SCJP題庫第142題

Assuming that the serializeBanana() and the deserializeBanana() methods will correctly use Java serialization and given:

13. import java.io.*;

14. class Food implements Serializable{int good = 3;}

15. class Fruit extends Food{int juice = 5;}

16. public class Banana extends Fruit{

17.   int yellow = 4;

18.   public static void main(String[] args) {

19.     Banana b = new Banana(); Banana b2 = new Banana();

20.     b.serializeBanana(b); //assume correct serialization

21.     b2 = b.deserializeBanana(); //assume correct

22.     System.out.println("restore " + b2.yellow + b2.juice + b2.good);

24.   }

25. //more Banana methods go here

50. }

What is the result?

A. restore 400

B. restore 403

C. restore 453

D. Compilation fails.

E. An exception is thrown at runtime.

 

Ans: C

 

解說:

物件的串流操作，serialize和deserialize可看做是將物件放入或取出一個磁帶