Java in a Nutshell, 5th Edition [Electronic resources] نسخه متنی

The XPathFactory class is
a factory for creating XPath expression
evaluators. Call the no-argument version of newInstance(
) to obtain an XPathFactory object that
creates XPath object to work with DOM documents.
The javax.xml.xpath package is nominally
object-model independent, however, and you can specify the name of a
different object model by calling the one-argument version of
newInstance( ).

Once you have created an XPathFactory object, you
can set default function and variable resolvers with
setXPathFunctionResolver(
) and setXPathVariableResolver(
). You can configure implementation-dependent features of
an XPathFactory with setFeature(
). All
implementations are required to support the
XMLConstants.FEATURE_SECURE_PROCESSING feature.
When this feature is set to true, external functions are not allowed
in XPath expressions, and the
XPathFunctionResolver is not used.

After creating and configuring an XPathFactory
object, use the newXPath( ) method to create one
or more XPath objects for actually evaluating
XPath expressions.

public abstract class

XPathFactory {
// Protected Constructors
protected

XPathFactory ( );
// Public Constants
public static final String

DEFAULT_OBJECT_MODEL_URI ; ="http://java.sun.com/jaxp/xpath/dom"
public static final String

DEFAULT_PROPERTY_NAME ; ="javax.xml.xpath.XPathFactory"
// Public Class Methods
public static final XPathFactory

newInstance ( );
public static final XPathFactory

newInstance (String

uri )
throws XPathFactoryConfigurationException;
// Public Instance Methods
public abstract boolean

getFeature (String

name )
throws XPathFactoryConfigurationException;
public abstract boolean

isObjectModelSupported (String

objectModel );
public abstract XPath

newXPath ( );
public abstract void

setFeature (String

name , boolean

value )
throws XPathFactoryConfigurationException;
public abstract void

setXPathFunctionResolver (XPathFunctionResolver

resolver );
public abstract void

setXPathVariableResolver (XPathVariableResolver

resolver );
}