Spring Data JPA @EnableJpaRepositories配置詳解

@EnableJpaRepositories注解用於Srping JPA的代碼配置，用於取代xml形式的配置文件，@EnableJpaRepositories支持的配置形式豐富多用，本篇文章詳細講解。

1、簡單配置

1 @EnableJpaRepositories("com.spr.repository")

簡單配置支持多個package，格式如下：

1 @EnableJpaRepositories({"com.cshtong.sample.repository", "com.cshtong.tower.repository"})

 

2、單值和多組值配置方式

大部分注解可以都支持單個注解方式和多個注解，多個注解通常采用"{}"符號包含的一組數據。

比如：字符串形式的  "x.y.z"  =>  {"x.y.z","a.b.c"}

類別： A.class => {A.class, B.class}

 

3、完整的@EnableJpaRepositories注解

 1 @EnableJpaRepositories(
 2     basePackages = {},
 3     basePackageClasses = {},
 4     includeFilters = {},
 5     excludeFilters = {},
 6     repositoryImplementationPostfix = "Impl",
 7     namedQueriesLocation = "",//META-INF/jpa-named-queries.properties
 8     queryLookupStrategy=QueryLookupStrategy.Key.CREATE_IF_NOT_FOUND, //QueryLookupStrategy.Key.x
 9     repositoryFactoryBeanClass=JpaRepositoryFactoryBean.class, //class
10     entityManagerFactoryRef="entityManagerFactory",
11     transactionManagerRef="transactionManager",
12     considerNestedRepositories=false, 
13     enableDefaultTransactions=true
14 )

下面分別解釋各個配置項的作用

1）basePackage

用於配置掃描Repositories所在的package及子package。簡單配置中的配置則等同於此項配置值，basePackages可以配置為單個字符串，也可以配置為字符串數組形式。

1 @EnableJpaRepositories(
2         basePackages = "com.cshtong")

多個包路徑

1 @EnableJpaRepositories(
2         basePackages = {"com.cshtong.sample.repository", "com.cshtong.tower.repository"})

 

2）basePackageClasses

指定 Repository 類

1 @EnableJpaRepositories(basePackageClasses = BookRepository.class)

1 @EnableJpaRepositories(
2         basePackageClasses = {ShopRepository.class, OrganizationRepository.class})

備注：測試的時候發現，配置包類的一個Repositories類，該包內其他Repositores也會被加載？？？

3）includeFilters

過濾器，該過濾區采用ComponentScan的過濾器類

1 @EnableJpaRepositories(
2         includeFilters={@ComponentScan.Filter(type=FilterType.ANNOTATION, value=Repository.class)})

 

4）excludeFilters

不包含過濾器

1 @EnableJpaRepositories(
2         excludeFilters={
3                 @ComponentScan.Filter(type=FilterType.ANNOTATION, value=Service.class),
4                 @ComponentScan.Filter(type=FilterType.ANNOTATION, value=Controller.class)})

 

5）repositoryImplementationPostfix

實現類追加的尾部，比如ShopRepository，對應的為ShopRepositoryImpl

6）namedQueriesLocation

named SQL存放的位置，默認為META-INF/jpa-named-queries.properties

7）queryLookupStrategy

構建條件查詢的策略，包含三種方式CREATE，USE_DECLARED_QUERY，CREATE_IF_NOT_FOUND

• CREATE：按照接口名稱自動構建查詢
• USE_DECLARED_QUERY：用戶聲明查詢
• CREATE_IF_NOT_FOUND：先搜索用戶聲明的，不存在則自動構建

該策略針對如下通過接口名稱自動生成查詢的場景

  List<Person> findByEmailAddressAndLastname(EmailAddress emailAddress, String lastname);

  // Enables the distinct flag for the query
  List<Person> findDistinctPeopleByLastnameOrFirstname(String lastname, String firstname);
  List<Person> findPeopleDistinctByLastnameOrFirstname(String lastname, String firstname);

  // Enabling ignoring case for an individual property
  List<Person> findByLastnameIgnoreCase(String lastname);
  // Enabling ignoring case for all suitable properties
  List<Person> findByLastnameAndFirstnameAllIgnoreCase(String lastname, String firstname);

  // Enabling static ORDER BY for a query
  List<Person> findByLastnameOrderByFirstnameAsc(String lastname);
  List<Person> findByLastnameOrderByFirstnameDesc(String lastname)

8）repositoryFactoryBeanClass

指定Repository的工廠類

9)entityManagerFactoryRef

實體管理工廠引用名稱，對應到@Bean注解對應的方法

 1     @Bean
 2     public LocalContainerEntityManagerFactoryBean entityManagerFactory() {
 3         LocalContainerEntityManagerFactoryBean entityManagerFactoryBean = new LocalContainerEntityManagerFactoryBean();
 4         entityManagerFactoryBean.setDataSource(dataSource());
 5         entityManagerFactoryBean.setPersistenceProviderClass(HibernatePersistenceProvider.class);
 6         entityManagerFactoryBean
 7                 .setPackagesToScan(env.getRequiredProperty(PROPERTY_NAME_ENTITYMANAGER_PACKAGES_TO_SCAN));
 8         entityManagerFactoryBean.setJpaProperties(hibProperties());
 9         return entityManagerFactoryBean;
10     }

 

10)transactionManagerRef

事務管理工廠引用名稱，對應到@Bean注解對應的方法

1 2 3 4 5 6

@Bean public  JpaTransactionManager transactionManager() {      JpaTransactionManager transactionManager =  new  JpaTransactionManager();      transactionManager.setEntityManagerFactory(entityManagerFactory().getObject());      return  transactionManager; }