Scala编程实战_scala实战

package cn.akkaTest.spark
 
  import scala.concurrent.duration._
 
  import akka.actor.{Props, ActorSystem, Actor}
 
  import akka.actor.Actor.Receive
 
  import com.typesafe.config.ConfigFactory
  import scala.collection.mutable
 
  
  /**
 
  * Master为整个集群中的主节点
 
  * Master继承了Actor
 
  */
 
  class Master extends Actor{
 
 
  //保存WorkerID和Work信息的map
 
  val idToWorker = new mutable.HashMap[String, WorkerInfo]
 
  //保存所有Worker信息的Set
 
  val workers = new mutable.HashSet[WorkerInfo]
 
  //Worker超时时间
 
  val WORKER_TIMEOUT = 10 * 1000
 
  //重新receive方法
  
  //导入隐式转换，用于启动定时器
 
  import context.dispatcher
 
    //构造方法执行完执行一次
 
  override def preStart(): Unit = {
 
    //启动定时器，定时执行
 
    context.system.scheduler.schedule(0 millis, WORKER_TIMEOUT millis, self, CheckOfTimeOutWorker)
 
  }
 
 
  //该方法会被反复执行，用于接收消息，通过case class模式匹配接收消息
 
  override def receive: Receive = {
 
    //Worker向Master发送的注册消息
 
    case RegisterWorker(id, workerHost, memory, cores) => {
 
      if(!idToWorker.contains(id)) {
 
        val worker = new WorkerInfo(id, workerHost, memory, cores)
 
        workers.add(worker)
 
        idToWorker(id) = worker
 
        sender ! RegisteredWorker("192.168.10.1")
 
      }
 
    }
 
      //Worker向Master发送的心跳消息
 
    case HeartBeat(workerId) => {
 
      val workerInfo = idToWorker(workerId)
 
      workerInfo.lastHeartbeat = System.currentTimeMillis()
 
    }
 
    //Master自己向自己发送的定期检查超时Worker的消息
 
    case CheckOfTimeOutWorker => {
 
      val currentTime = System.currentTimeMillis()
 
      val toRemove = workers.filter(w => currentTime - w.lastHeartbeat > WORKER_TIMEOUT).toArray
 
      for(worker <- toRemove){
 
        workers -= worker
 
        idToWorker.remove(worker.id)
 
      }
 
      println("worker size: " + workers.size)
 
    }
 
  }
 
}
 
  
  object Master {
 
  //程序执行入口
 
  def main(args: Array[String]) {
 
  
 
    val host = "192.168.10.1"
 
    val port = 8888
 
    //创建ActorSystem的必要参数
 
    val configStr =
 
      s"""
 
         |akka.actor.provider = "akka.remote.RemoteActorRefProvider"
 
         |akka.remote.netty.tcp.hostname = "$host"
 
         |akka.remote.netty.tcp.port = "$port"
 
       """.stripMargin
 
    val config = ConfigFactory.parseString(configStr)
 
    //ActorSystem是单例的，用来创建Actor
 
    val actorSystem = ActorSystem.create("MasterActorSystem", config)
 
    //启动Actor，Master会被实例化，生命周期方法会被调用
 
    actorSystem.actorOf(Props[Master], "Master")
 
  }
 
}

package cn.akkaTest.spark
 
 
  import java.util.UUID
 
  import scala.concurrent.duration._
 
  import akka.actor.{ActorSelection, Props, ActorSystem, Actor}
 
  import akka.actor.Actor.Receive
 
  import com.typesafe.config.ConfigFactory
 
 
  /**
 
  * Worker为整个集群的从节点
 
  * Worker继承了Actor
 
  */
 
  class Worker extends Actor{
 
  
  //Worker端持有Master端的引用（代理对象）
 
  var master: ActorSelection = null
 
  //生成一个UUID，作为Worker的标识
 
  val id = UUID.randomUUID().toString
 
 
  //构造方法执行完执行一次
 
  override def preStart(): Unit = {
 
    //Worker向MasterActorSystem发送建立连接请求
 
    master = context.system.actorSelection("akka.tcp://MasterActorSystem@192.168.10.1:8888/user/Master")
 
    //Worker向Master发送注册消息
 
    master ! RegisterWorker(id, "192.168.10.1", 10240, 8)
 
  }
 
  
 
  //该方法会被反复执行，用于接收消息，通过case class模式匹配接收消息
 
  override def receive: Receive = {
 
    //Master向Worker的反馈信息
 
    case RegisteredWorker(masterUrl) => {
 
      import context.dispatcher
 
      //启动定时任务，向Master发送心跳
 
      context.system.scheduler.schedule(0 millis, 5000 millis, self, SendHeartBeat)
 
    }
 
  
 
    case SendHeartBeat => {
 
      println("worker send heartbeat")
 
      master ! HeartBeat(id)
 
    }
 
  }
 
}
 
  
 
  object Worker {
 
  def main(args: Array[String]) {
 
    val clientPort = 2552
 
    //创建WorkerActorSystem的必要参数
 
    val configStr =
 
      s"""
 
         |akka.actor.provider = "akka.remote.RemoteActorRefProvider"
 
         |akka.remote.netty.tcp.port = $clientPort
 
       """.stripMargin
 
    val config = ConfigFactory.parseString(configStr)
 
    val actorSystem = ActorSystem("WorkerActorSystem", config)
 
    //启动Actor，Master会被实例化，生命周期方法会被调用
 
    actorSystem.actorOf(Props[Worker], "Worker")
 
  }
 
}