前奏

第一种

class Student(val name:String,val age:Int){
  override def equals(obj: Any): Boolean = {
    val student: Student = obj.asInstanceOf[Student]
    if(name==student.name && age == student.age){
      return true
    }
    return false
  }
}
object Test5{
  def main(args: Array[String]): Unit = {
    val stu = new Student("zs",18)
    if (stu.equals(new Student("zs",18)) ){
      println("match")
    }
  }
}

第二种

if (stu == new Student("zs", 18)){
      println("match")
}

第三种

object Student{
  def apply(name: String, age: Int): Student = new Student(name, age)
  def unapply(arg: Student): Option[(String, Int)] = {
    if (arg == null){
      None
    }else{
      Some((arg.name,arg.age))
    }
  }
}
object Test6{
  def main(args: Array[String]): Unit = {
    val stu = Student("zs",18)
    val res: String = stu match {
      case Student("zs", 18) => "match yes"
      case _ => "Nothing"
    }
    println(res)
  }
}

样例类

case class Teacher(val name:String,val age:Int)
object Test7{
  def main(args: Array[String]): Unit = {
    val teacher = Teacher("ls",30)
    println(teacher match {
      case Teacher("ls", 30) => "teacher name is ls"
      case _ => "Nothing"
    })
  }
}