UseCaseExecutor.scala

abstract class UseCaseExecutor {
  
  def execute[T](useCase: UseCase[T]): Try[T] = {

    Try {
      useCase.validate().foreach { error => throw error }
      val result = useCase.execute()
      useCase.journal.foreach(appendJournal)
      result
    }

  }

  def appendJournal(journal: Journal): Unit
}