Map<MetricName, ? extends Metric> metrics() {
        return producer.metrics();
    }
@SuppressWarnings({"rawtypes", "unchecked"})
    @Test
    public void shouldForwardCallToMetrics() {
        final Map metrics = new HashMap<>();
        when(mockedProducer.metrics()).thenReturn(metrics);

        assertSame(metrics, streamsProducerWithMock.metrics());
    }