Java Spring boot kafka hello world应用程序无法以“启动”；无法将…下的属性绑定到…”；

我正在使用教程尝试基本的spring boot kafka应用程序

我的项目层次结构如下所示：

SpringBootKafkaApplication.java

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class SpringBootKafkaApplication{
    public static void main(String[] args) {
        SpringApplication.run(SpringBootKafkaApplication.class, args);
    }
}

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

import com.temp.kafka_springboot_pocs.services.Producer;

@RestController
@RequestMapping(value = "/kafka")
public class KafkaController {

    private final Producer producer;

    @Autowired
    public KafkaController(Producer producer) {
        this.producer = producer;
    }

    @PostMapping(value = "/publish")
    public void sendMessageToKafkaTopic(@RequestParam("message") String message) {
        this.producer.sendMessage(message);
    }
}

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.kafka.annotation.KafkaListener;
import org.springframework.stereotype.Service;

@Service
public class Consumer {

    private final Logger logger = LoggerFactory.getLogger(Consumer.class);

    @KafkaListener(topics = "kafka_poc_3", groupId = "group_id")
    public void consume(String message) {
        logger.info(String.format("$$ -> Consumed Message -> %s", message));
    }
}

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.kafka.core.KafkaTemplate;
import org.springframework.stereotype.Service;

@Service
public class Producer {

    private static final Logger logger = LoggerFactory.getLogger(Producer.class);
    private static final String TOPIC = "kafka_poc_3";

    @Autowired
    private KafkaTemplate<String, String> kafkaTemplate;

    public void sendMessage(String message) {
        logger.info(String.format("$$ -> Producing message --> %s",message));
        this.kafkaTemplate.send(TOPIC, message);
    }
}

kafkancontroller.java

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class SpringBootKafkaApplication{
    public static void main(String[] args) {
        SpringApplication.run(SpringBootKafkaApplication.class, args);
    }
}

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

import com.temp.kafka_springboot_pocs.services.Producer;

@RestController
@RequestMapping(value = "/kafka")
public class KafkaController {

    private final Producer producer;

    @Autowired
    public KafkaController(Producer producer) {
        this.producer = producer;
    }

    @PostMapping(value = "/publish")
    public void sendMessageToKafkaTopic(@RequestParam("message") String message) {
        this.producer.sendMessage(message);
    }
}

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.kafka.annotation.KafkaListener;
import org.springframework.stereotype.Service;

@Service
public class Consumer {

    private final Logger logger = LoggerFactory.getLogger(Consumer.class);

    @KafkaListener(topics = "kafka_poc_3", groupId = "group_id")
    public void consume(String message) {
        logger.info(String.format("$$ -> Consumed Message -> %s", message));
    }
}

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.kafka.core.KafkaTemplate;
import org.springframework.stereotype.Service;

@Service
public class Producer {

    private static final Logger logger = LoggerFactory.getLogger(Producer.class);
    private static final String TOPIC = "kafka_poc_3";

    @Autowired
    private KafkaTemplate<String, String> kafkaTemplate;

    public void sendMessage(String message) {
        logger.info(String.format("$$ -> Producing message --> %s",message));
        this.kafkaTemplate.send(TOPIC, message);
    }
}

Consumer.java

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class SpringBootKafkaApplication{
    public static void main(String[] args) {
        SpringApplication.run(SpringBootKafkaApplication.class, args);
    }
}

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

import com.temp.kafka_springboot_pocs.services.Producer;

@RestController
@RequestMapping(value = "/kafka")
public class KafkaController {

    private final Producer producer;

    @Autowired
    public KafkaController(Producer producer) {
        this.producer = producer;
    }

    @PostMapping(value = "/publish")
    public void sendMessageToKafkaTopic(@RequestParam("message") String message) {
        this.producer.sendMessage(message);
    }
}

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.kafka.annotation.KafkaListener;
import org.springframework.stereotype.Service;

@Service
public class Consumer {

    private final Logger logger = LoggerFactory.getLogger(Consumer.class);

    @KafkaListener(topics = "kafka_poc_3", groupId = "group_id")
    public void consume(String message) {
        logger.info(String.format("$$ -> Consumed Message -> %s", message));
    }
}

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.kafka.core.KafkaTemplate;
import org.springframework.stereotype.Service;

@Service
public class Producer {

    private static final Logger logger = LoggerFactory.getLogger(Producer.class);
    private static final String TOPIC = "kafka_poc_3";

    @Autowired
    private KafkaTemplate<String, String> kafkaTemplate;

    public void sendMessage(String message) {
        logger.info(String.format("$$ -> Producing message --> %s",message));
        this.kafkaTemplate.send(TOPIC, message);
    }
}

Producer.java

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class SpringBootKafkaApplication{
    public static void main(String[] args) {
        SpringApplication.run(SpringBootKafkaApplication.class, args);
    }
}

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

import com.temp.kafka_springboot_pocs.services.Producer;

@RestController
@RequestMapping(value = "/kafka")
public class KafkaController {

    private final Producer producer;

    @Autowired
    public KafkaController(Producer producer) {
        this.producer = producer;
    }

    @PostMapping(value = "/publish")
    public void sendMessageToKafkaTopic(@RequestParam("message") String message) {
        this.producer.sendMessage(message);
    }
}

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.kafka.annotation.KafkaListener;
import org.springframework.stereotype.Service;

@Service
public class Consumer {

    private final Logger logger = LoggerFactory.getLogger(Consumer.class);

    @KafkaListener(topics = "kafka_poc_3", groupId = "group_id")
    public void consume(String message) {
        logger.info(String.format("$$ -> Consumed Message -> %s", message));
    }
}

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.kafka.core.KafkaTemplate;
import org.springframework.stereotype.Service;

@Service
public class Producer {

    private static final Logger logger = LoggerFactory.getLogger(Producer.class);
    private static final String TOPIC = "kafka_poc_3";

    @Autowired
    private KafkaTemplate<String, String> kafkaTemplate;

    public void sendMessage(String message) {
        logger.info(String.format("$$ -> Producing message --> %s",message));
        this.kafkaTemplate.send(TOPIC, message);
    }
}

Spring启动应用程序无法启动，错误描述如下：

Failed to bind properties under 'spring.kafka.consumer.value-deserializer' to java.lang.Class<?>:

    Property: spring.kafka.consumer.value-deserializer
    Value: org.apache.kafka.common.serialization.StringDeserialize
    Origin: class path resource [application.properties]:12:42
    Reason: No converter found capable of converting from type [java.lang.String] to type [java.lang.Class<?>]

说明：

Failed to bind properties under 'spring.kafka.consumer.value-deserializer' to java.lang.Class<?>:

    Property: spring.kafka.consumer.value-deserializer
    Value: org.apache.kafka.common.serialization.StringDeserialize
    Origin: class path resource [application.properties]:12:42
    Reason: No converter found capable of converting from type [java.lang.String] to type [java.lang.Class<?>]

无法将“spring.kafka.consumer.value反序列化程序”下的属性绑定到java.lang.Class:
属性：spring.kafka.consumer.value-deserializer
值：org.apache.kafka.common.serialization.StringDeserialize
来源：类路径资源[应用程序.属性]：12:42
原因：未找到能够从类型[java.lang.String]转换为类型[java.lang.Class]的转换器

我错过了什么

---

PS:我在spring和spring boot工作的时间不长。因此，我希望有人能给我一个好的方向/链接，并给出示例或确切的答案。

试试这些属性

#卡夫卡制作人设置 spring.kafka.producer.key serializer=org.apache.kafka.common.serialization.StringSerializer spring.kafka.producer.value serializer=org.apache.kafka.common.serialization.StringSerializer

#卡夫卡消费环境 spring.kafka.consumer.key反序列化器=org.apache.kafka.common.serialization.StringDeserializer spring.kafka.consumer.value反序列化器=org.apache.kafka.common.serialization.StringDeserializer

---

spring.kafka.consumer.auto offset reset=最早的

尝试使用此属性

#卡夫卡制作人设置 spring.kafka.producer.key serializer=org.apache.kafka.common.serialization.StringSerializer spring.kafka.producer.value serializer=org.apache.kafka.common.serialization.StringSerializer

#卡夫卡消费环境 spring.kafka.consumer.key反序列化器=org.apache.kafka.common.serialization.StringDeserializer spring.kafka.consumer.value反序列化器=org.apache.kafka.common.serialization.StringDeserializer

---

spring.kafka.consumer.auto offset reset=earlime

我认为您需要在配置中添加一个消息转换器，或者将字符串消息更改为字节数组，因为在

StringDeserialize

.yikes.之后您只是缺少了一个“r”.这确实是个错误！！！我认为您需要在配置中添加消息转换器，或者将字符串消息更改为字节数组，因为您在

StringDeserialize

.yikes.之后缺少了一个“r”。这确实是个错误！！！