如何在Spring JPA中注入CrudRepository？

Question

我想使用spring-data-jpa和CrudRepository<T, ID extends Serializable> 。 但我不能讓它自動裝配。 （同一個包中的所有其他服務都正確連接）：

@Service
public class UserService {
    @Resource
    private UserRepo repo;

    //this does neither work
    //@Autowired
    //private CrudRepository<User, Long> repo;

}

public interface UserRepo extends CrudRepository<User, Long> {

}

@Entity
public class User {
    @Id
    private Long id;
} 

結果：

引起：org.springframework.beans.factory.BeanCreationException：創建名為'userService'的bean時出錯：資源依賴注入失敗; 嵌套異常是org.springframework.beans.factory.NoSuchBeanDefinitionException：沒有為依賴項找到[UserRepo]類型的限定bean：期望至少有一個bean符合此依賴關系的autowire候選資格。 依賴注釋：{@ javax.annotation.Resource（shareable = true，mappedName =，description =，name =，type = class java.lang.Object，lookup =，authenticationType = CONTAINER）}

這可能有什么問題？

從文檔我認為它應該工作而不編寫實現：

在典型的Java應用程序中，您希望編寫一個實現CustomerRepository的類。 但這就是使Spring Data JPA如此強大的原因：您不必編寫存儲庫接口的實現。 Spring Data JPA在您運行應用程序時動態創建實現。

---

更新了SpringConfig：

@Configuration
@EnableTransactionManagement
@EnableJpaRepositories("my.package")
public class AppConfig {

    @Bean
    public LocalContainerEntityManagerFactoryBean emf() throws ClassNotFoundException, PropertyVetoException {
        LocalContainerEntityManagerFactoryBean emf = new LocalContainerEntityManagerFactoryBean();
        emf.setDataSource(dataSource());
        emf.setPackagesToScan("my.package");
        emf.setJpaVendorAdapter(jpaAdapter());
        emf.setJpaProperties(jpaProterties());
        return emf;
    }
}

結果：emf丟失了，這很奇怪，因為我已經有了工作DAO服務，我可以毫無問題地自動裝配EntityManager和EMF 。

Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name '(inner bean)#1a6e658': 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:1094)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:989)
    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)
    ... 50 more
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:1159)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:282)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:195)
    at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveReference(BeanDefinitionValueResolver.java:328)
    ... 58 more

Answer 1

您應該驗證以下內容：

1）將注解UserRepo與@Repository 。

2）你的spring bean xml文件應包含在其中：

<jpa:repositories base-package="your.repository.package"></jpa:repositories>

3）我建議用@Autowired而不是@Resource注入這種類型的bean

UPDATE

看來你做了我的前三步，現在你已經領先一步了。 現在，請記住，在Java的配置方法的名字做的事。 將emf()更改為entityManagerFactory() （更“標准”），或將entity-manager-factory-ref為emf 。 例：

@Bean
    public LocalContainerEntityManagerFactoryBean entityManagerFactory() throws ClassNotFoundException, PropertyVetoException {
        LocalContainerEntityManagerFactoryBean emf = new LocalContainerEntityManagerFactoryBean();
        emf.setDataSource(dataSource());
        emf.setPackagesToScan("my.package");
        emf.setJpaVendorAdapter(jpaAdapter());
        emf.setJpaProperties(jpaProterties());
        return emf;
    }

Answer 2

UserRepo不需要注釋：

 @Repository

Answer 3

它必須是applicationContext配置中的問題。 這是我過去使用它的那個：

<jpa:repositories
    base-package="package.containing.your.repositories"
    factory-class="org.springframework.data.jpa.repository.support.JpaRepositoryFactoryBean"
    transaction-manager-ref="transactionManager"
    entity-manager-factory-ref="entityManagerFactory" />

<bean
    id="transactionManager"
    class="org.springframework.orm.jpa.JpaTransactionManager"
    p:entityManagerFactory-ref="entityManagerFactory" />

<bean
    id="hibernateJpaVendorAdapter"
    class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter" />

<bean
    id="entityManagerFactory"
    class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean"
    p:dataSource-ref="dataSource"
    p:persistenceUnitName="PU"
    p:jpaVendorAdapter-ref="hibernateJpaVendorAdapter"
    p:jpaProperties="classpath:hibernate.properties" />

<util:property-path id="sessionFactory" path="entityManagerFactory.sessionFactory" />

Answer 4

使用XML和注釋配置spring數據JPA

//This is the two way to configure spring data JPA
    @EnableJpaRepositories (basePackages= "Repository Bean is located in package", entityManagerFactoryRef= "Here is your configuration of EntityManagerFactoryBean")

    <jpa:repositories base-package= "Repository Bean where package"
    Entity-manager-factory-ref= "Here is your configured EntityManagerFactoryBean" ></jpa:repositories>
   // Sample code：
   @Configuration
   @EnableTransactionManagement
   @EnableJpaRepositories(basePackages="com.zxg.springdata", 
                  entityManagerFactoryRef="factoryBean")
  public class SpringDataConfig {
    @Bean
    public LocalContainerEntityManagerFactoryBean factoryBean (
      ComboPooledDataSource dataSource, JpaVendorAdapter jpaVendorAdapter
      ){
         LocalContainerEntityManagerFactoryBean factoryBean = new 
                LocalContainerEntityManagerFactoryBean ();
         FactoryBean.setDataSource (dataSource);
         FactoryBean.setJpaVendorAdapter (jpaVendorAdapter);
         FactoryBean.setPackagesToScan ("com.zxg.springdata");
         Return factoryBean;
       }
    }