/**
  * The singleton method
  *
  * @return TransitionFactory
  */
 public static function instance()
 {
     if (!isset(self::$_instance)) {
         $c = __CLASS__;
         self::$_instance = new $c(Workflow_Transition_ConditionFactory::build());
     }
     return self::$_instance;
 }
 /**
  * The singleton method
  * 
  * @return TransitionFactory
  */
 public static function instance()
 {
     if (!isset(self::$_instance)) {
         $c = __CLASS__;
         self::$_instance = new $c();
     }
     return self::$_instance;
 }