org.perfectjpattern.core.api.behavioral.observer.data
Class NullEventData

java.lang.Object
  org.perfectjpattern.core.api.behavioral.observer.data.NullEventData

All Implemented Interfaces:

IEventData, ISingleton

public final class NullEventData
extends Object
implements IEventData, ISingleton

Null Object Pattern implementation of IEventData. Prevents different ISubject implementations from pushing null into the IObserver's update method.

NullEventData is a Singleton therefore it can not be directly instantiated, neither it may be extended.

Version:

$Revision: 1.0 $ $Date: Jun 19, 2007 10:17:38 PM $

Author:

Giovanni Azua

Method Summary

static NullEventData

getInstance() Returns Singleton instance of NullEventData.

Methods inherited from class java.lang.Object

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

Method Detail

getInstance

public static NullEventData getInstance()

Returns Singleton instance of NullEventData.

Returns:

Singleton instance of NullEventData.