package com.aura.scala.day01object sealedClassed {  def findPlaceToSit(piece: Furniture) = piece match {    case a: Couch => "Lie on the couch"    case b: Chair => "Sit on the chair"  }}//sealed定义密封类sealed abstract class  Furniturecase class Couch() extends Furniturecase class Chair() extends Furniture