SCJP題庫第021題

1. class Batman{

2.   int squares = 81;

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

4.     new Batman().go();

5.   }

6.   void go(){

7.     incr(++squares);

8.     System.out.println(squares);

9.   }

10. void incr(int squares){squares += 10;}

11. }

What is the result?

A. 81

B. 82

C. 91

D. 92

E. Compilation fails.

F. An exception is thrown at runtime.

Ans:B

解說:

go方法印出的squares是Batman的squares，incr所變更的squares是本身的方法變數

此是在考call by value觀念