# Interface CDATASection

All Superinterfaces:
  `CharacterData, Node, Text`

public interface CDATASection extends Text
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 split 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.

Since:
  1.4, DOM Level 2

- ## Field Summary

  ### Fields declared in interface Node

  `ATTRIBUTE_NODE, CDATA_SECTION_NODE, COMMENT_NODE, DOCUMENT_FRAGMENT_NODE, DOCUMENT_NODE, DOCUMENT_POSITION_CONTAINED_BY, DOCUMENT_POSITION_CONTAINS, DOCUMENT_POSITION_DISCONNECTED, DOCUMENT_POSITION_FOLLOWING, DOCUMENT_POSITION_IMPLEMENTATION_SPECIFIC, DOCUMENT_POSITION_PRECEDING, DOCUMENT_TYPE_NODE, ELEMENT_NODE, ENTITY_NODE, ENTITY_REFERENCE_NODE, NOTATION_NODE, PROCESSING_INSTRUCTION_NODE, TEXT_NODE`
  Modifier and Type
  Field
  Description
  `static final short`
  `ATTRIBUTE_NODE`
  The node is an `Attr`.
  `static final short`
  `CDATA_SECTION_NODE`
  The node is a `CDATASection`.
  `static final short`
  `COMMENT_NODE`
  The node is a `Comment`.
  `static final short`
  `DOCUMENT_FRAGMENT_NODE`
  The node is a `DocumentFragment`.
  `static final short`
  `DOCUMENT_NODE`
  The node is a `Document`.
  `static final short`
  `DOCUMENT_POSITION_CONTAINED_BY`
  The node is contained by the reference node.
  `static final short`
  `DOCUMENT_POSITION_CONTAINS`
  The node contains the reference node.
  `static final short`
  `DOCUMENT_POSITION_DISCONNECTED`
  The two nodes are disconnected.
  `static final short`
  `DOCUMENT_POSITION_FOLLOWING`
  The node follows the reference node.
  `static final short`
  `DOCUMENT_POSITION_IMPLEMENTATION_SPECIFIC`
  The determination of preceding versus following is implementation-specific.
  `static final short`
  `DOCUMENT_POSITION_PRECEDING`
  The second node precedes the reference node.
  `static final short`
  `DOCUMENT_TYPE_NODE`
  The node is a `DocumentType`.
  `static final short`
  `ELEMENT_NODE`
  The node is an `Element`.
  `static final short`
  `ENTITY_NODE`
  The node is an `Entity`.
  `static final short`
  `ENTITY_REFERENCE_NODE`
  The node is an `EntityReference`.
  `static final short`
  `NOTATION_NODE`
  The node is a `Notation`.
  `static final short`
  `PROCESSING_INSTRUCTION_NODE`
  The node is a `ProcessingInstruction`.
  `static final short`
  `TEXT_NODE`
  The node is a `Text` node.

- ## Method Summary

  ### Methods declared in interface CharacterData

  `appendData, deleteData, getData, getLength, insertData, replaceData, setData, substringData`
  Modifier and Type
  Method
  Description
  `void`
  `appendData(String arg)`
  Append the string to the end of the character data of the node.
  `void`
  `deleteData(int offset, int count)`
  Remove a range of 16-bit units from the node.
  `String`
  `getData()`
  The character data of the node that implements this interface.
  `int`
  `getLength()`
  The number of 16-bit units that are available through `data` and the `substringData` method below.
  `void`
  `insertData(int offset, String arg)`
  Insert a string at the specified 16-bit unit offset.
  `void`
  `replaceData(int offset, int count, String arg)`
  Replace the characters starting at the specified 16-bit unit offset with the specified string.
  `void`
  `setData(String data)`
  The character data of the node that implements this interface.
  `String`
  `substringData(int offset, int count)`
  Extracts a range of data from the node.

  ### Methods declared in interface Node

  `appendChild, cloneNode, compareDocumentPosition, getAttributes, getBaseURI, getChildNodes, getFeature, getFirstChild, getLastChild, getLocalName, getNamespaceURI, getNextSibling, getNodeName, getNodeType, getNodeValue, getOwnerDocument, getParentNode, getPrefix, getPreviousSibling, getTextContent, getUserData, hasAttributes, hasChildNodes, insertBefore, isDefaultNamespace, isEqualNode, isSameNode, isSupported, lookupNamespaceURI, lookupPrefix, normalize, removeChild, replaceChild, setNodeValue, setPrefix, setTextContent, setUserData`
  Modifier and Type
  Method
  Description
  `Node`
  `appendChild(Node newChild)`
  Adds the node `newChild` to the end of the list of children of this node.
  `Node`
  `cloneNode(boolean deep)`
  Returns a duplicate of this node, i.e., serves as a generic copy constructor for nodes.
  `short`
  `compareDocumentPosition(Node other)`
  Compares the reference node, i.e. the node on which this method is being called, with a node, i.e. the one passed as a parameter, with regard to their position in the document and according to the document order.
  `NamedNodeMap`
  `getAttributes()`
  A `NamedNodeMap` containing the attributes of this node (if it is an `Element`) or `null` otherwise.
  `String`
  `getBaseURI()`
  The absolute base URI of this node or `null` if the implementation wasn't able to obtain an absolute URI.
  `NodeList`
  `getChildNodes()`
  A `NodeList` that contains all children of this node.
  `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 .
  `Node`
  `getFirstChild()`
  The first child of this node.
  `Node`
  `getLastChild()`
  The last child of this node.
  `String`
  `getLocalName()`
  Returns the local part of the qualified name of this node.
  `String`
  `getNamespaceURI()`
  The namespace URI of this node, or `null` if it is unspecified (see ).
  `Node`
  `getNextSibling()`
  The node immediately following this node.
  `String`
  `getNodeName()`
  The name of this node, depending on its type; see the table above.
  `short`
  `getNodeType()`
  A code representing the type of the underlying object, as defined above.
  `String`
  `getNodeValue()`
  The value of this node, depending on its type; see the table above.
  `Document`
  `getOwnerDocument()`
  The `Document` object associated with this node.
  `Node`
  `getParentNode()`
  The parent of this node.
  `String`
  `getPrefix()`
  The namespace prefix of this node, or `null` if it is unspecified.
  `Node`
  `getPreviousSibling()`
  The node immediately preceding this node.
  `String`
  `getTextContent()`
  This attribute returns the text content of this node and its descendants.
  `Object`
  `getUserData(String key)`
  Retrieves the object associated to a key on a this node.
  `boolean`
  `hasAttributes()`
  Returns whether this node (if it is an element) has any attributes.
  `boolean`
  `hasChildNodes()`
  Returns whether this node has any children.
  `Node`
  `insertBefore(Node newChild, Node refChild)`
  Inserts the node `newChild` before the existing child node `refChild`.
  `boolean`
  `isDefaultNamespace(String namespaceURI)`
  This method checks if the specified `namespaceURI` is the default namespace or not.
  `boolean`
  `isEqualNode(Node arg)`
  Tests whether two nodes are equal.
  `boolean`
  `isSameNode(Node other)`
  Returns whether this node is the same node as the given one.
  `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 .
  `String`
  `lookupNamespaceURI(String prefix)`
  Look up the namespace URI associated to the given prefix, starting from this node.
  `String`
  `lookupPrefix(String namespaceURI)`
  Look up the prefix associated to the given namespace URI, starting from this node.
  `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.
  `Node`
  `removeChild(Node oldChild)`
  Removes the child node indicated by `oldChild` from the list of children, and returns it.
  `Node`
  `replaceChild(Node newChild, Node oldChild)`
  Replaces the child node `oldChild` with `newChild` in the list of children, and returns the `oldChild` node.
  `void`
  `setNodeValue(String nodeValue)`
  The value of this node, depending on its type; see the table above.
  `void`
  `setPrefix(String prefix)`
  The namespace prefix of this node, or `null` if it is unspecified.
  `void`
  `setTextContent(String textContent)`
  This attribute returns the text content of this node and its descendants.
  `Object`
  `setUserData(String key, Object data, UserDataHandler handler)`
  Associate an object to a key on this node.

  ### Methods declared in interface Text

  `getWholeText, isElementContentWhitespace, replaceWholeText, splitText`
  Modifier and Type
  Method
  Description
  `String`
  `getWholeText()`
  Returns all text of `Text` nodes logically-adjacent text nodes to this node, concatenated in document order.
  `boolean`
  `isElementContentWhitespace()`
  Returns whether this text node contains element content whitespace, often abusively called "ignorable whitespace".
  `Text`
  `replaceWholeText(String content)`
  Replaces the text of the current node and all logically-adjacent text nodes with the specified text.
  `Text`
  `splitText(int offset)`
  Breaks this node into two nodes at the specified `offset`, keeping both in the tree as siblings.