org.apache.commons.jxpath

Class ClassFunctions

java.lang.Object

org.apache.commons.jxpath.ClassFunctions

All Implemented Interfaces:

Functions

public class ClassFunctions
extends java.lang.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 new Integer(3)

"int:getInteger('foo')"

Equivalent to Integer.getInteger("foo")

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

Equivalent to new Integer(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.

Version:

$Revision: 652845 $ $Date: 2008-05-02 12:46:46 -0500 (Fri, 02 May 2008) $

Field Summary

Fields

Modifier and Type	Field and Description
private static java.lang.Object[]	EMPTY_ARRAY
private java.lang.Class	functionClass
private java.lang.String	namespace

Constructor Summary

Constructors

Constructor and Description
ClassFunctions(java.lang.Class functionClass, java.lang.String namespace) Create a new ClassFunctions.

Method Summary

Modifier and Type	Method and Description
Function	getFunction(java.lang.String namespace, java.lang.String name, java.lang.Object[] parameters) Returns a Function, if any, for the specified namespace, name and parameter types.
java.util.Set	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

Field Detail

EMPTY_ARRAY

private static final java.lang.Object[] EMPTY_ARRAY

functionClass

private java.lang.Class functionClass

namespace

private java.lang.String namespace

Constructor Detail

ClassFunctions

public ClassFunctions(java.lang.Class functionClass,
                      java.lang.String namespace)

Create a new ClassFunctions.

Parameters:

functionClass - Class providing the functions

namespace - assigned ns

Method Detail

getUsedNamespaces

public java.util.Set getUsedNamespaces()

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

Specified by:

getUsedNamespaces in interface Functions

Returns:

a singleton

getFunction

public Function getFunction(java.lang.String namespace,
                            java.lang.String name,
                            java.lang.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.