OOPStyle scala

OOPStyle.scala

object MyApp extends App {
  val dao = createDaoImpl()
  val eventBus = createEventBus()

  BusinessLogic(dao, eventBus).foo(123)
}

trait Dao {
  def findById(id: Long): String
}

trait EventBus {
  def publish(message: String)
}

class BusinessLogic(dao: Dao, eventBus: EventBus) {
  def foo(entityId: Long) = {
    val entity = dao.findById(entityId)
    eventBus.publish(entity)
  }
}

object BusinessLogic {
  def apply(dao: Dao, eventBus: EventBus): BusinessLogic = new BusinessLogic(dao, eventBus)
}