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[Spring Data Repositories]学习笔记--为repository添加通用的方法

如果想把一个方法加到所有的repository中,用前一篇提到的方法就不合适了。

英文原版,请看

http://docs.spring.io/spring-data/data-mongo/docs/1.5.2.RELEASE/reference/html/repositories.html#repositories.custom-behaviour-for-all-repositories

 

1. 定义自己的repository,要从基础的repository进行继承。

public interface MyRepository<T, ID extends Serializable> extends JpaRepository<T,ID> {void sharedCustomMethod(ID id);}

2. 定义repository的实现,也要从基础的repository实现进行继承。

public class MyRepositoryImpl<T,ID extends Serializable> extends SimpleJpaRepository<T,ID> Implements MyRepository<T,ID> {private EntityManager entityManager;public MyRepositoryImpl(Class<T> domainClass, EntityManager entityManager){super(domainClass,entityManager);this.entityManager = entityManager;}public void sharedCustomMethod(ID id){//implementation goes here}}

3. 创建一个repository工厂

public class MyRepositoryFactoryBean<R extends JpaRepository<T, I>, T, I extends Serializable>  extends JpaRepositoryFactoryBean<R, T, I> {  protected RepositoryFactorySupport createRepositoryFactory(EntityManager entityManager) {    return new MyRepositoryFactory(entityManager);  }  private static class MyRepositoryFactory<T, I extends Serializable> extends JpaRepositoryFactory {    private EntityManager entityManager;    public MyRepositoryFactory(EntityManager entityManager) {      super(entityManager);      this.entityManager = entityManager;    }    protected Object getTargetRepository(RepositoryMetadata metadata) {      return new MyRepositoryImpl<T, I>((Class<T>) metadata.getDomainClass(), entityManager);    }    protected Class<?> getRepositoryBaseClass(RepositoryMetadata metadata) {      // The RepositoryMetadata can be safely ignored, it is used by the JpaRepositoryFactory      //to check for QueryDslJpaRepository‘s which is out of scope.      return MyRepository.class;    }  }}

4. 使用新创建的factory

<repositories base-package="com.acme.repository" factory-class="com.acme.MyRepositoryFactoryBean"/>