[Spring Data Repositories] learning notes -- add a common method for repository, springrepository

[Spring Data Repositories] learning notes -- add a common method for repository, springrepository

If you want to add a method to all repository, it is not appropriate to use the method mentioned in the previous article.

For the original English version, see

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

 

1. define your own repository and inherit from the basic repository.

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

2. Defining the implementation of repository should also be inherited from the basic repository implementation.

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. Create a repository Factory

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. Use the newly created factory

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