使用 Spring Boot + Jpa + vaadin 保存表单数据时出现问题

Question

我正在使用 SpringBoot 以及 JPA 和 Vaadin-flow。我在尝试保存表单数据时遇到此错误。

我尝试在 CustomerRepository class 中添加 @Repository 注解，但仍然无法正常工作。有人可以帮我解决这个问题吗？

Customer.java

@Entity
public class Customer {

    @Id
    @GeneratedValue(strategy=GenerationType.IDENTITY)
    @Column(name = "id", nullable = false, unique = true)
    private Long id;

    private String firstName;

    private String lastName;

    protected Customer() {
    }

    public Customer(String firstName, String lastName) {
        this.firstName = firstName;
        this.lastName = lastName;
    }
        //Getters ans Setters

}

CustomerEditor.java

@Route(value = "NewPickUp", layout = MainView.class)
@SpringComponent
@UIScope
public class CustomerEditor extends VerticalLayout{

    @Autowired
    private final CustomerRepository repository;

    @Autowired
    private Customer customer;

    TextField firstName = new TextField("First name");
    TextField lastName = new TextField("Last name");
    Button save = new Button("Save", VaadinIcon.CHECK.create());

    Binder<Customer> binder = new Binder<>(Customer.class);

    @Autowired
    public CustomerEditor(CustomerRepository repository) {
        this.repository = repository;
        add(firstName, lastName, save );
        binder.forField(firstName).bind(Customer::getFirstName, Customer::setFirstName);
        binder.forField(lastName).bind(Customer::getLastName, Customer::setLastName);

        save.addClickListener(e -> save());
    }

    void save() {
        repository.save(customer);
    }
}

CustomerRepository.java

public interface CustomerRepository extends JpaRepository<Customer, Long> {

    List<Customer> findByLastNameStartsWithIgnoreCase(String lastName);
}

MainView.java

@Route
public class MainView extends AppLayout{
     public MainView() {

    Button addButton = new Button(new RouterLink("", CustomerEditor.class));
    RouterLink routerLink = new RouterLink("NewPickUp", CustomerEditor.class);
        routerLink.getElement().appendChild(addButton.getElement());
        this.addToNavbar(routerLink); 

     }

错误信息

org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'com.apt.lts.view.CustomerEditor': Unsatisfied dependency expressed through field 'customer'; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'com.apt.lts.model.Customer' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:596) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
    at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:90) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessProperties(AutowiredAnnotationBeanPostProcessor.java:374) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1411) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:592) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:515) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:305) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
    at com.vaadin.flow.spring.SpringInstantiator.getOrCreate(SpringInstantiator.java:117) ~[vaadin-spring-12.0.5.jar:na]
    at com.vaadin.flow.di.Instantiator.createRouteTarget(Instantiator.java:158) ~[flow-server-2.0.11.jar:2.0.11]
    at com.vaadin.flow.router.internal.AbstractNavigationStateRenderer.lambda$getRouteTarget(AbstractNavigationStateRenderer.java:127) ~[flow-server-2.0.11.jar:2.0.11]
    at java.base/java.util.Optional.orElseGet(Optional.java:369) ~[na:na]

Answer 1

上述错误清楚地表明您正在尝试 Autowired 一个不是 Spring 托管 bean 的 bean（此处为 Customer）。

这些 bean 以 xml 形式定义，带有标签，或带有一些特殊注释，如 @Bean, @Component, @Service, @Repository 等

简单来说，实体是您需要创建的一些 java 对象，根据您的业务逻辑自行更新和 save/update/remove 它们 in/from 数据库。它们的生命周期无法由 Spring IoC 容器管理。

Answer 2

正如 Debendra Dhinda 在他们的回答中提到的，您的 Customer class 不是 Spring 组件，因此无法注入。您可以不注入客户，而是在视图的构造函数中创建一个新客户，或者您可以在 @Configuration class 中添加一个 @Bean 定义方法。这两种方法的共同点是您在某个时候调用 new Customer()。

// code example for approach 2
@Configuration
public class MySpringConfiguration {

    // this method will be called if you inject/autowire a Customer somewhere.
    @Bean
    public Customer getCustomer(){
        return new Customer();
    }
}

使用 Spring Boot + Jpa + vaadin 保存表单数据时出现问题

Issue when saving form data using SprinBoot + Jpa + vaadin

jpa

spring-boot

vaadin-flow

Customer.java

CustomerEditor.java

CustomerRepository.java

MainView.java

错误信息