spring - 启动（创建 bean 时出错） - org.springframework.beans.factory.UnsatisfiedDependencyException：使用名称创建 bean 时出错

Question

尝试使用 jpa/hibernate 创建一个基本的 web 服务。 但是bean没有被初始化。 谁可以帮我这个事？

下面是我的 CustomerController.java：

@RestController
public class CustomerController {

    @Autowired
    CustomerService service;

    @SuppressWarnings("deprecation")
    @PostMapping(value = "/getCust", consumes=MediaType.APPLICATION_JSON_UTF8_VALUE, produces = MediaType.APPLICATION_JSON_UTF8_VALUE)
    public List<CustomerModel> retriveCustomers(@RequestBody CustomerModel cust){
        System.out.println(cust); //just to see the object in console
        List<CustomerModel> resp = service.getCustomers();
        return resp;
    }
}

下面是我的 CustomerService.java：

@Service
public class CustomerService {

    @Autowired
    CustomerRepository repo;

    public List<CustomerModel> getCustomers() {
        List<CustomerModel> resp=repo.getAllCustomers();
        return resp;
    }


}

下面是我的 CustomerRepository.java：

@Repository
public interface CustomerRepository extends CrudRepository<CustomerModel, Integer>{

    List<CustomerModel> getAllCustomers();
}

下面是我的 CustomerModel.java：

@Entity
@Table(name="aliens")
public class CustomerModel {

    @Id
    @Column(name="customer_id")
    private String customerId;

    @Column(name="customer_name")
    private String customerName;

    @Column(name="customer_email")
    private String customerEmail;

    @Column(name="customer_phoneNum")
    private String customerPhoneNum;

    @Column(name="customer_password")
    private String customerPassword;


}

org.springframework.beans.factory.UnsatisfiedDependencyException：创建名为“customerController”的bean时出错：通过字段“service”表示的依赖关系不满足； 嵌套异常是 org.springframework.beans.factory.UnsatisfiedDependencyException：创建名称为“customerService”的 bean 时出错：通过字段“repo”表示不满足的依赖关系； 嵌套异常是 org.springframework.beans.factory.BeanCreationException：创建名为“customerRepository”的 bean 时出错：调用 init 方法失败； nested exception is java.lang.IllegalArgumentException: Failed to create query for method public abstract java.util.List com.ekart.fabfeet.service.CustomerRepository.getAllCustomers()! 没有找到类型 CustomerModel 的属性 getAllCustomers！

org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:639) ~[spring-beans-5.2.0.RELEASE.jar:5.2.0.RELEASE] at org.springframework.beans.factory .annotation.InjectionMetadata.inject(InjectionMetadata.java:116) ~[spring-beans-5.2.0.RELEASE.jar:5.2.0.RELEASE] at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessProperties(AutowiredAnnotationBeanPostProcessor. java:397) ~[spring-beans-5.2.0.RELEASE.jar:5.2.0.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1429) ~[spring-beans -5.2.0.RELEASE.jar:5.2.0.RELEASE] 在 org.srin gframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:594) ~[spring-beans-5.2.0.RELEASE.jar:5.2.0.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory .createBean(AbstractAutowireCapableBeanFactory.java:517) ~[spring-beans-5.2.0.RELEASE.jar:5.2.0.RELEASE] at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java :323) ~[spring-beans-5.2.0.RELEASE.jar:5.2.0.RELEASE] at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) ~[spring-beans- 5.2.0.RELEASE.jar:5.2.0.RELEASE] 在 org.springframework.beans.factory.support.AbstractBeanFacto ry.doGetBean(AbstractBeanFactory.java:321) ~[spring-beans-5.2.0.RELEASE.jar:5.2.0.RELEASE] at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:202 ) ~[spring-beans-5.2.0.RELEASE.jar:5.2.0.RELEASE] at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.Z93F725A07423FE1C889F448B33D22) 0.RELEASE.jar:5.2.0.RELEASE] at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:878) ~[spring-context-5.2.0.RELEASE.jar:5.2.0.RELEASE ] 在 org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:550) ~[spri ng-context-5.2.0.RELEASE.jar:5.2.0.RELEASE] at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:141) ~[spring-boot-2.2.0 .RELEASE.jar:2.2.0.RELEASE] at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:747) [spring-boot-2.2.0.RELEASE.jar:2.2.0.RELEASE] at org. springframework.boot.SpringApplication.refreshContext(SpringApplication.java:397) [spring-boot-2.2.0.RELEASE.jar:2.2.0.RELEASE] at org.springframework.boot.SpringApplication.run(SpringApplication.java:315) [spring-boot-2.2.0.RELEASE.jar:2.2.0.RELEASE] 在 org.springframework.boot.SpringApplication.run(SpringApplication.Z93F725A0742 3FE1C889F448B33D21F46Z:1226) [spring-boot-2.2.0.RELEASE.jar:2.2.0.RELEASE] at org.springframework.boot.SpringApplication.run(SpringApplication.java:1215) [spring-boot-2.2.0.RELEASE .jar:2.2.0.RELEASE]

Answer 1

在 CrudRepository 你可以使用 findAll() 方法，文档在这里

当列出对象时，我建议您从 PagingAndSortingRepository 扩展，在那里您将完成分页和排序的实现，这非常方便。

关于错误，您可以在此处找到正确的语法（getAll 不存在，您应该使用 findAll）。

Answer 2

在您的存储库中，您正在扩展CrudRepository<CustomerModel, Integer> ，但您的实体的 ID 列是字符串，而不是 integer。

这就是它无法为您匹配存储库的原因。 将其修复为字符串，它应该可以正常工作

Answer 3

显然他正在尝试实现QueryMethods ，在这种情况下方法签名不正确， QueryMethods是 model ，其中查询是根据实体属性的名称和方法名称中支持的关键字构建的。