UnsatisfiedDependencyException:使用name创建bean时出错

Question

有几天我正在尝试创建Spring CRUD应用程序.我糊涂了.我无法解决这个错误.

org.springframework.beans.factory.UnsatisfiedDependencyException:创建名为'clientController'的bean时出错:通过方法'setClientService'参数0表示不满意的依赖关系; 嵌套异常是org.springframework.beans.factory.UnsatisfiedDependencyException:创建名为'clientService'的bean时出错:通过字段'clientRepository'表示的不满意的依赖关系; 嵌套异常是org.springframework.beans.factory.NoSuchBeanDefinitionException:没有类型'com.kopylov.repository.ClientRepository'的限定bean可用:预期至少有1个bean有资格作为autowire候选者.依赖注释:{@ org.springframework.beans.factory.annotation.Autowired(required = true)}

还有这个

org.springframework.beans.factory.UnsatisfiedDependencyException:创建名为'clientService'的bean时出错:通过字段'clientRepository'表示的不满意的依赖关系; 嵌套异常是org.springframework.beans.factory.NoSuchBeanDefinitionException:没有类型'com.kopylov.repository.ClientRepository'的限定bean可用:预期至少有1个bean有资格作为autowire候选者.依赖注释:{@ org.springframework.beans.factory.annotation.Autowired(required = true)}

ClientController

@Controller
public class ClientController {
private ClientService clientService;

@Autowired
@Qualifier("clientService")
public void setClientService(ClientService clientService){
    this.clientService=clientService;
}
@RequestMapping(value = "registration/add", method = RequestMethod.POST)
public String addUser(@ModelAttribute Client client){
    this.clientService.addClient(client);
return "home";
}
}

ClientServiceImpl

@Service("clientService")
public class ClientServiceImpl implements ClientService{

private ClientRepository clientRepository;

@Autowired
@Qualifier("clientRepository")
public void setClientRepository(ClientRepository clientRepository){
    this.clientRepository=clientRepository;
}



@Transactional
public void addClient(Client client){
    clientRepository.saveAndFlush(client);
}
}

ClientRepository

public interface ClientRepository extends JpaRepository<Client, Integer> {

}

我查看了很多类似的问题,但没有人回答他们无法帮助我.

Answer 1

ClientRepository应使用@Repository标记进行注释.使用您当前的配置,Spring将不会扫描该类并了解它.在启动和连线的那一刻将找不到ClientRepository类.

编辑 如果添加@Repository标记没有帮助,那么我认为问题可能现在与ClientService和ClientServiceImpl.

尝试使用注释ClientService(接口)@Service.由于您的服务只应该有一个实现,因此您无需使用可选参数指定名称@Service("clientService").Spring将根据接口名称自动生成它.

此外,正如Bruno所提到的那样,因为您只有一个服务实现,所以@Qualifier不需要ClientController.

ClientService.java

@Service
public interface ClientService {

    void addClient(Client client);
}

ClientServiceImpl.java(选项1)

@Service
public class ClientServiceImpl implements ClientService{

    private ClientRepository clientRepository;

    @Autowired
    public void setClientRepository(ClientRepository clientRepository){
        this.clientRepository=clientRepository;
    }

    @Transactional
    public void addClient(Client client){
        clientRepository.saveAndFlush(client);
    }
}

ClientServiceImpl.java(选项2 /首选)

@Service
public class ClientServiceImpl implements ClientService{

    @Autowired
    private ClientRepository clientRepository;

    @Transactional
    public void addClient(Client client){
        clientRepository.saveAndFlush(client);
    }
}

ClientController.java

@Controller
public class ClientController {
    private ClientService clientService;

    @Autowired
    //@Qualifier("clientService")
    public void setClientService(ClientService clientService){
        this.clientService=clientService;
    }

    @RequestMapping(value = "registration", method = RequestMethod.GET)
    public String reg(Model model){
        model.addAttribute("client", new Client());
        return "registration";
    }

    @RequestMapping(value = "registration/add", method = RequestMethod.POST)
    public String addUser(@ModelAttribute Client client){
        this.clientService.addClient(client);
    return "home";
    }
}

Answer 2

我知道这似乎为时已晚，但将来可能会对其他人有所帮助。

我遇到了同样的错误，问题是 spring boot 没有读取我的服务包，所以添加：

@ComponentScan(basePackages = {"com.example.demo.Services"})（您必须指定自己的服务包路径）和类 demoApplication（具有主要功能的类）和服务接口必须注释 @Service，实现服务接口的类必须用 注释@Component，然后自动装配服务接口。

Answer 3

尝试在主类的顶部添加 @EntityScan(basePackages = "insert package name here")。

Answer 4

If you are using Spring Boot, your main app should be like this (just to make and understand things in simple way) -

package aaa.bbb.ccc;
@SpringBootApplication
@ComponentScan({ "aaa.bbb.ccc.*" })
public class Application {
.....

Make sure you have @Repository and @Service appropriately annotated.

Make sure all your packages fall under - aaa.bbb.ccc.*

In most cases this setup resolves these kind of trivial issues. Here is a full blown example. Hope it helps.