType()
A code representing the type of the underlying object, as defined above.
|
abstract String |
getNodeValue()
The value of this node, depending on its type; see the table above.
|
abstract Document |
getOwnerDocument()
The
Document object associated with this node. |
abstract Node |
getParentNode()
The parent of this node.
|
abstract String |
getPrefix()
The namespace prefix of this node, or
null if it is
unspecified. |
abstract Node |
getPreviousSibling()
The node immediately preceding this node.
|
abstract String |
getTextContent()
This attribute returns the text content of this node and its
descendants.
|
abstract Object | |
abstract boolean |
hasAttributes()
Returns whether this node (if it is an element) has any attributes.
|
abstract boolean |
hasChildNodes()
Returns whether this node has any children.
|
abstract Node |
insertBefore(Node newChild, Node refChild)
Inserts the node
newChild before the existing child node
refChild . |
abstract boolean |
isDefaultNamespace(String namespaceURI)
This method checks if the specified
namespaceURI is the
default namespace or not. |
abstract boolean | |
abstract boolean | |
abstract boolean |
isSupported(String feature, String version)
Tests whether the DOM implementation implements a specific feature and
that feature is supported by this node, as specified in .
|
abstract String |
lookupNamespaceURI(String prefix)
Look up the namespace URI associated to the given prefix, starting from
this node.
|
abstract String |
lookupPrefix(String namespaceURI)
Look up the prefix associated to the given namespace URI, starting from
this node.
|
abstract void |
normalize()
Puts all
Text nodes in the full depth of the sub-tree
underneath this Node , including attribute nodes, into a
"normal" form where only structure (e.g., elements, comments,
processing instructions, CDATA sections, and entity references)
separates Text nodes, i.e., there are neither adjacent
Text nodes nor empty Text nodes. |
abstract Node |
removeChild(Node oldChild)
Removes the child node indicated by
oldChild from the list
of children, and returns it. |
abstract Node |
replaceChild(Node newChild, Node oldChild)
Replaces the child node
oldChild with newChild
in the list of children, and returns the oldChild node. |
abstract void | |
abstract void | |
abstract void |
setTextContent(String textContent)
This attribute returns the text content of this node and its
descendants.
|
abstract Object |
setUserData(String key, Object data, UserDataHandler handler)
Associate an object to a key on this node.
|