Interface Element
- All Superinterfaces:
Node
- All Known Subinterfaces:
-
HTMLAnchorElement
,HTMLAppletElement
,HTMLAreaElement
,HTMLBaseElement
,HTMLBaseFontElement
,HTMLBodyElement
,HTMLBRElement
,HTMLButtonElement
,HTMLDirectoryElement
,HTMLDivElement
,HTMLDListElement
,HTMLElement
,HTMLFieldSetElement
,HTMLFontElement
,HTMLFormElement
,HTMLFrameElement
,HTMLFrameSetElement
,HTMLHeadElement
,HTMLHeadingElement
,HTMLHRElement
,HTMLHtmlElement
,HTMLIFrameElement
,HTMLImageElement
,HTMLInputElement
,HTMLIsIndexElement
,HTMLLabelElement
,HTMLLegendElement
,HTMLLIElement
,HTMLLinkElement
,HTMLMapElement
,HTMLMenuElement
,HTMLMetaElement
,HTMLModElement
,HTMLObjectElement
,HTMLOListElement
,HTMLOptGroupElement
,HTMLOptionElement
,HTMLParagraphElement
,HTMLParamElement
,HTMLPreElement
,HTMLQuoteElement
,HTMLScriptElement
,HTMLSelectElement
,HTMLStyleElement
,HTMLTableCaptionElement
,HTMLTableCellElement
,HTMLTableColElement
,HTMLTableElement
,HTMLTableRowElement
,HTMLTableSectionElement
,HTMLTextAreaElement
,HTMLTitleElement
,HTMLUListElement
- All Known Implementing Classes:
IIOMetadataNode
public interface Element extends Node
The Element
interface represents an element in an HTML or XML document. Elements may have attributes associated with them; since the Element
interface inherits from Node
, the generic Node
interface attribute attributes
may be used to retrieve the set of all attributes for an element. There are methods on the Element
interface to retrieve either an Attr
object by name or an attribute value by name. In XML, where an attribute value may contain entity references, an Attr
object should be retrieved to examine the possibly fairly complex sub-tree representing the attribute value. On the other hand, in HTML, where all attributes have simple string values, methods to directly access an attribute value can safely be used as a convenience.
Note: In DOM Level 2, the method normalize
is inherited from the Node
interface where it was moved.
See also the Document Object Model (DOM) Level 3 Core Specification.
Field Summary
Fields declared in interface org.w3c.dom.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
Method Summary
Modifier and Type | Method | Description |
---|---|---|
String | getAttribute(String name) | Retrieves an attribute value by name. |
Attr | getAttributeNode(String name) | Retrieves an attribute node by name. |
Attr | getAttributeNodeNS(String namespaceURI,
String localName) | Retrieves an |
String | getAttributeNS(String namespaceURI,
String localName) | Retrieves an attribute value by local name and namespace URI. |
NodeList | getElementsByTagName(String name) | Returns a |
NodeList | getElementsByTagNameNS(String namespaceURI,
String localName) | Returns a |
TypeInfo | getSchemaTypeInfo() | The type information associated with this element. |
String | getTagName() | The name of the element. |
boolean | hasAttribute(String name) | Returns |
boolean | hasAttributeNS(String namespaceURI,
String localName) | Returns |
void | removeAttribute(String name) | Removes an attribute by name. |
Attr | removeAttributeNode(Attr oldAttr) | Removes the specified attribute node. |
void | removeAttributeNS(String namespaceURI,
String localName) | Removes an attribute by local name and namespace URI. |
void | setAttribute(String name,
String value) | Adds a new attribute. |
Attr | setAttributeNode(Attr newAttr) | Adds a new attribute node. |
Attr | setAttributeNodeNS(Attr newAttr) | Adds a new attribute. |
void | setAttributeNS(String namespaceURI,
String qualifiedName,
String value) | Adds a new attribute. |
void | setIdAttribute(String name,
boolean isId) | If the parameter |
void | setIdAttributeNode(Attr idAttr,
boolean isId) | If the parameter |
void | setIdAttributeNS(String namespaceURI,
String localName,
boolean isId) | If the parameter |
Methods declared in interface org.w3c.dom.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
Method Detail
getTagName
String getTagName()
The name of the element. If Node.localName
is different from null
, this attribute is a qualified name. For example, in:
<elementExample id="demo"> ... </elementExample> ,
tagName
has the value "elementExample"
. Note that this is case-preserving in XML, as are all of the operations of the DOM. The HTML DOM returns the tagName
of an HTML element in the canonical uppercase form, regardless of the case in the source HTML document. getAttribute
String getAttribute(String name)
Retrieves an attribute value by name.
- Parameters:
-
name
- The name of the attribute to retrieve. - Returns:
- The
Attr
value as a string, or the empty string if that attribute does not have a specified or default value.
setAttribute
void setAttribute(String name, String value) throws DOMException
Adds a new attribute. If an attribute with that name is already present in the element, its value is changed to be that of the value parameter. This value is a simple string; it is not parsed as it is being set. So any markup (such as syntax to be recognized as an entity reference) is treated as literal text, and needs to be appropriately escaped by the implementation when it is written out. In order to assign an attribute value that contains entity references, the user must create an Attr
node plus any Text
and EntityReference
nodes, build the appropriate subtree, and use setAttributeNode
to assign it as the value of an attribute.
To set an attribute with a qualified name and namespace URI, use the setAttributeNS
method.
- Parameters:
-
name
- The name of the attribute to create or alter. -
value
- Value to set in string form. - Throws:
-
DOMException
- INVALID_CHARACTER_ERR: Raised if the specified name is not an XML name according to the XML version in use specified in theDocument.xmlVersion
attribute.
NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly.
removeAttribute
void removeAttribute(String name) throws DOMException
Removes an attribute by name. If a default value for the removed attribute is defined in the DTD, a new attribute immediately appears with the default value as well as the corresponding namespace URI, local name, and prefix when applicable. The implementation may handle default values from other schemas similarly but applications should use Document.normalizeDocument()
to guarantee this information is up-to-date.
If no attribute with this name is found, this method has no effect.
To remove an attribute by local name and namespace URI, use the removeAttributeNS
method.
- Parameters:
-
name
- The name of the attribute to remove. - Throws:
-
DOMException
- NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly.
getAttributeNode
Attr getAttributeNode(String name)
Retrieves an attribute node by name.
To retrieve an attribute node by qualified name and namespace URI, use the getAttributeNodeNS
method.
- Parameters:
-
name
- The name (nodeName
) of the attribute to retrieve. - Returns:
- The
Attr
node with the specified name (nodeName
) ornull
if there is no such attribute.
setAttributeNode
Attr setAttributeNode(Attr newAttr) throws DOMException
Adds a new attribute node. If an attribute with that name ( nodeName
) is already present in the element, it is replaced by the new one. Replacing an attribute node by itself has no effect.
To add a new attribute node with a qualified name and namespace URI, use the setAttributeNodeNS
method.
- Parameters:
-
newAttr
- TheAttr
node to add to the attribute list. - Returns:
- If the
newAttr
attribute replaces an existing attribute, the replacedAttr
node is returned, otherwisenull
is returned. - Throws:
-
DOMException
- WRONG_DOCUMENT_ERR: Raised ifnewAttr
was created from a different document than the one that created the element.
NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly.
INUSE_ATTRIBUTE_ERR: Raised ifnewAttr
is already an attribute of anotherElement
object. The DOM user must explicitly cloneAttr
nodes to re-use them in other elements.
removeAttributeNode
Attr removeAttributeNode(Attr oldAttr) throws DOMException
Removes the specified attribute node. If a default value for the removed Attr
node is defined in the DTD, a new node immediately appears with the default value as well as the corresponding namespace URI, local name, and prefix when applicable. The implementation may handle default values from other schemas similarly but applications should use Document.normalizeDocument()
to guarantee this information is up-to-date.
- Parameters:
-
oldAttr
- TheAttr
node to remove from the attribute list. - Returns:
- The
Attr
node that was removed. - Throws:
-
DOMException
- NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly.
NOT_FOUND_ERR: Raised ifoldAttr
is not an attribute of the element.
getElementsByTagName
NodeList getElementsByTagName(String name)
Returns a NodeList
of all descendant Elements
with a given tag name, in document order.
- Parameters:
-
name
- The name of the tag to match on. The special value "*" matches all tags. - Returns:
- A list of matching
Element
nodes.
getAttributeNS
String getAttributeNS(String namespaceURI, String localName) throws DOMException
Retrieves an attribute value by local 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
- The namespace URI of the attribute to retrieve. -
localName
- The local name of the attribute to retrieve. - Returns:
- The
Attr
value as a string, or the empty string if that attribute does not have a specified or default value. - Throws:
-
DOMException
- 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]). - Since:
- 1.4, DOM Level 2
setAttributeNS
void setAttributeNS(String namespaceURI, String qualifiedName, String value) throws DOMException
Adds a new attribute. If an attribute with the same local name and namespace URI is already present on the element, its prefix is changed to be the prefix part of the qualifiedName
, and its value is changed to be the value
parameter. This value is a simple string; it is not parsed as it is being set. So any markup (such as syntax to be recognized as an entity reference) is treated as literal text, and needs to be appropriately escaped by the implementation when it is written out. In order to assign an attribute value that contains entity references, the user must create an Attr
node plus any Text
and EntityReference
nodes, build the appropriate subtree, and use setAttributeNodeNS
or setAttributeNode
to assign it as the value of an attribute.
Per [XML Namespaces] , applications must use the value null
as the namespaceURI
parameter for methods if they wish to have no namespace.
- Parameters:
-
namespaceURI
- The namespace URI of the attribute to create or alter. -
qualifiedName
- The qualified name of the attribute to create or alter. -
value
- The value to set in string form. - Throws:
-
DOMException
- INVALID_CHARACTER_ERR: Raised if the specified qualified name is not an XML name according to the XML version in use specified in theDocument.xmlVersion
attribute.
NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly.
NAMESPACE_ERR: Raised if thequalifiedName
is malformed per the Namespaces in XML specification, if thequalifiedName
has a prefix and thenamespaceURI
isnull
, if thequalifiedName
has a prefix that is "xml" and thenamespaceURI
is different from " http://www.w3.org/XML/1998/namespace", if thequalifiedName
or its prefix is "xmlns" and thenamespaceURI
is different from "http://www.w3.org/2000/xmlns/", or if thenamespaceURI
is "http://www.w3.org/2000/xmlns/" and neither thequalifiedName
nor its prefix is "xmlns".
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]). - Since:
- 1.4, DOM Level 2
removeAttributeNS
void removeAttributeNS(String namespaceURI, String localName) throws DOMException
Removes an attribute by local name and namespace URI. If a default value for the removed attribute is defined in the DTD, a new attribute immediately appears with the default value as well as the corresponding namespace URI, local name, and prefix when applicable. The implementation may handle default values from other schemas similarly but applications should use Document.normalizeDocument()
to guarantee this information is up-to-date.
If no attribute with this local name and namespace URI is found, this method has no effect.
Per [XML Namespaces] , applications must use the value null
as the namespaceURI
parameter for methods if they wish to have no namespace.
- Parameters:
-
namespaceURI
- The namespace URI of the attribute to remove. -
localName
- The local name of the attribute to remove. - Throws:
-
DOMException
- NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly.
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]). - Since:
- 1.4, DOM Level 2
getAttributeNodeNS
Attr getAttributeNodeNS(String namespaceURI, String localName) throws DOMException
Retrieves an Attr
node by local 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
- The namespace URI of the attribute to retrieve. -
localName
- The local name of the attribute to retrieve. - Returns:
- The
Attr
node with the specified attribute local name and namespace URI ornull
if there is no such attribute. - Throws:
-
DOMException
- 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]). - Since:
- 1.4, DOM Level 2
setAttributeNodeNS
Attr setAttributeNodeNS(Attr newAttr) throws DOMException
Adds a new attribute. If an attribute with that local name and that namespace URI is already present in the element, it is replaced by the new one. Replacing an attribute node by itself has no effect.
Per [XML Namespaces] , applications must use the value null
as the namespaceURI
parameter for methods if they wish to have no namespace.
- Parameters:
-
newAttr
- TheAttr
node to add to the attribute list. - Returns:
- If the
newAttr
attribute replaces an existing attribute with the same local name and namespace URI, the replacedAttr
node is returned, otherwisenull
is returned. - Throws:
-
DOMException
- WRONG_DOCUMENT_ERR: Raised ifnewAttr
was created from a different document than the one that created the element.
NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly.
INUSE_ATTRIBUTE_ERR: Raised ifnewAttr
is already an attribute of anotherElement
object. The DOM user must explicitly cloneAttr
nodes to re-use them in other elements.
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]). - Since:
- 1.4, DOM Level 2
getElementsByTagNameNS
NodeList getElementsByTagNameNS(String namespaceURI, String localName) throws DOMException
Returns a NodeList
of all the descendant Elements
with a given local name and namespace URI in document order.
- Parameters:
-
namespaceURI
- The namespace URI of the elements to match on. The special value "*" matches all namespaces. -
localName
- The local name of the elements to match on. The special value "*" matches all local names. - Returns:
- A new
NodeList
object containing all the matchedElements
. - Throws:
-
DOMException
- 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]). - Since:
- 1.4, DOM Level 2
hasAttribute
boolean hasAttribute(String name)
Returns true
when an attribute with a given name is specified on this element or has a default value, false
otherwise.
- Parameters:
-
name
- The name of the attribute to look for. - Returns:
-
true
if an attribute with the given name is specified on this element or has a default value,false
otherwise. - Since:
- 1.4, DOM Level 2
hasAttributeNS
boolean hasAttributeNS(String namespaceURI, String localName) throws DOMException
Returns true
when an attribute with a given local name and namespace URI is specified on this element or has a default value, false
otherwise.
Per [XML Namespaces] , applications must use the value null
as the namespaceURI
parameter for methods if they wish to have no namespace.
- Parameters:
-
namespaceURI
- The namespace URI of the attribute to look for. -
localName
- The local name of the attribute to look for. - Returns:
-
true
if an attribute with the given local name and namespace URI is specified or has a default value on this element,false
otherwise. - Throws:
-
DOMException
- 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]). - Since:
- 1.4, DOM Level 2
getSchemaTypeInfo
TypeInfo getSchemaTypeInfo()
The type information associated with this element.
- Since:
- 1.5, DOM Level 3
setIdAttribute
void setIdAttribute(String name, boolean isId) throws DOMException
If the parameter isId
is true
, this method declares the specified attribute to be a user-determined ID attribute . This affects the value of Attr.isId
and the behavior of Document.getElementById
, but does not change any schema that may be in use, in particular this does not affect the Attr.schemaTypeInfo
of the specified Attr
node. Use the value false
for the parameter isId
to undeclare an attribute for being a user-determined ID attribute.
To specify an attribute by local name and namespace URI, use the setIdAttributeNS
method.
- Parameters:
-
name
- The name of the attribute. -
isId
- Whether the attribute is a of type ID. - Throws:
-
DOMException
- NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly.
NOT_FOUND_ERR: Raised if the specified node is not an attribute of this element. - Since:
- 1.5, DOM Level 3
setIdAttributeNS
void setIdAttributeNS(String namespaceURI, String localName, boolean isId) throws DOMException
If the parameter isId
is true
, this method declares the specified attribute to be a user-determined ID attribute . This affects the value of Attr.isId
and the behavior of Document.getElementById
, but does not change any schema that may be in use, in particular this does not affect the Attr.schemaTypeInfo
of the specified Attr
node. Use the value false
for the parameter isId
to undeclare an attribute for being a user-determined ID attribute.
- Parameters:
-
namespaceURI
- The namespace URI of the attribute. -
localName
- The local name of the attribute. -
isId
- Whether the attribute is a of type ID. - Throws:
-
DOMException
- NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly.
NOT_FOUND_ERR: Raised if the specified node is not an attribute of this element. - Since:
- 1.5, DOM Level 3
setIdAttributeNode
void setIdAttributeNode(Attr idAttr, boolean isId) throws DOMException
If the parameter isId
is true
, this method declares the specified attribute to be a user-determined ID attribute . This affects the value of Attr.isId
and the behavior of Document.getElementById
, but does not change any schema that may be in use, in particular this does not affect the Attr.schemaTypeInfo
of the specified Attr
node. Use the value false
for the parameter isId
to undeclare an attribute for being a user-determined ID attribute.
- Parameters:
-
idAttr
- The attribute node. -
isId
- Whether the attribute is a of type ID. - Throws:
-
DOMException
- NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly.
NOT_FOUND_ERR: Raised if the specified node is not an attribute of this element. - Since:
- 1.5, DOM Level 3