org.jaxen
Interface FunctionContext

All Known Implementing Classes:
SimpleFunctionContext, XPathFunctionContext

public interface FunctionContext

Implemented by classes that know how to resolve XPath function names and namespaces to implementations of these functions.

By using a custom FunctionContext, new or different functions may be installed and available to XPath expression writers.

Author:
bob mcwhirter
See Also:
XPathFunctionContext

Method Summary
 Function getFunction(String namespaceURI, String prefix, String localName)
          An implementation should return a Function implementation object based on the namespace URI and local name of the function-call expression.
 

Method Detail

getFunction

Function getFunction(String namespaceURI,
                     String prefix,
                     String localName)
                     throws UnresolvableException
An implementation should return a Function implementation object based on the namespace URI and local name of the function-call expression.

It must not use the prefix parameter to select an implementation, because a prefix could be bound to any namespace; the prefix parameter could be used in debugging output or other generated information. The prefix may otherwise be completely ignored.

Parameters:
namespaceURI - the namespace URI to which the prefix parameter is bound in the XPath expression. If the function call expression had no prefix, the namespace URI is null.
prefix - the prefix that was used in the function call expression
localName - the local name of the function-call expression. If there is no prefix, then this is the whole name of the function.
Returns:
a Function implementation object.
Throws:
UnresolvableException - when the function cannot be resolved


Copyright © 2001-2008 Codehaus. All Rights Reserved.