Spring JPA hibernate 自动装配依赖项注入失败

Question

仍在尝试了解 Spring 中的所有内容是如何组合在一起的，但我又碰壁了。

Application.java

@PropertySource("classpath:application.properties")
@ComponentScan
@EnableAutoConfiguration
@Configuration
@EnableWebMvc
@EnableJpaRepositories(basePackageClasses = {QuestionRepository.class})
public class Application extends SpringBootServletInitializer {

    @Override
    protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
        return application.sources(Application.class);
    }


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

TestController.java

@Controller
public class TestController {
 
 @Autowired
 public QuestionRepository questionRepository;
 
    @RequestMapping("/")
    public String welcome(Map<String, Object> model) {
        return "test";
    }

}

QuestionRepository.java

@Repository
public interface QuestionRepository extends CrudRepository<Question, Long>{

 //findBy methhods are special with spring/jpa 
 public Collection<Question> findByName(String title);
 
 public long count();
 
}

Question.java

@Entity
@Table(name="questions")
public class Question {
 
 @Column(name="questionText")
 private String questionText;
 
 @Column(name="answerText")
 private String answerText;
 
 @Column(name="owningDeck")
 private String owningDeck;
 
 @Id
    @Column(name = "id")
    @GeneratedValue(strategy = GenerationType.AUTO)
 private int id;
 
 
 public Question() {
 }
 
 
 public void setQuestion(String q, int id) {
  this.questionText = q;
 }
 
 
}

annnd 显示注入失败的错误跟踪

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'testController': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: public repo.QuestionRepository hello.TestController.questionRepository; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'questionRepository': Cannot create inner bean '(inner bean)#59f4e49e' of type [org.springframework.orm.jpa.SharedEntityManagerCreator] while setting bean property 'entityManager'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name '(inner bean)#59f4e49e': Cannot resolve reference to bean 'entityManagerFactory' while setting constructor argument; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'entityManagerFactory' is defined
 at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:293)
 at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1186)
 at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:537)
 at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:475)
 at org.springframework.beans.factory.support.AbstractBeanFactory.getObject(AbstractBeanFactory.java:302)
 at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:228)
 at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:298)
 at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:193)
 at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:706)
 at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:762)
 at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:482)
 at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.refresh(EmbeddedWebApplicationContext.java:124)
 at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:609)
 at org.springframework.boot.SpringApplication.run(SpringApplication.java:321)
 at org.springframework.boot.SpringApplication.run(SpringApplication.java:806)
 at org.springframework.boot.SpringApplication.run(SpringApplication.java:795)
 at hello.Application.main(Application.java:36)
Caused by: org.springframework.beans.factory.BeanCreationException: Could not autowire field: public repo.QuestionRepository hello.TestController.questionRepository; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'questionRepository': Cannot create inner bean '(inner bean)#59f4e49e' of type [org.springframework.orm.jpa.SharedEntityManagerCreator] while setting bean property 'entityManager'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name '(inner bean)#59f4e49e': Cannot resolve reference to bean 'entityManagerFactory' while setting constructor argument; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'entityManagerFactory' is defined
 at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:509)
 at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:87)
 at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:290)
 ... 16 common frames omitted
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'questionRepository': Cannot create inner bean '(inner bean)#59f4e49e' of type [org.springframework.orm.jpa.SharedEntityManagerCreator] while setting bean property 'entityManager'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name '(inner bean)#59f4e49e': Cannot resolve reference to bean 'entityManagerFactory' while setting constructor argument; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'entityManagerFactory' is defined
 at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveInnerBean(BeanDefinitionValueResolver.java:290)
 at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveValueIfNecessary(BeanDefinitionValueResolver.java:129)
 at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1457)
 at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1198)
 at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:537)
 at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:475)
 at org.springframework.beans.factory.support.AbstractBeanFactory.getObject(AbstractBeanFactory.java:302)
 at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:228)
 at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:298)
 at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:193)
 at org.springframework.beans.factory.support.DefaultListableBeanFactory.findAutowireCandidates(DefaultListableBeanFactory.java:1021)
 at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:964)
 at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:862)
 at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:481)
 ... 18 common frames omitted
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name '(inner bean)#59f4e49e': Cannot resolve reference to bean 'entityManagerFactory' while setting constructor argument; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'entityManagerFactory' is defined
 at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveReference(BeanDefinitionValueResolver.java:336)
 at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveValueIfNecessary(BeanDefinitionValueResolver.java:108)
 at org.springframework.beans.factory.support.ConstructorResolver.resolveConstructorArguments(ConstructorResolver.java:632)
 at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:442)
 at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1095)
 at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:990)
 at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:504)
 at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:475)
 at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveInnerBean(BeanDefinitionValueResolver.java:276)
 ... 31 common frames omitted
Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'entityManagerFactory' is defined
 at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBeanDefinition(DefaultListableBeanFactory.java:641)
 at org.springframework.beans.factory.support.AbstractBeanFactory.getMergedLocalBeanDefinition(AbstractBeanFactory.java:1157)
 at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:280)
 at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:193)
 at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveReference(BeanDefinitionValueResolver.java:328)
 ... 39 common frames omitted

知道为什么我无法从我的控制器自动连接 QuestionRepository 吗？

----在application.properties文件中编辑-----

application.properties

spring.view.prefix: /WEB-INF/jsp/
spring.view.suffix: .jsp
spring.datasource.url=jdbc:mysql://localhost/
spring.datasource.username=dbuser
spring.datasource.password=dbpass
spring.datasource.driverClassName=com.mysql.jdbc.Driver
hibernate.dialect=org.hibernate.dialect.MySQLDialect
jpa.database=MYSQL

Answer 1

您遇到的异常与 Persistence Provider（或数据库）的设置方式有关。您是否创建了 persistence.xml 文件并将所有数据库设置包含在其中？

对您的代码进行的另一项小修正无法解决您在此处发布的问题，但您已指定问题 class 的 ID 如下：

private int id;

您需要将其更新为：

private Long id;

如您在 QuestionRepository 中指定的那样 class Key 或 Id 字段的类型为 Long。

Spring JPA hibernate 自动装配依赖项注入失败

Spring JPA hibernate Injection of autowired dependencies failed

spring

hibernate

jpa

dependency-injection