XPathEvaluator. In a DOM implementation which supports the
XPath 3.0 feature, as described above, the XPathEvaluator
interface will be implemented on the same object which implements the
Document interface permitting it to be obtained by the usual
binding-specific method such as casting or by using the DOM Level 3
getInterface method. In this case the implementation obtained from the
Document supports the XPath DOM module and is compatible with the XPath
1.0 specification.
Evaluation of expressions with specialized extension functions or
variables may not work in all implementations and is, therefore, not
portable. XPathEvaluator implementations may be available
from other sources that could provide specific support for specialized
extension functions or variables as would be defined by other
specifications.
See also the Document Object Model (DOM) Level 3 XPath Specification.
| Modifier and Type | Method and Description |
|---|---|
| public XPathExpression | Returns: The compiled form of the XPath expression.The XPath expression string to be parsed. expression, XPathNSResolver The resolver)resolver permits translation of
prefixes within the XPath expression into appropriate namespace URIs
. If this is specified as null, any namespace prefix
within the expression will result in DOMException
being thrown with the code NAMESPACE_ERR.Creates a parsed XPath expression with resolved namespaces. |
| public XPathNSResolver | Returns: XPathNSResolver which resolves namespaces with
respect to the definitions in scope for a specified node.The node to be used as a context for namespace
resolution. nodeResolver)Adapts any DOM node to resolve namespaces so that an XPath expression can be easily evaluated relative to the context of the node where it appeared within the document. |
| public Object | Returns: The result of the evaluation of the XPath expression.For XPath 1.0 results, this object will be of typeXPathResult.The XPath expression string to be parsed and
evaluated. expression, Node The contextNode, XPathNSResolver context is context node for the
evaluation of this XPath expression. If the XPathEvaluator was
obtained by casting the Document then this must be
owned by the same document and must be a Document,
Element, Attribute, Text,
CDATASection, Comment,
ProcessingInstruction, or XPathNamespace
node. If the context node is a Text or a
CDATASection, then the context is interpreted as the
whole logical text node as seen by XPath, unless the node is empty
in which case it may not serve as the XPath context.The resolver, short resolver permits translation of
prefixes within the XPath expression into appropriate namespace URIs
. If this is specified as null, any namespace prefix
within the expression will result in DOMException
being thrown with the code NAMESPACE_ERR.If a specific type, Object type is specified, then the
result will be returned as the corresponding type.For XPath 1.0
results, this must be one of the codes of the
XPathResult interface.The result)result specifies a specific result
object which may be reused and returned by this method. If this is
specified as nullor the implementation does not reuse
the specified result, a new result object will be constructed and
returned.For XPath 1.0 results, this object will be of type
XPathResult.Evaluates an XPath expression string and returns a result of the specified type if possible. |
| createExpression | back to summary |
|---|---|
| public XPathExpression createExpression(String expression, XPathNSResolver resolver) throws XPathException, DOMException Creates a parsed XPath expression with resolved namespaces. This is useful when an expression will be reused in an application since it makes it possible to compile the expression string into a more efficient internal form and preresolve all namespace prefixes which occur within the expression.
| |
| createNSResolver | back to summary |
|---|---|
| public XPathNSResolver createNSResolver(Node nodeResolver) Adapts any DOM node to resolve namespaces so that an XPath expression
can be easily evaluated relative to the context of the node where it
appeared within the document. This adapter works like the DOM Level 3
method
| |
| evaluate | back to summary |
|---|---|
| public Object evaluate(String expression, Node contextNode, XPathNSResolver resolver, short type, Object result) throws XPathException, DOMException Evaluates an XPath expression string and returns a result of the specified type if possible.
| |