anchor.diff:  = groovy_event
  -:author: 
  -:revnumber: 
  +:author:
  +:revnumber:
   :revdate: 2016/03/17 20:48
   :relfileprefix: ../../
   :imagesdir: ../..
  
positive.code: }
  
  class CustomEvent{
      
  }
  handler = new EventHandler();
  eventBus.register(handler);
  
negative.code: 
  === Trigger
  
  If you build up your game world's activites from Action, Trigger is the brick to build Gameplay. It's the combination of : Event + Condition → Action
  
  The concept of trigger can be describle like this: When an Event happen, if it's passed a Condition check, the Action is taken. A more detailed description envolve: the Enviroment - a specific Context of those 3 (E - C - A), Durations , Threaded or not, Executor … But here we concern the most simple form, the Context is the single specific that procedure the Event and its Global awareness.
  
  In Groovy,
  
  *  Event is Class based, mentioned in the chapter above.
  *  Condition can be modeled with a Closure
  *  Action also very suitable with a Closure representation.
  
  
  ==== Example1:
  
  [source,java]
  ----
  