我已经实现了一个简单的使用者应用程序来使用来自主题的消息。当我运行kafka消费者应用程序时，出现了以下错误。
堆栈跟踪

org.springframework.context.ApplicationContextException: Failed to start bean 'org.springframework.kafka.config.internalKafkaListenerEndpointRegistry'; nested exception is org.apache.kafka.common.KafkaException: Failed to construct kafka consumer
    at org.springframework.context.support.DefaultLifecycleProcessor.doStart(DefaultLifecycleProcessor.java:185) ~[spring-context-5.2.9.RELEASE.jar:5.2.9.RELEASE]
org.apache.kafka.common.KafkaException: class org.apache.kafka.common.serialization.StringSerializer is not an instance of org.apache.kafka.common.serialization.Deserializer

配置类

@Configuration
@EnableKafka
public class KafkaConfig {
    private ConsumerFactory<String,String> consumerFactory()
    {
        Map<String,Object> config=new ConcurrentHashMap<>();
        config.put(ConsumerConfig.BOOTSTRAP_SERVERS_CONFIG,"127.0.0.1:9092");
        config.put(ConsumerConfig.GROUP_ID_CONFIG,"group_string");
        config.put(ConsumerConfig.KEY_DESERIALIZER_CLASS_CONFIG, StringSerializer.class);
        config.put(ConsumerConfig.VALUE_DESERIALIZER_CLASS_CONFIG,StringSerializer.class);
        return new DefaultKafkaConsumerFactory<>(config);
    }
    @Bean
    public ConcurrentKafkaListenerContainerFactory<String,String> kafkaListenerContainerFactory()
    {
        ConcurrentKafkaListenerContainerFactory<String,String> factory
                =new ConcurrentKafkaListenerContainerFactory<>();
        factory.setConsumerFactory(consumerFactory());
        return factory;
    }
}

侦听器类

@Component
public class KafkaConsumer {
    @KafkaListener(topics = {"Kafka_Example"},groupId = "group_string")
    public void consume(String message)
    {
        System.out.println("Consumed Message "+message);
    }
}

pom.xml文件

<dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.kafka</groupId>
            <artifactId>spring-kafka</artifactId>
            <version>2.6.0</version>
        </dependency>
 <dependency>
            <groupId>org.springframework.kafka</groupId>
            <artifactId>spring-kafka-test</artifactId>
            <version>2.6.0</version>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
            <version>2.11.1</version>
        </dependency>

注意-我的Kafka版本是2.13-2.6.0