Scala Automatic String Conversion

原创转载请注明出处：http://agilestyle.iteye.com/blog/2333708

 

创建一个case类时会自动创建toString方法，并且nice输出

创建一个非Case类时也会自动创建toString方法，但是ugly输出为对象在JVM中的内存的HashCode

要得到更有用的结果，就得override自己的toString方法

package org.fool.scala.strings

case class Teacher(name: String)

class Student(val age: Int)

class Student2(val age: Int) {
  override def toString: String = s"Student is $age years old"
}

object ToStringTest extends App {
  val teacher = Teacher("SB")
  // Teacher(SB)
  println(teacher)

  val student = new Student(18)
  // org.fool.scala.strings.Student@6bf256fa
  println(student)

  // Student is 30 years old
  val student2 = new Student2(30)
  println(student2)
}

Console Output