code: public void attachItinerary(final Itinerary itinerary) {
  		Validate.notNull(itinerary);
  
  		// Decouple the old itinerary from this cargo
  		itinerary().setCargo(null);
  		// Couple this cargo and the new itinerary
  		setItinerary(itinerary);
  		itinerary().setCargo(this);
  	}
docs: Attach a new itinerary to this cargo.
  
  @param itinerary
  an itinerary. May not be null.