第146題

Given:
1. import java.io.*;
2. public class Foo implements Serializable{
3. public int x, y;
4. public Foo(int x, int y){this.x = x; this.y = y;}
5.
6. private void writeObject(ObjctOutputStream s)
7. throws IOException{
8. s.writeInt(x); s.writeInt(y);
9. }
10.
11. private void readObject(ObjectInputStream s)
12. throws IOException, ClassNotFoundException{
13.
14. //insert code here
15.
16. }
17. }

Which code, inserted at line 14, will allow this class to correctly serialize and deserialize?
A. s.defaultReadObject();
B. this = s.defaultReadObject(),
C. y = s.readInt(); x = s.readInt();
D. x = s.readInt(); y = s.readInt();
答案：D
參考：10-5 多重串接

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writeObject 是專門序列化的方法, 裡面先寫入
s.writeInt(x); s.writeInt(y);
readObject 反序列化就是把他讀取出來.
所以x = s.readInt(); y = s.readInt();