scala简单的功能实现~weektwo

1、编写⼀个BankAccount类，假如deposit和withdraw⽅法，和⼀个只读的balance属性。

//存款（deposit）和取款（）函数

class BankAccount extends App{
  private  var account:Int=0
  def deposit(money : Int){
    account += money
    println(s"the whole money is $account")
  }
  def withdraw(money : Int){
    //assert(conditon)将在条件不成立的时候，抛出assertionError
    //assert(conditon,explanation)讲在条件不成立的时候，抛出explanation作为说明
    assert(money<=account,"The money you withdraw should be less than account")
    account -=money
    println(s"the whole money is $account")
  }
  def balance=account
}

2、编写Person类，主构造器接受⼀个字符串，字符串形式为名字，空格，姓，如 new Person(“Fred Smith”)。提供只读属性firstName和lastName。

class Person {
  val name="Fred Smith"
  val _name=name.split("\s+")
  val firstName=_name(0)
  val lastName=_name(1)
  override def toString=s"the first name is $firstName,the last name is $lastName"
}

3、定义⼀个Point类，使得我们不⽤new就可以直接使⽤Point(3,4)来构建类的实例。

class Point(val x:Int=0,val y:Int=0) {
  override def toString=("Point x is "+x+",Point y is "+y)
}
object Point{
  def apply(x:Int=0,y:Int=0)=new Point(x,y)
}

4、通过把scala.math.Ordered[Point]混⼊java.awt.Point⽅式，定义OrderedPoint类。按词典⽅式进 ⾏排序，也就是说，如果x1 < x2 或者 x1 = x2 且 y1 < y2, 则(x1,y1) < (x2, y2)