Why doesn't java compiler show a warning for an obvious dividing by zero?

Question

This is just my curiosity to know why java compiler doesn't show any warning in this case while it shows warning for unchecked operations to predict a probable ClassCastException.

public class DivideByZero {
    public static void main() {
        int number = 3/0;
        System.out.println(number);
    }
}

Above code is guaranteed to produce an ArithmeticException.

This is an example only. There are more ways to guarantee a runtime exception without any warning during compilation.

Related: http://stackoverflow.com/questions/2934063/is-1-0-a-legal-java-expression — Sotirios Delimanolis, Sep 29 '13 at 18:49
Because the compiler can't dictate what is "wrong" and what is "right".You may think division by zero is wrong, but some other people could think otherwise. Getting a warning in this case, therefore, would be annoying to them. — One Two Three, Apr 23 '15 at 19:42

score 3 · Answer 1 · answered Sep 29 '13 at 18:44

3

Because technically a divide by zero is a valid program. Compilers only determine the validity of the program not whether there will be a runtime problem. It would be technically incorrect for a compiler to not let you compile a program with a divide by zero since it's valid.

answered Sep 29 '13 at 18:44

Jesus Ramos

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3

That's exactly why he's asking for a _warning_. – SLaks Sep 29 '13 at 18:46
@SLaks missed the part about a warning :\ – Jesus Ramos Sep 29 '13 at 18:46
1

@SLaks Why would he want a warning about perfectly valid and proper use of code? That would be more a job for something akin to checkstyle. – Aaron Sep 29 '13 at 18:48
1

For example, a possible classcast exception is worth a warning because it's potentially bad programming. Whereas dividing by zero is not. – Aaron Sep 29 '13 at 18:51

Why doesn't java compiler show a warning for an obvious dividing by zero?

1 Answers1