使用scala实现wordcount的简单计数

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package wordCountimport scala.actors.{Actor, Future}import scala.collection.mutable.ListBufferimport scala.io.Source/**  * Created by Adminstrator on 2017/6/10.  */class MyActorWC extends Actor{  override def act(): Unit = {    loop {      react {        case WordCount(filePath) => {          val strList: List[String] = Source.fromFile(filePath).getLines().toList          val values: Map[String, Int] = strList.flatMap(_.split(" ")).map((_, 1)).groupBy(_._1).mapValues(_.size)//          sender ! SendResult(values)          sender ! values        }        case StopProcess() => {          exit()        }      }    }  }}case class WordCount(var filePath : String)case class StopProcess()case class SendResult(var result : Map[String,Int])object MyWordCount extends  App{//  val re = ListBuffer[Future[Any]]()//  val resultMap = ListBuffer[Map[String,Int]]()  val re = new ListBuffer[Future[Any]]  val resultMap = new ListBuffer[Map[String,Int]]  val path = Array("E:\\大数据（临时存放目录）\\测试数据\\a.txt","E:\\大数据（临时存放目录）\\测试数据\\b.txt","E:\\大数据（临时存放目录）\\测试数据\\c.txt")  for (i <- path){    val m = new MyActorWC    m.start()    val future: Future[Any] = m !! WordCount(i)    re += future  }  while (re.size>0){    val futures: ListBuffer[Future[Any]] = re.filter(_.isSet)    for(j <- futures){      val reMap: Map[String, Int] = j.apply().asInstanceOf[Map[String,Int]]      resultMap += reMap      re -= j    }    Thread.sleep(1000)  }  println("计数结果---》》"+resultMap.flatten.groupBy(_._1).mapValues(_.foldLeft(0)(_+_._2)))}

注意的地方：一：val表示值不可变或者引用不可变，如果是List或者Map，它们的元素是可以改变的。

    二：val re = ListBuffer[Future[Any]]()引入的是不可变的List，同理Map也一样，如果使用可变的需要new

    三：j.apply().asInstanceOf[Map[String,Int]]注意异步发送消息返回的类型是否一致，

  如果返回对象不能使用map接收

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