Package com.werken.xpath

Class XPathFunctionContext

java.lang.Object

com.werken.xpath.XPathFunctionContext

All Implemented Interfaces:

FunctionContext

public class XPathFunctionContext
extends java.lang.Object
implements FunctionContext

Implementation of FunctionContext which matches the core function library as described by the W3C XPath Specification.

May be directly instantiated or subclassed. A Singleton is provided for ease-of-use in the default case of bare XPaths.

Author:

bob mcwhirter (bob @ werken.com)

Constructor Summary

Constructors

Constructor	Description
XPathFunctionContext()

Method Summary

Modifier and Type	Method	Description
protected void	addFunction(java.lang.String name, Function func)	Add a function to this FunctionContext
Function	getFunction(java.lang.String name)	Retrieve a named function
static XPathFunctionContext	getInstance()	Get the XPathFunctionContext singleton.

Methods inherited from class java.lang.Object

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

Constructor Detail

XPathFunctionContext

public XPathFunctionContext()

Method Detail

getInstance

public static XPathFunctionContext getInstance()

Get the XPathFunctionContext singleton.

Returns:

The global, immutable FunctionContext which matches the functions as described by the W3C XPath specification.

addFunction

protected void addFunction(java.lang.String name,
                           Function func)

Add a function to this FunctionContext

Parameters:

name - The name of the function.

func - The implementing Function Object.

getFunction

public Function getFunction(java.lang.String name)

Retrieve a named function

Retrieve the named function object, or null if no such function exists.

Specified by:

getFunction in interface FunctionContext

Parameters:

name - The name of the function sought.

Returns:

The Function matching the specified name.

See Also:

com.werken.xpath.ContextHelper#setFunctionContext