protected MetricGroupId groupId(String groupName, String... tagKeyValues) {
        Map<String, String> tags = MetricsUtils.getTags(tagKeyValues);
        return new MetricGroupId(groupName, tags);
    }
@Test
    public void testMetricGroupIdWithoutTags() {
        MetricGroupId id1 = metrics.groupId("name");
        MetricGroupId id2 = metrics.groupId("name");

        assertEquals(id1.hashCode(), id2.hashCode());
        assertEquals(id1, id2);
        assertEquals(id1.toString(), id2.toString());
        assertEquals(id1.groupName(), id2.groupName());
        assertEquals(id1.tags(), id2.tags());
        assertNotNull(id1.tags());
        assertNotNull(id2.tags());
    }