net.sf.saxon.sxpath
Class XPathEvaluator

java.lang.Object
  net.sf.saxon.sxpath.XPathEvaluator

public class XPathEvaluator

extends java.lang.Object

This is a cut-down version of the XPathEvaluator in the net.sf.saxon.xpath package. It provides much of the same functionality, but without any dependencies on the JAXP 1.3 interfaces, which are not available in JDK 1.4. The main restrictions are that it does not support mechanisms for defining variables or functions.

Constructor Summary

XPathEvaluator()
Default constructor.

XPathEvaluator(Configuration config)
Construct an XPathEvaluator with a specified configuration.

Method Summary

NodeInfo	build(javax.xml.transform.Source source) Build a source document.
XPathExpression	createExpression(java.lang.String expression) Prepare an XPath expression for subsequent evaluation.
Configuration	getConfiguration() Get the Configuration in use
NamespaceResolver	getNamespaceResolver() Get the external namespace resolver, if one has been set using setNamespaceResolver(net.sf.saxon.om.NamespaceResolver)
IndependentContext	getStaticContext() Get the current static context.
static void	main(java.lang.String[] args) A simple command-line interface for the XPathEvaluator (not documented).
void	setNamespaceResolver(NamespaceResolver namespaceContext) Set the external namespace resolver to be used.
void	setStaticContext(IndependentContext context) Set the static context for compiling XPath expressions.
void	setStripSpace(boolean strip) Indicate whether all whitespace text nodes in the source document are to be removed.

Methods inherited from class java.lang.Object

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

Constructor Detail

XPathEvaluator

public XPathEvaluator()

Default constructor. Creates an XPathEvaluator with a default configuration and name pool.

XPathEvaluator

public XPathEvaluator(Configuration config)

Construct an XPathEvaluator with a specified configuration.

Parameters:

config - the configuration to be used

Method Detail

getConfiguration

public Configuration getConfiguration()

Get the Configuration in use

setStripSpace

public void setStripSpace(boolean strip)

Indicate whether all whitespace text nodes in the source document are to be removed.

Parameters:

strip - True if all whitespace text nodes are to be stripped from the source document, false otherwise. The default if the method is not called is false.

build

public NodeInfo build(javax.xml.transform.Source source)
               throws XPathException

Build a source document.

Parameters:

source - a JAXP Source object. This may be any implementation of Source that Saxon recognizes: not only the standard kinds of source such as StreamSource, SAXSource, and DOMSource, but also for example a JDOM or XOM DocumentWrapper.

Returns:

the NodeInfo representing the root of the constructed tree.

Throws:

XPathException - if, for example, XML parsing fails.

setStaticContext

public void setStaticContext(IndependentContext context)

Set the static context for compiling XPath expressions. This provides control over the environment in which the expression is compiled, for example it allows namespace prefixes to be declared, variables to be bound and functions to be defined. For most purposes, the static context can be defined by providing and tailoring an instance of the IndependentContext class. Until this method is called, a default static context is used, in which no namespaces are defined other than the standard ones (xml, xslt, and saxon), and no variables or functions (other than the core XPath functions) are available.

getStaticContext

public IndependentContext getStaticContext()

Get the current static context. This will always return a value; if no static context has been supplied by the user, the system creates its own.

createExpression

public XPathExpression createExpression(java.lang.String expression)
                                 throws XPathException

Prepare an XPath expression for subsequent evaluation.

Parameters:

expression - The XPath expression to be evaluated, supplied as a string.

Returns:

an XPathExpression object representing the prepared expression

Throws:

XPathException - if the syntax of the expression is wrong, or if it references namespaces, variables, or functions that have not been declared.

setNamespaceResolver

public void setNamespaceResolver(NamespaceResolver namespaceContext)

Set the external namespace resolver to be used. This overrides any namespaces declared directly using declareNamespace on the staticContext object

Parameters:

namespaceContext - The namespace context

getNamespaceResolver

public NamespaceResolver getNamespaceResolver()

Get the external namespace resolver, if one has been set using setNamespaceResolver(net.sf.saxon.om.NamespaceResolver)

Returns:

the namespace context if set, or null otherwise

main

public static void main(java.lang.String[] args)
                 throws java.lang.Exception

A simple command-line interface for the XPathEvaluator (not documented). First parameter is the filename containing the source document, second parameter is the XPath expression.

Throws:

java.lang.Exception