考虑在您的配置中定义一个“服务”类型的 bean \[Spring boot\]

Question

运行主类时出现错误。

错误：

 Action:
Consider defining a bean of type 'seconds47.service.TopicService' in your configuration.

Description:
Field topicService in seconds47.restAPI.topics required a bean of type 'seconds47.service.TopicService' that could not be found

主题服务接口：

 public interface TopicService {

    TopicBean findById(long id);

    TopicBean findByName(String name);

    void saveTopic(TopicBean topicBean);

    void updateTopic(TopicBean topicBean);

    void deleteTopicById(long id);

    List<TopicBean> findAllTopics();

    void deleteAllTopics();

    public boolean isTopicExist(TopicBean topicBean);
}

控制器：

 @RestController
public class topics {

    @Autowired
    private TopicService topicService;

    @RequestMapping(path = "/new_topic2", method = RequestMethod.GET)
    public void new_topic() throws Exception {
        System.out.println("new topic JAVA2");
    }
}

实现类：

 public class TopicServiceImplementation implements TopicService {

    @Autowired
    private TopicService topicService;

    @Autowired
    private TopicRepository topicRepository;

    @Override
    public TopicBean findById(long id) {
        throw new UnsupportedOperationException("Not supported yet."); //To change body of generated methods, choose Tools | Templates.
    }

    @Override
    public TopicBean findByName(String name) {
        throw new UnsupportedOperationException("Not supported yet."); //To change body of generated methods, choose Tools | Templates.
    }

    @Override
    public void saveTopic(TopicBean topicBean) {
        throw new UnsupportedOperationException("Not supported yet."); //To change body of generated methods, choose Tools | Templates.
    }

    @Override
    public void updateTopic(TopicBean topicBean) {
        throw new UnsupportedOperationException("Not supported yet."); //To change body of generated methods, choose Tools | Templates.
    }

    @Override
    public void deleteTopicById(long id) {
        throw new UnsupportedOperationException("Not supported yet."); //To change body of generated methods, choose Tools | Templates.
    }

    @Override
    public List<TopicBean> findAllTopics() {
        throw new UnsupportedOperationException("Not supported yet."); //To change body of generated methods, choose Tools | Templates.
    }

    @Override
    public void deleteAllTopics() {
        throw new UnsupportedOperationException("Not supported yet."); //To change body of generated methods, choose Tools | Templates.
    }

    @Override
    public boolean isTopicExist(TopicBean topicBean) {
        throw new UnsupportedOperationException("Not supported yet."); //To change body of generated methods, choose Tools | Templates.
    }
}

其余的类也被定义。尽管在主类中声明了 componentScan ，但我不知道为什么它会抛出。

主类：

 @SpringBootApplication(exclude = {SecurityAutoConfiguration.class })
@ComponentScan(basePackages = {"seconds47"})
@EnableJpaRepositories("seconds47.repository")
public class Application {

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

我有这样的包裹：

 seconds47
seconds47.beans
seconds47.config
seconds47.repository
seconds47.restAPI
seconds47.service

原文由 kittu 发布，翻译遵循 CC BY-SA 4.0 许可协议

Answer 1

一个类必须具有 @Component 注释或其派生（如 @Service ， @Repository 等）才能被组件扫描识别为 Spring bean。因此，如果您将 @Component 添加到课程中，它应该可以解决您的问题。

原文由 dunni 发布，翻译遵循 CC BY-SA 3.0 许可协议

Answer 2

我解决了将这一行添加到主类文件中的问题 @ComponentScan(basePackages = {"com.example.DemoApplication"}) 从类名开始

package com.example.demo;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.ComponentScan;

@SpringBootApplication
@ComponentScan(basePackages = {"com.example.DemoApplication"})
public class DemoApplication {

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

}

原文由 Luis Alfredo Serrano Díaz 发布，翻译遵循 CC BY-SA 4.0 许可协议