Arithmetic Exception: / by zero only works on integers in Java

Question

Why such different answers on dividing a number by zero:

My code:

class Test {
  public static void main(String[] args){

    int a = (int)(3/0.0F);
    System.out.println(a);

    System.out.println(3/0.0F);

    System.out.println(3/0);
  }
}

Output:

2147483647
Infinity
Exception in thread "main" java.lang.ArithmeticException: / by zero

Every time I divide a number by an integer (byte, short, int, long) it throws ArithmeticException, which is not the case when done with real numbers (float, double). Why?

Answer 1

From JLS §15.17.2:

• Division of a nonzero finite value by a zero results in a signed infinity. The sign is determined by the rule stated above.

with the exception that:

if the value of the divisor in an integer division is 0, then an ArithmeticException is thrown.