Class XPathFactory

java.lang.Object

javax.xml.xpath.XPathFactory

public abstract class XPathFactory
extends Object

An XPathFactory instance can be used to create XPath objects.

See newInstance(String uri) for lookup mechanism.

The XPathFactory class is not thread-safe. In other words, it is the application's responsibility to ensure that at most one thread is using a XPathFactory object at any given moment. Implementations are encouraged to mark methods as synchronized to protect themselves from broken clients.

XPathFactory is not re-entrant. While one of the newInstance methods is being invoked, applications may not attempt to recursively invoke a newInstance method, even from the same thread.

Since:

1.5

Field Summary

Fields

Modifier and Type	Field	Description
static final String	DEFAULT_OBJECT_MODEL_URI	Default Object Model URI.
static final String	DEFAULT_PROPERTY_NAME	The default property name according to the JAXP spec.

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	XPathFactory()	Protected constructor as newInstance() or newInstance(String uri) or newInstance(String uri, String factoryClassName, ClassLoader classLoader) should be used to create a new instance of an XPathFactory.

Method Summary

Modifier and Type	Method	Description
abstract boolean	getFeature(String name)	Get the state of the named feature.
String	getProperty(String name)	Returns the value of the specified property.
abstract boolean	isObjectModelSupported(String objectModel)	Is specified object model supported by this XPathFactory?
static XPathFactory	newDefaultInstance()	Creates a new instance of the XPathFactory builtin system-default implementation.
static XPathFactory	newInstance()	Get a new XPathFactory instance using the default object model, DEFAULT_OBJECT_MODEL_URI, the W3C DOM.
static XPathFactory	newInstance(String uri)	Obtains a new XPathFactory instance using the specified object model.
static XPathFactory	newInstance(String uri, String factoryClassName, ClassLoader classLoader)	Obtain a new instance of a XPathFactory from a factory class name.
abstract XPath	newXPath()	Return a new XPath using the underlying object model determined when the XPathFactory was instantiated.
abstract void	setFeature(String name, boolean value)	Sets a feature for this XPathFactory.
void	setProperty(String name, String value)	Sets a property for this XPathFactory.
abstract void	setXPathFunctionResolver(XPathFunctionResolver resolver)	Establish a default function resolver.
abstract void	setXPathVariableResolver(XPathVariableResolver resolver)	Establish a default variable resolver.

Methods declared in class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

DEFAULT_PROPERTY_NAME

public static final String DEFAULT_PROPERTY_NAME

The default property name according to the JAXP spec.

See Also:

• Constant Field Values

DEFAULT_OBJECT_MODEL_URI

public static final String DEFAULT_OBJECT_MODEL_URI

Default Object Model URI.

See Also:

• Constant Field Values

Constructor Details

XPathFactory

protected XPathFactory()

Protected constructor as newInstance() or newInstance(String uri) or newInstance(String uri, String factoryClassName, ClassLoader classLoader) should be used to create a new instance of an XPathFactory.

Method Details

newDefaultInstance

public static XPathFactory newDefaultInstance()

Creates a new instance of the XPathFactory builtin system-default implementation.

Implementation Requirements:

The XPathFactory builtin system-default implementation is only required to support the default object model, the W3C DOM, but may support additional object models.

Returns:

A new instance of the XPathFactory builtin system-default implementation.

Since:

9

newInstance

public static XPathFactory newInstance()

Get a new XPathFactory instance using the default object model, DEFAULT_OBJECT_MODEL_URI, the W3C DOM.

This method is functionally equivalent to:

   newInstance(DEFAULT_OBJECT_MODEL_URI)
 

Since the implementation for the W3C DOM is always available, this method will never fail.

Returns:

Instance of an XPathFactory.

Throws:

RuntimeException - When there is a failure in creating an XPathFactory for the default object model.

newInstance

public static XPathFactory newInstance(String uri)
                                throws XPathFactoryConfigurationException

Obtains a new XPathFactory instance using the specified object model. This method uses the JAXP Lookup Mechanism to determine and load the XPathFactory implementation that supports the specified object model.

Tip for Trouble-shooting:

See Properties.load(java.io.InputStream) for exactly how a property file is parsed. In particular, colons ':' need to be escaped in a property file, so make sure the URIs are properly escaped in it. For example:

   http\://java.sun.com/jaxp/xpath/dom=org.acme.DomXPathFactory
 

Parameters:

uri - Identifies the underlying object model. The specification only defines the URI DEFAULT_OBJECT_MODEL_URI, http://java.sun.com/jaxp/xpath/dom for the W3C DOM, the org.w3c.dom package, and implementations are free to introduce other URIs for other object models.

Returns:

Instance of an XPathFactory.

Throws:

XPathFactoryConfigurationException - If the specified object model is unavailable, or if there is a configuration error.

NullPointerException - If uri is null.

IllegalArgumentException - If uri is null or uri.length() == 0.

newInstance

public static XPathFactory newInstance(String uri,
 String factoryClassName,