Scala：Functional Objects

先上代码

 class FunctionalObjects(var _x: Int, var _y: Int) {
   require(_x > 0)
   require(_y > 0)

   def this(value: Int) = this(value, value)

   def x = _x

   def x_=(value: Int) { _x = value }

   def y = _y

   def y_=(value: Int) { _y = value }

   def +(value: Int): FunctionalObjects = {
     _x += value
     _y += value

     this
   }

   def +(value: FunctionalObjects): FunctionalObjects = {
     _x += value.x
     _y += value.y

     this
   }

   override def toString(): String = {
     "("+ _x +", "+ _y +")"
   }
 }

 object FunctionalObjects {
   implicit def intToFunctionalObjectsTest(value: Int) = new FunctionalObjects(value)

   def main(args: Array[String]) {
     var test = new FunctionalObjects(5)
     test.y = 6
     println(test)
     println(test + 4)
     println(4 + test)
   }
 }

隐式类型转换、运算符方法、属性语法，这些都不必多说，大家一看就明白，scala的构造方法得简单的解释一下，类型名称后面跟随的参数列表就是“主要构造函数”的签名，类型定义中出现的可执行语句，都是其方法体。def this 定义的构造方法为“次要构造方法”。