assertions in try-catch blocks

[catherine powell]

From Whizlabs 1.4 Mock...

Which of the following statements about assertions are true? (choose 2)
A. Assertions are by default enabled in JDK 1.4, during compilation and runtime.
B. In assert syntax - assert expression1; the expression1 must be a boolean expression.
C. In assert syntax - assert expression1; the expression1 must be an expression resulting in an int.
D. An assert statement may not be enclosed in a try-catch block.
E. Only option B is correct.

I picked B & E. Whizlabs states B and D are correct.
I agree with B but don't understand why D is correct.

The following codes compiles (using -source 1.4 switch) and runs as expected (using -ea):

public class AssertTC{
public static void main(String[] args){
try{
int x=1;
assert (x==2);
}catch(Throwable t){
System.out.println("caught!");
}
}
}

Can someone please explain why D should be marked correct?
Thank you very much in advance...Catherine

[Scott Johnson]

I agree that option D is not true. There is no rule that keeps you from putting assert statements inside a try/catch.

[wise owen]

The assertion is specifically designed for debugging, no try-catch block is necessary.

[Joe San]

Hi Catherine,

Even I picked the same result as B&E and got the same feedback that B&D are correct. We can put the assert condition in a try catch block though it is not necessary.

Regards,
Jothi Shankar Kumar. S

[catherine powell]

I agree that logically it doesn't make any sense to put an assertion in a try-catch. However, the way that option D was phrased, I thought it was an issue of legal vs. illegal code.

Hopefully, I won't see a question worded in a similar way on the real test.

Thank you guys very much for your help...Catherine

BTW, this question is from the 1.4 Diagnostic Test, Question #33.

[Burkhard Hassel]

Hi Ranchers,

Catherine wrote

I agree that logically it doesn't make any sense to put an assertion in a try-catch. However, the way that option D was phrased, I thought it was an issue of legal vs. illegal code.

Hopefully, I won't see a question worded in a similar way on the real test.

Yes, that's a silly question from whizlabs and should be approved.

And yes, putting an assertion in a try catch block is totally against the sense of assertions:

class Main {
public static void main(String[] args) {
try {
assert false:"eek!";
} catch (AssertionError ae) {
System.err.println("Gotcha, bastard!");
}
System.out.println ("main ready");
}
}

legal, but not appropriate, but what's "may not be" ?
It should be clear if they meant "legal" or "appropriate". And also it's not appropriate in the public main() method.




By the way, did you spot the paradoxon in answer E ?





Yours,
Bu.