Serialization demo in scala

SerializationDemo.scala

import java.io._

@SerialVersionUID(124L)
class Person(var name: String)
extends Serializable {
    override def toString = f"My name is $name%s."
}

@SerialVersionUID(123L)
class Pet(var name: String, var species: String, var owner: Person)
extends Serializable {
    override def toString = {
        val ownerName = owner.name
        f"$ownerName%s has a $species%s named $name%s"
    }
}

object SerializationDemo extends App {

    // init person and pet
    val person = new Person("Truman Wu")
    val pet = new Pet("Jojo", "dog", person)
    
    // serialize two associated objects into the tmp file
    val oos = new ObjectOutputStream(new FileOutputStream("./pets2persons"))
    oos.writeObject(person)
    oos.writeObject(pet)
    oos.close
    
    // deserialize the two objects from the file created above
    val ois = new ObjectInputStream(new FileInputStream("./pets2persons"))
    val personOutput = ois.readObject()
    val petOutput = ois.readObject()
    ois.close
    println(personOutput)
    println(petOutput)
}