Jpa Repository

Interface JpaRepository

package org.springframework.data.jpa.repository;

import java.util.List;

import javax.persistence.EntityManager;

import org.springframework.data.domain.Example;
import org.springframework.data.domain.Sort;
import org.springframework.data.repository.NoRepositoryBean;
import org.springframework.data.repository.PagingAndSortingRepository;
import org.springframework.data.repository.query.QueryByExampleExecutor;

/**
 * JPA specific extension of {@link org.springframework.data.repository.Repository}.
 *
 * @author Oliver Gierke
 * @author Christoph Strobl
 * @author Mark Paluch
 */
@NoRepositoryBean
public interface JpaRepository<T, ID> extends PagingAndSortingRepository<T, ID>, QueryByExampleExecutor<T> {

    /*
     * (non-Javadoc)
     * @see org.springframework.data.repository.CrudRepository#findAll()
     */
    List<T> findAll();

    /*
     * (non-Javadoc)
     * @see org.springframework.data.repository.PagingAndSortingRepository#findAll(org.springframework.data.domain.Sort)
     */
    List<T> findAll(Sort sort);

    /*
     * (non-Javadoc)
     * @see org.springframework.data.repository.CrudRepository#findAll(java.lang.Iterable)
     */
    List<T> findAllById(Iterable<ID> ids);

    /*
     * (non-Javadoc)
     * @see org.springframework.data.repository.CrudRepository#save(java.lang.Iterable)
     */
    <S extends T> List<S> saveAll(Iterable<S> entities);

    /**
     * Flushes all pending changes to the database.
     */
    void flush();

    /**
     * Saves an entity and flushes changes instantly.
     *
     * @param entity
     * @return the saved entity
     */
    <S extends T> S saveAndFlush(S entity);

    /**
     * Deletes the given entities in a batch which means it will create a single {@link Query}. Assume that we will clear
     * the {@link javax.persistence.EntityManager} after the call.
     *
     * @param entities
     */
    void deleteInBatch(Iterable<T> entities);

    /**
     * Deletes all entities in a batch call.
     */
    void deleteAllInBatch();

    /**
     * Returns a reference to the entity with the given identifier.
     *
     * @param id must not be {@literal null}.
     * @return a reference to the entity with the given identifier.
     * @see EntityManager#getReference(Class, Object)
     * @throws javax.persistence.EntityNotFoundException if no entity exists for given {@code id}.
     */
    T getOne(ID id);

    /*
     * (non-Javadoc)
     * @see org.springframework.data.repository.query.QueryByExampleExecutor#findAll(org.springframework.data.domain.Example)
     */
    @Override
    <S extends T> List<S> findAll(Example<S> example);

    /*
     * (non-Javadoc)
     * @see org.springframework.data.repository.query.QueryByExampleExecutor#findAll(org.springframework.data.domain.Example, org.springframework.data.domain.Sort)
     */
    @Override
    <S extends T> List<S> findAll(Example<S> example, Sort sort);
}

Exemple de création d'un Repository

// Création d'une interface (sans annotation) qui étend JpaRepository
// Cette interface sera directement "injectable" sans aucune implémentation (@Autowired)
// JpaRepository<ENTITE,TYPE CLE PRIMAIRE>
public interface PersonRepository extends JpaRepository<Person, Long> {
}

Exemple d'utilisation d'un Repository dans un service

@Component
public PersonApp {
    @Autowired PersonRepository pRepo;

    public List<Person> list() {
        return pRepo.findAll();
    }

    public void save(Person p) {
        pRepo.save(p);
    }
}