BaseRepositoryFactoryBean.java

package net.petrikainulainen.springdata.jpa.common;

import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.data.jpa.repository.support.JpaRepositoryFactory;
import org.springframework.data.jpa.repository.support.JpaRepositoryFactoryBean;
import org.springframework.data.repository.core.RepositoryMetadata;
import org.springframework.data.repository.core.support.RepositoryFactorySupport;

import javax.persistence.EntityManager;
import java.io.Serializable;

/**
 * This factory bean replaces the default implementation of our repository interfaces
 * with the {@link BaseRepositoryImpl}. This ensures that the {@link BaseRepository#deleteById(Serializable)}
 * method is added into all Spring Data JPA repositories of our example application.
 *
 * @author Petri Kainulainen
 */
public class BaseRepositoryFactoryBean<R extends JpaRepository<T, I>, T,
        I extends Serializable> extends JpaRepositoryFactoryBean<R, T, I> {

    @Override
    protected RepositoryFactorySupport createRepositoryFactory(EntityManager em) {
        return new BaseRepositoryFactory(em);
    }

    private static class BaseRepositoryFactory<T, I extends Serializable>
            extends JpaRepositoryFactory {

        private final EntityManager em;

        public BaseRepositoryFactory(EntityManager em) {
            super(em);
            this.em = em;
        }

        @Override
        protected Object getTargetRepository(RepositoryMetadata metadata) {
            return new BaseRepositoryImpl<T, I>((Class<T>) metadata.getDomainType(), em);
        }

        @Override
        protected Class<?> getRepositoryBaseClass(RepositoryMetadata metadata) {
            return BaseRepositoryImpl.class;
        }
    }
}