使用SpringBoot Kafka Consumer使用ConsumerFactory类获取密钥

Question

 @Bean
    public ConsumerFactory<String,String> consumerFactory() {
        Map<String, Object> configProps = new HashMap<>();
        configProps.put(ConsumerConfig.BOOTSTRAP_SERVERS_CONFIG, "localhost:9092");
        configProps.put(ConsumerConfig.GROUP_ID_CONFIG, UUID.randomUUID().toString());
        configProps.put(ConsumerConfig.KEY_DESERIALIZER_CLASS_CONFIG, StringDeserializer.class);
        configProps.put(ConsumerConfig.VALUE_DESERIALIZER_CLASS_CONFIG, StringDeserializer.class);
        configProps.put("auto.offset.reset", "earliest");
        return new DefaultKafkaConsumerFactory<>(configProps);
    }

    @Bean
    public ConcurrentKafkaListenerContainerFactory<String, String>kafkaListenerContainerFactory() {
        ConcurrentKafkaListenerContainerFactory<String, String>
                factory = new ConcurrentKafkaListenerContainerFactory<>();
        factory.setConsumerFactory(consumerFactory());
        return factory;
    }

    @Bean
    public Receiver receiver(){
        return  new Receiver();
    }


**Receiver class :**
    public class Receiver {

    @KafkaListener(topics = "topicname")
    public void listen(String message) {System.out.println("Kakfa Listener received message " + message);

    }
}

问题是“字符串消息”参数只给我消息，而不给我与Kafka消息相对应的密钥。我想同时检索密钥和消息。如果还有一种获取键值的方法，请回答。