public MetricName metricName(String name, Map<String, String> tags) {
        return explicitMetricName(this.pkg, this.simpleName, name, tags);
    }
@Test
    public void testConstructorWithPackageAndSimpleName() {
        String packageName = "testPackage";
        String simpleName = "testSimple";
        KafkaMetricsGroup group = new KafkaMetricsGroup(packageName, simpleName);
        MetricName metricName = group.metricName("metric-name", Collections.emptyMap());
        assertEquals(packageName, metricName.getGroup());
        assertEquals(simpleName, metricName.getType());
    }