@Test
  public void testBuildingRegistry() {
    CustomTimeBucketRegistry timeBucketRegistry = new CustomTimeBucketRegistry();

    CustomTimeBucket c1m = new CustomTimeBucket(TimeBucket.MINUTE);
    CustomTimeBucket c1h = new CustomTimeBucket(TimeBucket.HOUR);
    CustomTimeBucket c1d = new CustomTimeBucket(TimeBucket.DAY);

    timeBucketRegistry.register(c1m, TimeBucket.MINUTE.ordinal());
    timeBucketRegistry.register(c1h, TimeBucket.HOUR.ordinal());
    timeBucketRegistry.register(c1d, TimeBucket.DAY.ordinal());

    CustomTimeBucket customTimeBucket =
        timeBucketRegistry.getTimeBucket(TimeBucket.MINUTE.ordinal());
    Assert.assertTrue(customTimeBucket.isUnit());
    Assert.assertEquals(TimeBucket.MINUTE, customTimeBucket.getTimeBucket());

    customTimeBucket = timeBucketRegistry.getTimeBucket(TimeBucket.HOUR.ordinal());
    Assert.assertTrue(customTimeBucket.isUnit());
    Assert.assertEquals(TimeBucket.HOUR, customTimeBucket.getTimeBucket());

    customTimeBucket = timeBucketRegistry.getTimeBucket(TimeBucket.DAY.ordinal());
    Assert.assertTrue(customTimeBucket.isUnit());
    Assert.assertEquals(TimeBucket.DAY, customTimeBucket.getTimeBucket());

    Assert.assertEquals(TimeBucket.MINUTE.ordinal(), (int) timeBucketRegistry.getTimeBucketId(c1m));
    Assert.assertEquals(TimeBucket.HOUR.ordinal(), (int) timeBucketRegistry.getTimeBucketId(c1h));
    Assert.assertEquals(TimeBucket.DAY.ordinal(), (int) timeBucketRegistry.getTimeBucketId(c1d));
  }