public UndoEvent(UndoActionInterface parentObj,FieldIdEnum fieldId,Object oldValue,Object newValue){
  this.parentObj=parentObj;
  this.fieldId=fieldId;
  this.oldValue=oldValue;
  this.newValue=newValue;
  representation=String.format("Storing value : %s Old : %s New : %s",fieldId.toString(),oldValue,newValue);
}

public UndoEvent ( UndoActionInterface parentObj , FieldIdEnum fieldId , Object oldValue , Object newValue ) { this . parentObj = parentObj ; this . fieldId = fieldId ; this . oldValue = oldValue ; this . newValue = newValue ; representation = String . format ( "Storing value : %s Old : %s New : %s" , fieldId . toString ( ) , oldValue , newValue ) ; }
instantiates a new undo event .
