Why does casting Double.NaN to int not throw an exception in Java?

Question

So I know the IEEE 754 specifies some special floating point values for values that are not real numbers. In Java, casting those values to a primitive int does

Answer 1

Actually i think during some casting there are bit operations done (probably for perf issues?) so that you can have some unexpected behaviours. See what happens when you use >> and << operators.

For exemple:

public static void main(String[] args) {
    short test1 = (short)Integer.MAX_VALUE;
    System.out.println(test1);
    short test2 = (short)Integer.MAX_VALUE-1;
    System.out.println(test2);
    short test3 = (short)Integer.MAX_VALUE-2;
    System.out.println(test3);
    short test4 = (short)Double.MAX_VALUE-3;
    System.out.println(test4);
}

will output:

-1
-2
-3
-4