nanoTime() Test.

NanoTest.java

public class NanoTest
{
    /**
     * usage: NanoTest - run for 100ms and count unique results from System.nanoTest()
     *        NanoText x - run for x ms and count unique results from System.nanoTest()
     * @param args
     */
    public static void main(String[] args)
    {
        final long duration = (args.length > 0 ? Long.parseLong(args[0]) : 100);
        final long startMilli = System.currentTimeMillis();
        long lastNano = System.nanoTime();
        long lastCount = 0;

        long totalDuplicates = 0;
        long totalUniques = 1;

        while ((System.currentTimeMillis() - startMilli) < duration)
        {
            final long thisNano =  System.nanoTime();
            if (thisNano == lastNano)
            {
                lastCount++;
            }
            else
            {
                System.out.println(String.format("nanoTime %s occurred %s times", lastNano, lastCount));
                lastNano = thisNano;
                totalUniques++;
                totalDuplicates += lastCount;
                lastCount = 0;
            }
        }
        System.out.println(String.format("Ran for %s milliseconds, got %s duplicates and %s uniques.", duration, totalDuplicates, totalUniques));
    }
}