Kotlin-接口

1.接口和java比较类似，也是通过关键字interface来申明一个接口，然后方法的定义是用fun关键字，和java一样不用关键字。

interface Study {
    fun readBooks()
    fun doHomework()
}
//接口的继承
class Student(var sno:String,var grade:Int,name:String,age:Int):Person(name,age),Study{
    constructor(sno: String,grade: Int):this(sno,grade,"",0)
    constructor():this("",0)

    override fun readBooks() {
        TODO("Not yet implemented")
        println(name + "is reading")
    }

    override fun doHomework() {
        TODO("Not yet implemented")
    }
}

2.接口的默认实现

interface Study {
    fun readBooks()
    fun doHomework(){
        println("do homework default")
    }
}