您可以刷新或重新显示未刷新的远程登录输入吗?

Question

我正在编写一个基于文本的老式telnet服务器，现在它是Scala中一个美化的聊天室，带有基于Akkaactor的IO。正在发生的事情是客户端客户端将开始键入某些内容，然后会发生一个事件，当它被写入时，它会清除任何已经键入的内容。 在下面的示例中，Tom 开始键入"say are you？"，但 Fred 在只键入"say How ar"并且此输入被清除后到达：

Tom > say How ar
Fred has arrived.
Tom > 

有没有办法让telnet重新显示它尚未刷新的输出缓冲区？

这是服务器：

class TcpServer(port: Int) extends Actor {
  import TcpServer._
  import context.system
  val log = Logging(system, this)
  var connectionNum: Int = 1
  log.info(STARTING_SERVER)
  IO(Tcp) ! Bind(self, new InetSocketAddress("0.0.0.0", port))
  def receive = {
    case b @ Bound(localAddress) =>
      log.info(PORT_BOUND, localAddress)
    case c @ Connected(remote, local) =>
      log.info(CONNECTION_ACCEPTED)
      context.actorOf(ConnectionHandler.connectionProps(sender()), s"conn$connectionNum")
      connectionNum += 1
    case CommandFailed(_: Bind) =>
      log.error(BINDING_FAILED)
      context stop self
  }
}

下面是 ConnectionHandler，它是配套对象，以及它使用的消息案例类：

class ConnectionHandler(connection: ActorRef) extends Actor {
  import context._
  val log = Logging(context.system, this)
  connection ! Register(self)
  var delegate = actorOf(Props[LoginHandler], "login")
  watch(delegate)
  def receive = {
    case Received(data) =>
      val dataString = data.utf8String.trim
      log.info("Received data from connection: {}", dataString)
      delegate ! Input(dataString)
    case Output(content) =>
      connection ! Write(ByteString(content))
    case LoggedIn(user) =>
      unwatch(delegate)
      delegate ! PoisonPill
      delegate = actorOf(UserHandler.connectionProps(user), user.name.toLowerCase)
      watch(delegate)
    case Terminated =>
      log.warning("User delegate died unexpectedly.")
      connection ! ConfirmedClose
    case CloseConnection(message) =>
      connection ! Write(ByteString(message + "n"))
      connection ! ConfirmedClose
      log.info("User quit.")
    case ConfirmedClosed =>
      log.info("Connection closed.")
      stop(self)
    case PeerClosed =>
      log.info("Connection closed by client.")
      stop(self)
  }
}
object ConnectionHandler {
  def connectionProps(connection: ActorRef): Props = Props(new ConnectionHandler(connection))
}
case class Input(input: String)
case class Output(output: String)
case class LoggedIn(user: User)
case class CloseConnection(message: String)

Answer 1

好的，在最终正确措辞我的谷歌查询之后，我在这里找到了我需要的东西：强制远程登录客户端进入字符模式

基本的解决方案是，我强制客户端在时间模式下进入角色，并回显我关心的角色。 这样做的好处是，现在我可以执行选项卡完成，命令历史记录并使密码不显示。

以下是相关的代码片段：

val controlString = ByteString('u00ff','u00fb','u0001','u00ff','u00fb','u0003','u00ff','u00fc','u0022')
connection ! Write(controlString)