第46題
Given:
10. public class Pizza{
11. ArrayList toppings;
12.
13. public final void addTopping(String topping){
14. toppings.add(topping);
15. }
16.
17. public void removeTopping(String topping){
18. toppings.remove(topping);
19. }
20. }
And:
30. class PepperoniPizza extends Pizza{
31. public void addTopping(String topping){
32. System.out.println("Cannot add Toppings");
33. }
34.
35. public void removeTopping(String topping){
36. System.out.println("Cannot remove pepperoni");
37. }
38. }
And:
50. Pizza pizza = new PepperoniPizza();
SCJP 6.0 認證教戰手冊 黃彬華著 碁峰出版
25
51. pizza.addTopping("Mushrooms");
52. pizza.removeTopping("Pepperoni");
What is the result?
(A) Compilation fails.
(B) Cannot add Toppings
(C) The code runs with no output.
(D) A NullPointerException is thrown in Line 4.
阿摩線上測驗
登入
