scala对象

类的定义

class People {
    val age:Int = 10
    var name:String = _
    var des:String = ""
}

修饰符

private [this] val age = 10

构造方法

// 主构造器
class Persion(val name:String, val age: Int){

    def this(name: String, age: Int, gender: String) {
        this(name, age) //附属构造器的第一行代码必须要调用主构造器或者其它构造器
    }

}

重写

override def toString: String = "tdo to println"

伴生对象和伴生类

class ApplyTest { //对象
    def apply() = {
        1
    }
}

Object ApplyTest { //函数
    def apply() = {
        new ApplyTest()
    }
}

val b = ApplyTest() // ==> ApyylyTest的class实例
b.apply // ===> 1

case class

// 通常用在模式匹配
case class Dog(name: String)

println(Dog("wanc").name)

接口

• 定义接口

Tarit xxx
class xxx extends xx with xx with xx