int vs long vs short benchmark

package benchmark;

public class Bench {
    private static final int ITERATIONS = 1000000000;

    public static void main(String[] args) {
        benchmarkInt();
        benchmarkLong();
        benchmarkShort();
    }

    private static void benchmarkInt() {
        // Create two variables that both equal 1, but that the compiler won't
        // optimize away inside the loop.
        final int a = (int)Math.ceil(Math.random());
        final int b = (int)Math.ceil(Math.random());
        // Do the benchmark three times, allowing the user to see the variation.
        for (int test = 0; test < 3; test++) {
            int t = 0;
            long start = System.nanoTime();
            for (int i = 0; i < ITERATIONS; i++) {
                t += a;
                t -= b;
            }
            long duration = System.nanoTime() - start;
            // Print benchmark result. First result should probably be ignored,
            // it's the warmup phase.
            System.out.println("int: " + duration / 1000000 + " ms. Calculation result: " + t);
        }
    }

    private static void benchmarkLong() {
        final long a = (long)Math.ceil(Math.random());
        final long b = (long)Math.ceil(Math.random());
        for (int test = 0; test < 3; test++) {
            long t = 0;
            long start = System.nanoTime();
            for (int i = 0; i < ITERATIONS; i++) {
                t += a;
                t -= b;
            }
            long duration = System.nanoTime() - start;
            System.out.println("long: " + duration / 1000000 + " ms. Calculation result: " + t);
        }
    }

    private static void benchmarkShort() {
        final short a = (short)Math.ceil(Math.random());
        final short b = (short)Math.ceil(Math.random());
        for (int test = 0; test < 3; test++) {
            short t = 0;
            long start = System.nanoTime();
            for (int i = 0; i < ITERATIONS; i++) {
                t += a;
                t -= b;
            }
            long duration = System.nanoTime() - start;
            System.out.println("short: " + duration / 1000000 + " ms. Calculation result: " + t);
        }
    }
}