第100題

Given:

10. public class SuperCalc{
11. protected static int multiply(int a, int b){return a * b;}
12. }
and:
20. public class SubCalc extends SuperCalc{
21. public static int multiply(int a, int b){
22. int c = super.multiply(a, b);
23. return c;
24. }
25. }
and:
30. SubCalc sc = new SubCalc();
31. System.out.println(sc.multiply(3, 4));
32. System.out.println(SubCalc.multiply(2, 2));
What is the result?
A. 12
B. The code runs with no output.
C. An exception is thrown at runtime.
D. Compilation fails because of an error in line 21.
E. Compilation fails because of an error in line 22.
F. Compilation fails because of an error in line 31.
答案：E
參考：8-2 方法種類與呼叫方式

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public static int multiply(int a, int b) 是 static 方法, 裡面不可以放 super 或 this 關鍵字