org.xmlpull.v1.builder.xpath.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.

See Also:

XPathFunctionContext

Method Summary

Function

getFunction(java.lang.String namespaceURI, java.lang.String prefix, java.lang.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(java.lang.String namespaceURI,
                     java.lang.String prefix,
                     java.lang.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.