快学Scala-08--对象

class Person{
    private var id = 0
    var name= "tom"
    def setId(id:Int) = this.id = id
    def getId() = this.id
}
var p = new Person()
p.name ="Jack"
p.name
res0: String = Jack
p.getId()
p.setId("sandy")
p.name
res1: Int = 0
res2: Unit = ()
res3: Int = 4

var mess="hello"
for(c <- mess)println(c)
mess.apply(3)
mess(3)  //apply 的特殊之处在于可以简化到不写 不用。来调用，默认调用
res1: Char = l
res2: Char = l

class Person2{
    def apply(name:String) = println("hello"+name)
}
var pp = new Person2()
pp.apply("tom")

pp: Person2 = Person2@4ee2a2ac
hellotom
res0: Unit = ()

class Person2{
    var id =0
    var name="hello"
    def this(name:String){  //必须使用this，因为Scala 不能用类名来作为构造方法名
        this() //必须写这一句，因为这一句是默认构造，我们不能定义了构造以后，不管午餐构造
       this.name = name 
    }

}
var pp = new Person2("Jack")
pp.name

pp: Person2 = Person2@1f546f11
res0: String = Jack

5.主构造

class Person(var id:Int=0,var name:String){
}
var p = new Person(1,"Jack");
p.id

需要说明是是 class Person(var id:Int=0,var name:String)