robotlegs 1. Being able to access this API (SERVICE) directly can save your application from unnecessary command classes to achieve the same goal. — Типа инжектим Service в Mediator, и экономим на Command классах. 2.If the service API is repeatedly accessed in the same way from many mediators, it can be beneficial to encapsulate this behavior in a command to keep the behavior consistent and reduce the repetition of injecting the service and accessing it directly in your mediators. — Если Service нужен одинаково в нескольких медиаторах, то удобнее использовать для уведомления Servica класс Command. — Я предпочитаю второй путь, хоть и оба варианта дружат с decoupling.