scala 提取器

package com.xing.listfile

/**
  * Created by DengNi on 2017/2/15.
  */

case class DataWarehouse(name :String ,age :Int)
object ExtrctMethod extends App{

  val dw = DataWarehouse("spark",100) //调用apply 工厂方法 构造出类的实例对象
  val DataWarehouse(name ,age) = dw //调用unapply 方法 dw 实例中的name age  提取出来

  println(name + "  " + age)

  //相当于
  dw match {
    case DataWarehouse(name :String ,age :Int) =>println("1 :::" +name + "  " + age)
  }


//
  val DWCode(tablename ,ages) = DWCode("rmt_stage",12)// 此处用到了  apply 方法 
  println(tablename + "::" + ages)



}
// more example
class DWCode(val tablename :String , val age :Int)
object  DWCode{

  def apply( tablename: String, age: Int): DWCode = new DWCode(  tablename, age)

  def unapply(arg: DWCode): Option[(String, Int)] = {

    Some(arg.tablename,arg.age)

  }

}

scala 提取器