Question

I have this code that runs but never stops.

class A {
   public static void main(String[] args) {
      for (byte index = 0; index < 128; index++)
      {
          System.out.println(index);
      }
   }
}

Can someone explain to me why it keeps looping.

Answer 1

In Java, byte can only represent values between -128 and 127. This means that every possible value of index is less than 128, and the loop cannot terminate with the current condition. When index reaches 127, it simply overflows to -128 and the loop carries on.

For more details on Java’s integral types, see the JLS.