java - 算术异常 :/by zero only works on integers in Java

Question

为什么将数字除以零会有如此不同的答案:

我的代码:

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);
  }
}

输出:

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

每次我将一个数字除以一个整数(byte、short、int、long)时，它都会抛出 ArithmeticException，而用实数(float、double)时则不会出现这种情况。为什么？

Answer 1

来自 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.

除了:

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