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: 1.9 $ $Date: 2004/02/29 14:17:42 $

Author:

Dmitri Plotnikov

Field Summary

private static java.lang.Object[]	EMPTY_ARRAY
private java.lang.Class	functionClass
private java.lang.String	namespace

Constructor Summary

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

Method Summary

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

functionClass

private java.lang.Class functionClass

namespace

private java.lang.String namespace

EMPTY_ARRAY

private static final java.lang.Object[] EMPTY_ARRAY

Constructor Detail

ClassFunctions

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

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

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.

Returns:

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