UnsatisfiedDependencyException:使用名称创建 bean 时出错 [英] UnsatisfiedDependencyException: Error creating bean with name

问题描述

几天来，我一直在尝试创建 Spring CRUD 应用程序.我糊涂了.我无法解决这个错误.

For several days I'm trying to create Spring CRUD application. I'm confused. I can't solve this errors.

org.springframework.beans.factory.UnsatisfiedDependencyException:创建名为clientController"的 bean 时出错:通过方法setClientService"参数 0 表达的不满意依赖；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"表达的不满意的依赖；嵌套异常是 org.springframework.beans.factory.NoSuchBeanDefinitionException:没有可用的com.kopylov.repository.ClientRepository"类型的合格 bean:预计至少有 1 个 bean 有资格作为自动装配候选.依赖注解:{@org.springframework.beans.factory.annotation.Autowired(required=true)}

org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'clientController': Unsatisfied dependency expressed through method 'setClientService' parameter 0; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'clientService': Unsatisfied dependency expressed through field 'clientRepository'; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'com.kopylov.repository.ClientRepository' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {@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"表达的不满意依赖；嵌套异常是 org.springframework.beans.factory.NoSuchBeanDefinitionException:没有可用的com.kopylov.repository.ClientRepository"类型的合格 bean:预计至少有 1 个 bean 有资格作为自动装配候选.依赖注解:{@org.springframework.beans.factory.annotation.Autowired(required=true)}

org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'clientService': Unsatisfied dependency expressed through field 'clientRepository'; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'com.kopylov.repository.ClientRepository' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}

客户端控制器

@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> {

}

我浏览了很多类似的问题，但没有人能帮到我.

I looked through a lot of similar questions, but no one answer to them can't help me.

推荐答案

ClientRepository 应该使用 @Repository 标签进行注释.使用您当前的配置，Spring 不会扫描类并了解它.在启动和接线的时候不会找到 ClientRepository 类.

The ClientRepository should be annotated with @Repository tag. With your current configuration Spring will not scan the class and have knowledge about it. At the moment of booting and wiring will not find the ClientRepository class.

编辑如果添加 @Repository 标记没有帮助，那么我认为问题现在可能出在 ClientService 和 ClientServiceImpl 上.

EDIT If adding the @Repository tag doesn't help, then I think that the problem might be now with the ClientService and ClientServiceImpl.

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

Try to annotate the ClientService (interface) with @Service. As you should only have a single implementation for your service, you don't need to specify a name with the optional parameter @Service("clientService"). Spring will autogenerate it based on the interface' name.

此外，正如布鲁诺所提到的，ClientController 中不需要 @Qualifier，因为您只有一个服务实现.

Also, as Bruno mentioned, the @Qualifier is not needed in the ClientController as you only have a single implementation for the service.

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";
    }
}

这篇关于UnsatisfiedDependencyException:使用名称创建 bean 时出错的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！