17.给出下面代码段: public class Test1{ public static void main(String args[]){ int m; switch(m) { case 0:System.out.println("case 0"); case 1:System.out.println("case 1");break; case 2: default:System.out.println("default"); } } } 下列m 的哪个值将引起“default”的输出? A、0 B、1 C、2 D、以上答案都不正确
A B C D
18.下列程序的输出结果为 int j=2; switch(j){ case 2: System.out.println("Value is two."); case 2+1: System.out.println("Value is three."); break; default: System.out.println("Value is "+j); break;} A、Value is two. B、Value is two. Value is three. C、Value is two. Value is three. Value is 2 D、编译错误
A B C D
19.下列哪个类声明是正确的? A、abstract final class Hl{…} B、abstract private move(){…} C、protected private number; D、public abstract class Car{…}