@Test
public void testDropwizardDs() {

    MetricRegistry reg = new MetricRegistry();
    DropWizardMetricsRegistry dwreg = new DropWizardMetricsRegistry(Clock.SYSTEM, reg);
    DistributionSummary ds = dwreg.distributionSummary(dwreg.createId("a.b.c"));
    ds.record(3);
    ds.record(3);
    Histogram histogram = reg.histogram("a.b.c");
    System.out.println(histogram.getCount());
    Assert.assertEquals(2, histogram.getCount());
}