Package org.apache.commons.jxpath

Class ClassFunctions

java.lang.Object

org.apache.commons.jxpath.ClassFunctions

All Implemented Interfaces:

Functions

public class ClassFunctions
extends Object
implements Functions

Extension functions provided by a Java class. Let's say we declared a ClassFunction like this:

 new ClassFunctions(Integer.class, "int")
 

We can now use XPaths like:

"int:new(3)"

Equivalent to Integer.valueOf(3)

"int:getInteger('foo')"

Equivalent to Integer.getInteger("foo")

"int:floatValue(int:new(4))"

Equivalent to Integer.valueOf(4).floatValue()

If the first argument of a method is ExpressionContext, the expression context in which the function is evaluated is passed to the method.

Constructor Summary

Constructors

Constructor	Description
ClassFunctions(Class functionClass, String namespace)	Constructs a new ClassFunctions.

Method Summary

Modifier and Type	Method	Description
Function	getFunction(String namespace, String name, Object[] parameters)	Returns a Function, if any, for the specified namespace, name and parameter types.
Set<String>	getUsedNamespaces()	Returns a set of one namespace - the one specified in the constructor.

Methods inherited from class java.lang.Object

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

Constructor Details

ClassFunctions

public ClassFunctions(Class functionClass,
 String namespace)

Constructs a new ClassFunctions.

Parameters:

functionClass - Class providing the functions

namespace - assigned ns

Method Details

getFunction

public Function getFunction(String namespace,
 String name,
 Object[] parameters)

Returns a Function, if any, for the specified namespace, name and parameter types.

Specified by:

getFunction in interface Functions

Parameters:

namespace - if it is not the namespace specified in the constructor, the method returns null

name - is a function name or "new" for a constructor.

parameters - Object[] of parameters

Returns:

a MethodFunction, a ConstructorFunction or null if there is no such function.

getUsedNamespaces

public Set<String> getUsedNamespaces()

Returns a set of one namespace - the one specified in the constructor.

Specified by:

getUsedNamespaces in interface Functions

Returns:

a singleton