Java 程序员必备scala基础语法

class SendResponse(request: Request,
                     val responseSend: Send,
                     val responseAsString: Option[String],
                     val onCompleteCallback: Option[Send => Unit]) 
  extends Response(request) {
    ......
    // 指定输入参数onCompleteCallback
    override def onComplete: Option[Send => Unit] = onCompleteCallback
}