takipi / loops-jmh-playground Goto Github PK

You probably want to assign the field integers into a local variable inside forMaxInteger(). At the moment your benchmark claims that index based access is 2x slower than iterable/foreach. This is nonsense - you're just reading out of a field not a local variable.

I'll wager quite a lot of money that if you re-write your benchmark as follows that gap disappears:

    public int forMaxInteger() {
        List<Integer> integers = this.integers;
        int max = Integer.MIN_VALUE;
        for (int i = 0; i < size; i++) {
            max = Integer.max(max, integers.get(i));
        }
        return max;
    }