模式匹配

case class Pig(name:String)val pig = Pig("pig")pig match {    //需要case class，普通class不可以    //根据传入构造器的参数做精准匹配    case Pig("pig1") => {        println("pig1")    }    case Pig("pig2") => {        println("pig2")    }    case x:Pig => {        println("pig")    }    case _ => {            }}class Match {        def test(x:Int) = x match {        case 1 => {            println("1111111")        }        case 2 => {            println("2222222")        }        //使用守卫        case y if y==3 => {            println("2222222")        }        case _ => {            println("_")        }    }        def test2(obj:Any) = obj match {        case x:String => {            println("is String")        }        case x:Int => {            println("is Int")        }        case _ => {            println("is some other")        }    }        def test3(obj:Option[Any]) = obj match {        case Some(_) => {            println("is Some")        }        case None => {            println("is None")        }        case _ => {            println("is some other")        }    }    }