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