用scala語言，開發好了在spark平臺上可以一直執行的機器學習模型
現在有個需求：
要遠端呼叫該模型的一些方法並獲取結果
那麼可以使用jetty在伺服器端主節點佔用一個埠然後對外提供http服務

package com.xxx.rec.basic.ccam.jetty

import javax.servlet.http.{HttpServletRequest, HttpServletResponse}
import com.xxx.rec.basic.ccam.CanonicalCorrelationAnalysisModel
import org.mortbay.jetty.{HttpStatus, Request, Server}
import org.mortbay
 
.jetty.handler._


object CannonicalCorrelationAnalysisModelJerseyServer
  extends AbstractHandler{

  var model: CanonicalCorrelationAnalysisModel = null

  /**
    * 處理請求 返回響應
    * @param target
    * @param request
    * @param response
    * @param dispatch
    */
  override def handle(target: String,
                      request: HttpServletRequest,
                      response: HttpServletResponse,
                      dispatch: Int): Unit = {
    val url=request.getRequestURI
 

    url.substring(url.lastIndexOf("/")+1,url.length) match {
      case "recommend" => {
        //request中的target 用,號分割
        val target: Seq[String] = request.getParameter("target").split(",").toSeq
        val topNum: Int = request.getParameter("topNum").toInt
        val result = model.recommend
 
(target, topNum)
        response.setStatus(HttpStatus.ORDINAL_200_OK);
        response.getWriter().println(result.mkString(","))
        request.asInstanceOf[Request].setHandled(true)
        response.getWriter.close()
      }
      case _ => {
        response.setStatus(HttpStatus.ORDINAL_404_Not_Found);
        request.asInstanceOf[Request].setHandled(true)
      }
    }
  }

  def main(args: Array[String]): Unit = {
    import org.apache.spark.{SparkConf, SparkContext}
    val sparkConf = new SparkConf().setAppName("CanonicalCorrelationAnalysisModelDemo")
    val textFilePath = "file:///home/xxx/xxx.txt"
    val sc = new SparkContext(sparkConf)
    val data = sc.textFile(textFilePath).map { line =>
      line.split(' ')
    }.cache()

    model = CanonicalCorrelationAnalysisModel.createModel(data, 0.3, 5)

    val server=new Server(9998)
    server.setHandler(this)
    server.start()

  }

}

該程式執行後佔用了伺服器端主節點的9998埠，通過http訪問即可