Consider defining a bean of type 'service' in your configuration [Spring boot]

Question

I get error when I run the main class.

Error:

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

TopicService interface:

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);
}

controller:

@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");
    }
}

Implementation class:

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.
    }
}

Rest of the classes are defined too. I don't know why its throwing despite declaring componentScan in main class.

Main class:

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

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

I have my packages like this:

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

Solution 1

A class must have the @Component annotation or a derivation of that (like @Service, @Repository etc.) to be recognized as a Spring bean by the component scanning. So if you add @Component to the class, it should solve your problem.

Solution 2

Since TopicService is a Service class, you should annotate it with @Service, so that Spring autowires this bean for you. Like so:

@Service
public class TopicServiceImplementation implements TopicService {
    ...
}

This will solve your problem.

Solution 3

I fixed the problem adding this line @ComponentScan(basePackages = {"com.example.DemoApplication"}) to main class file, just up from the class name

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);
    }

}

Solution 4

I solved this issue by creating a bean for my service in SpringConfig.java file. Please check the below code,

@Configuration 
public class SpringConfig { 

@Bean
public TransactionService transactionService() {
    return new TransactionServiceImpl();
}

}

The path of this file is shown in the below image, Spring boot application folder structure

Solution 5

You are trying to inject a bean in itself. That's obviously not going to work.

TopicServiceImplementation implements TopicService. That class attempts to autowire (by field!) a `TopicService. So you're essentially asking the context to inject itself.

It looks like you've edited the content of the error message: Field topicService in seconds47.restAPI.topics is not a class. Please be careful if you need to hide sensitive information as it makes it much harder for others to help you.

Back on the actual issue, it looks like injecting TopicService in itself is a glitch on your side.

View more solutions

Comments

[kittu]

I didn't understand a thing when you said I am injecting a bean in itself ?? I am injecting TopicService which is a interface into a controller class Topics

[kittu]

I didn't edit the error message. I just edited the question title I have posted

[kittu]

Still the problem exists. I removed @Autowired private TopicService topicService; from implementation class

[Tushar Banne]

I am getting that error even if I have annotated that class with @Component

[Sumit Rane]

@Service annotation I applied on the interface that's why I was facing the same problem, after applying it on implementation class it worked for me

[Zhenyria]

@TusharBanne it will not work if you use annotation for interface of bean, not for bean