Originally posted by Yuki Cho:
hi guys,
please take a look at the following code with these 3 situation?
1. if the code is the way it is, it prints 1, 2, 3, oops.
2.If i changed y to b in line 6, it prints 1,2, oops.
3. If i changed y to b in line 6 and take out the return keyword in line 14, it prints 1,2, oops, oops
Can you explain to me how to approach these 3 situations?
thanks in advance, yuki
---------------
public class Ace{
public static void main(String argv[]){
int b =1;
for(int y =0; y<4; y++){<br /> try {<br /> if(y > 2) { // line 6
throw new Exception();
}
System.out.println(b);
b++;
}
catch (Exception c){
System.out.println("oops");
return; //line 14
}
}
}
}
Hello Yuki,
I am not very good w/ words. So let's walk together through the code execution for all 3 cases.
Case #1 1 - b = 1
2 - y = 0
3 - in 'try' y is not greater than 2 -> no throw
4 - System.out.println (b) ---->
1 5 - b++ -------> b = 2
6 - no throw in 3 therefore catch loop is not executed, continue w/ for-loop
7 - y = 1
8 - in 'try' y is not greater than 2 -> no throw
9 - System.out.println (b) ---->
2 10 - b++ -------> b = 3
11 - no throw in 8 therefore catch loop is not executed, continue w/ for-loop
12 - y = 2
13 - in 'try' y is not greater than 2 -> no throw
14 -System.out.println (b) ---->
3 15 - b++ -------> b = 4
16 - no throw in 13 therefore catch loop is not executed, continue w/ for-loop
17 - y = 3
18 - in 'try' y is now greater than 2 ---->
throw (i.e. catch block will execute next)
19 - in catch block System.out.println ("
oops")
20 - return and get out of main(). That is how you get your answer of 1, 2, 3, oops
Case #2 1 - b = 1
2 - y = 0
3 - in 'try' b is not greater than 2 -> no throw
4 - System.out.println (b) ---->
1 5 - b++ -------> b = 2
6 - no throw in 3 therefore catch loop is not executed, continue w/ for-loop
7 - y = 1
8 - in 'try' b is not greater than 2 -> no throw
9 - System.out.println (b) ---->
2 10 - b++ -------> b = 3
11 - no throw in 8 therefore catch loop is not executed, continue w/ for-loop
12 - y = 2
13 - in 'try' b is now greater than 2 ---->
throw (i.e. catch block will execute next)
14 - in catch block System.out.println ("
oops")
15 - return and get out of main(). That is how you get your answer of 1, 2, oops
Case #3 1-13 Refer to the first 13 steps in case #2
14 - in catch block System.out.println ("
oops"), continue w/ for-loop (return was removed)
15 - y = 3
16 - in 'try' b is now greater than 2 ---->
throw (i.e. catch block will execute next)
17 - in catch block System.out.println ("
oops"), continue w/ for-loop (return was removed)
18 - y = 4 - for-loop terminates. And that is how you get your answer if 1, 2, oops, oops
Hope that helps answer your question
- Lam -
[This message has been edited by Lam Thai (edited May 13, 2001).]
