org.mmbase.util.functions
Class BeanFunction

java.lang.Object
  org.mmbase.util.functions.AbstractFunction
      org.mmbase.util.functions.BeanFunction

All Implemented Interfaces:

Comparable, Function, Serializable

public class BeanFunction

extends AbstractFunction

One or more functions based on a Java-bean. Every setter method of the bean corresponds with one parameter. The default value of the parameter can be defined with the getter method (which will be called immediately after instantiation of such a Class). All other methods (with no arguments) of the class correspond to the functions. So, you can implement more bean-functions in the same class, as long as they have the same parameters. A BeanFunction can be aquired via FunctionFactory.getFunction(Class, String) (which delegates to a static method in this class).

Since:

MMBase-1.8

Version:

$Id: BeanFunction.java,v 1.8 2005/12/08 16:18:21 michiel Exp $

Author:

Michiel Meeuwissen

See Also:

MethodFunction, FunctionFactory, Serialized Form

Field Summary

Fields inherited from class org.mmbase.util.functions.AbstractFunction

name, returnType

Method Summary

static Class	getClass(Class claz, String name) Utility function, searches an inner class of a given class.
static Function	getFunction(Class claz, String name) Gives back a Function object based on the 'bean' concept.
Object	getFunctionValue(Parameters parameters) Executes the defined function supplying the given arguments. Instantiates the bean, calls all setters using the parameters, and executes the method associated with this function.

Methods inherited from class org.mmbase.util.functions.AbstractFunction

compareTo, createParameters, equals, getDescription, getFunctionValueWithList, getName, getParameterDefinition, getReturnType, hashCode, setDescription, setParameterDefinition, setReturnType, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Method Detail

getClass

public static Class getClass(Class claz,
                             String name)

Utility function, searches an inner class of a given class. This inner class can perhaps be used as a bean. Used in JSP/taglib.

Parameters:

claz - The class to be considered

name - The name of the inner class

Throws:

IllegalArgumentException - if claz has no inner class with that name

getFunction

public static Function getFunction(Class claz,
                                   String name)
                            throws IllegalAccessException,
                                   InstantiationException,
                                   InvocationTargetException

Gives back a Function object based on the 'bean' concept. Called from FunctionFactory

Throws:

IllegalAccessException

InstantiationException

InvocationTargetException

getFunctionValue

public Object getFunctionValue(Parameters parameters)

Executes the defined function supplying the given arguments. Instantiates the bean, calls all setters using the parameters, and executes the method associated with this function.

Specified by:

getFunctionValue in interface Function

Specified by:

getFunctionValue in class AbstractFunction

Parameters:

parameters - The parameters for the function. To specify an empty parameter list use Parameters.VOID. Implementors are encouraged to support null too.

Returns:

The function value, which can be of any type compatible to AbstractFunction.getReturnType()

See Also:

AbstractFunction.createParameters()