scala(8)Actor

Actor 用于并行计算 ，Actor之间可以进行消息发送。
case class 是理想的载体，Actor的优势在于不基于资源与锁的基础上，完成并发。
Actor的建立

import scala.actors._class ActorOps {}object helloActor extends Actor{  def act(): Unit ={    for (i<-1 to 5){      println("the is a scala actor")      Thread.sleep(2000)    }  }}object ActorOps{  def main(args: Array[String]) {    helloActor.start()  }}

不常用的Actor创建
import scala.actors.Actor._
val secondActor=actor{
for (i<-1 to 5){
println(“the is a second scala actor”)
Thread.sleep(2000)
}

Actor的消息机制
!单方面传输
!?必须等到另一个Actor完成
!!取得发过去消息的结果

import scala.actors._class ActorOps {}object helloActor extends Actor{  def act(): Unit ={    while (true){      receive{        case x:Int => println("got an Int")        case _=>println("some other type")      }    }  }}object ActorOps{  def main(args: Array[String]) {    helloActor.start()    helloActor ! "hi,the is scala!"    helloActor ! 1  }

Actor共享线程
通过react来进行线程共享

import scala.actors._object NameResolver extends Actor{  import java.net.{InetAddress,UnknownHostException}  def act() {    react {      case Net(name: String, actor: Actor) => actor ! getIP(name)//actor处可以改成sender表示发送的那个actor 用于回复发来的Actor      case "EXIT" => println("exiting")      case msg =>        println("Unhandled message:" + msg)        act()    }  }    def getIP(name:String): Option[InetAddress] ={      try{        Some(InetAddress.getByName(name))      }catch {        case _:UnknownHostException=>None      }    }}object ActorOps {  def main(args: Array[String]) {      NameResolver.start      NameResolver ! ("www.baidu.com",self)//self代表当前actor，所以下面的self.receive能接收到信息      println(self.receiveWithin(1000){case x=>x})  }}

多个Actor协同工作

下面程序NameResolve把处理好的数据发给helloActor 。
好的actor使用case class来完成传递消息，结束时使用匹配模式。

import scala.actors._import scala.actors.Actor._class ActorOps {}object NameResolver extends Actor{  import java.net.{InetAddress,UnknownHostException}  def act() {    react {      case (name: String, actor: Actor) => actor ! getIP(name)//接受一个元组并把消息传给actor//      case Net(name: String, actor: Actor) => actor ! getIP(name)//使用case class传递数据      case "EXIT" => println("exiting")      case msg =>        println("Unhandled message:" + msg)        act()    }  }    def getIP(name:String): Option[InetAddress] ={      try{        Some(InetAddress.getByName(name))      }catch {        case _:UnknownHostException=>None      }    }}object helloActor extends Actor{  def act(): Unit ={    while (true){      receive{       case msg=> print("receive massage:"+msg)        case x:Int => println("got an Int")        case _=>println("some other type")      }    }  }}case class Net(name: String, actor: Actor)//case classobject ActorOps {  def main(args: Array[String]) {      NameResolver.start      NameResolver ! ("www.baidu.com",helloActor)//发送要解析的网址，发给的actor//      NameResolver ! Net("www.baidu.com",helloActor)      helloActor.start()  }}