@Override public Future<RecordMetadata> send(ProducerRecord<K, V> record) {
    return this.send(record, null);
  }
@Test void send_should_set_name() {
    tracingProducer.send(new ProducerRecord<>(TEST_TOPIC, TEST_KEY, TEST_VALUE));
    mockProducer.completeNext();

    MutableSpan producerSpan = spans.get(0);
    assertThat(producerSpan.kind()).isEqualTo(PRODUCER);
    assertThat(producerSpan.name()).isEqualTo("send");
  }