decoupled configuration code structure

Application.scala

object Application{
  def run(config: Config): Unit = {
    val db = connectToDb( config.dbHost, config.dbPort )
    ...
  }
}
case class Config(
  dbHost: String,
  port: Int
)

ProductionConfig.scala

object ProductionConfig{
  def main(args: Array[String]): Unit = {
    Application.run( Config("db.production-server.com",12345) )
  }
}

TestConfig.scala

object TestConfig{
  def main(args: Array[String]): Unit = {
    Application.run( Config("db.test-server.com",10000) )
  }
}