SCJP題庫第100題


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  4
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.
 
Ans: E
 
解說:
Super只能用來存取物件成員
22行須改為
int c = SuperCalc.multiply(a, b);

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