Scala的继承和多态

package com.scala.charpter06

object Extends {
  
  class Person{
    val name = "zhangdan"
    var age = 20
    /*private */  def printHello()=println("------------------------")
  }
  
  
  class Student extends Person{
    //val修饰的属性可以被重写
    override val name:String = "lisi"
    
    //var修饰的属性不可以被重写（编译时报错）
    //override var age = 90
  
    override def printHello(): Unit = {
      super.printHello()
      println("++++++++++++++++++++++")
    }
  }