Scala学习笔记

1 闭包

     var a = 3
     var addfun = (x:Int) => x + a
     var b = addfun(10)
     println(b)

　　

addfun 就是个和对象无关的函数，局部变量，使用方法和函数一样，但是好像不推荐这种写法。


2 类的创建，简单使用

abstract class BParent{
  def testoverride()
}

// 构造函数参数会自动生成类字段,如果不加val则为私有字段, 类外无法访问
class B( val name : String, val age:Int) extends  BParent{
  var namebak:String=_ // 初始化
  val cname = "classname is B"

  // 附属构造器, C++ 重载构造函数
  def this(name: String, age: Int, namebak: String){
    this(name, age)
    println("call this " + name)
    this.namebak = namebak
  }

  def testoverride(): Unit ={
    println("my class name is B")
  }
}

class BSon(name: String, age: Int, addr: String) extends B(name, age){
  println("Bson is Create")


  override val cname = "classname is BSon"

  override def toString = "BSon toString "  + super.toString

  override  def testoverride(): Unit ={
    println("my class name is BSon")
  }
}

　　

　　调用

val b = new B("test", 32, "dd")
println(b.name)
println(b.namebak)
println(b.toString)

var bson = new BSon("bsonname", 1, "bsonaddr")
println(bson.toString)
println(bson.cname)
bson.testoverride()

 

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