为什么AtmosphereClient无法连接到服务器？

Question

我正在使用Scalatra Atmosphere的websocket，如下所示：

package com.sweetsoft.app

import org.scalatra._
import org.json4s.JsonDSL._
import org.json4s._
import org.scalatra._
import org.scalatra.atmosphere._
import org.scalatra.json.{JValueResult, JacksonJsonSupport}
import org.scalatra.scalate.ScalateSupport

import scala.concurrent.ExecutionContext.Implicits.global
import java.util.Date



class SapBroker extends ScalatraServlet
  with ScalateSupport with JValueResult
  with JacksonJsonSupport with SessionSupport
  with AtmosphereSupport {

  implicit protected val jsonFormats: Formats = DefaultFormats

  get("/") {
      contentType="text/html"
  }

  atmosphere("/broker") {
    new AtmosphereClient {
      def receive: AtmoReceive = {
        case Connected =>
          println("Client %s is connected" format uuid)
          broadcast(("author" -> "Someone") ~ ("message" -> "joined the room") ~ ("time" -> (new Date().getTime.toString )), Everyone)

        case Disconnected(ClientDisconnected, _) =>
          println("Client %s is connected" format uuid)

        case Disconnected(ServerDisconnected, _) =>
          println("Server disconnected the client %s" format uuid)

        case JsonMessage(json) =>
          println("Server disconnected the client %s" format uuid)
      }
    }
  }

  error {
    case t: Throwable => t.printStackTrace()
  }

}  

服务器运行无任何错误，但是我尝试使用websocket客户端连接服务器，如下所示：

如您所见，它无法连接到服务器。但是在控制台上，它显示：

2019-03-15 21:24:25.466:INFO:oejsh.ContextHandler:main: Started o.e.j.w.WebAppContext@1c53fd30{/,file:///home/developer/scala/sapbroker/target/webapp/,AVAILABLE}{file:///home/developer/scala/sapbroker/target/webapp/}
2019-03-15 21:24:25.474:INFO:oejs.AbstractConnector:main: Started ServerConnector@5dda6f9{HTTP/1.1,[http/1.1]}{0.0.0.0:8080}
2019-03-15 21:24:25.475:INFO:oejs.Server:main: Started @1611ms
21:24:25.698 [Thread-16] INFO  o.atmosphere.cpr.AtmosphereFramework - Latest version of Atmosphere's JavaScript Client 2.3.8
21:24:25.698 [Thread-16] INFO  o.atmosphere.cpr.AtmosphereFramework - 

        Atmosphere Framework Updates:
        Major Update available (new features): 2.5.2
Client 67262482-3527-4522-babf-e9b3f932eb14 is connected
Client 67262482-3527-4522-babf-e9b3f932eb14 is connected 

客户端已连接，但是Smart Websocket客户端说，它无法连接到服务器。 怎么了？