Java考试格林练习题

question 11)

what will be the result of attempting to compile and run the following code?

abstract class minebase { abstract void amethod(); static int i;}public class mine extends minebase { public static void main(string argv[]){ int[] ar=new int[5]; for(i=0;i < th;i++) tln(ar[i]); }}

1) a sequence of 5 0’s will be printed

2) error: ar is used before it is initialized

3) error mine must be declared abstract

4) indexoutofboundes error

question 12)

what will be printed out if you attempt to compile and run the following code ?

int i=1; switch (i) { case 0: tln("zero"); break; case 1: tln("one"); case 2: tln("two"); default: tln("default"); }

1) one

2) one, default

3) one, two, default

4) default

question 13)

what will be printed out if you attempt to compile and run the following code?

int i=9;switch (i) { default: tln("default"); case 0: tln("zero"); break; case 1: tln("one"); case 2: tln("two");}

1) default

2) default, zero

3) error default clause not defined

4) no output displayed