Scala AOP

trait Action { 

  def doAction
}
trait TBeforeAfter extends Action {
  abstract override def doAction {
    println("Initialization")
    super.doAction
    println("Destroyed")
  }
}

class Work extends Action{
  override def doAction = println("Working...")
}

object UseTrait extends App{
  val work = new Work with TBeforeAfter
  work.doAction
}

输出:

Initialization
Working...
Destroyed

解释:

work.doAction会调用TBeforeAfter的doAction方法,所以会打印Initialization和Destroyed,中间的Working是super.doAction调用了父类Action的doAction方法,该方法是抽象方法,所以会寻找子类中的实现,找到了Work类中的doAction方法。

posted @ 2016-07-23 23:57  Jiang_Xi  阅读(254)  评论(0编辑  收藏  举报