Hibernate OGM provider for Spring configuration

Question

I created a Java application that can use SQL Server or Neo4j as a database without touching the application layer, I just modify the provider and the connection information

Answer 1

I add Java Config for Neo4j with OGM Hibernate

@Configuration
@EnableTransactionManagement
@JpaPackagesToScan(Entity.class)
public class RepositoryConfig {
    /**
     * Neo4J OGM EntityManager config
     */
    @Bean
    public LocalContainerEntityManagerFactoryBean entityManager(JpaPackagesToScanHolder holder) throws Throwable {

        Map<String, Object> properties = new HashMap<String, Object>();
        properties.put("javax.persistence.transactionType", "JTA");
        properties.put("hibernate.ogm.datastore.provider", "neo4j_embedded");
        properties.put("hibernate.ogm.datastore.database", "my-db");
        properties.put("hibernate.ogm.neo4j.database_path", "/mnt/graph.db");
        properties.put("hibernate.dialect", "org.hibernate.ogm.datastore.neo4j.Neo4jDialect");

        LocalContainerEntityManagerFactoryBean entityManager = new LocalContainerEntityManagerFactoryBean();
        entityManager.setPackagesToScan(holder.toStringArray());
        entityManager.setPersistenceUnitName("my-pu");
        entityManager.setJpaPropertyMap(properties);
        entityManager.setPersistenceProviderClass(HibernateOgmPersistence.class);
        return entityManager;
    }


    @Bean
    public PlatformTransactionManager transactionManager(EntityManagerFactory entityManagerFactory) throws Throwable {
        JpaTransactionManager transactionManager = new JpaTransactionManager();
        transactionManager.setEntityManagerFactory(entityManagerFactory);
        return transactionManager;
    }

}

And added to the pom (for Java 7 project)

    <dependency>
        <groupId>org.hibernate.ogm</groupId>
        <artifactId>hibernate-ogm-neo4j</artifactId>
        <version>4.1.0.Final</version>
    </dependency>

Answer 2

Here is the below Java configuration class(Note I'm using spring boot, you could modify according you your requirement)

@Configuration
@EnableJpaRepositories(basePackages = {
        "com.kp.swasthik.mongo.dao" }, entityManagerFactoryRef = "mongoEntityManager", transactionManagerRef = "mongoTransactionManager")
public class MongDbConfig {


    @Bean(name = "mongoEntityManager")
    public LocalContainerEntityManagerFactoryBean mongoEntityManager() throws Throwable {

        Map<String, Object> properties = new HashMap<String, Object>();
        properties.put("javax.persistence.transactionType", "resource_local");
        properties.put("hibernate.ogm.datastore.provider","mongodb");
        properties.put("hibernate.ogm.datastore.host","localhost");
        properties.put("hibernate.ogm.datastore.port","27017");
        properties.put("hibernate.ogm.datastore.database", "kpdb");
        properties.put("hibernate.ogm.datastore.create_database", "true");

        LocalContainerEntityManagerFactoryBean entityManager = new LocalContainerEntityManagerFactoryBean();
        entityManager.setPackagesToScan("com.kp.swasthik.mongo.domain");
        entityManager.setPersistenceUnitName("mongoPersistenceUnit");
        entityManager.setJpaPropertyMap(properties);
        entityManager.setPersistenceProviderClass(HibernateOgmPersistence.class);
        return entityManager;
    }

    @Bean(name = "mongoTransactionManager")
    public PlatformTransactionManager transactionManager() throws Throwable {
        JpaTransactionManager transactionManager = new JpaTransactionManager();
        transactionManager.setEntityManagerFactory(mongoEntityManager().getObject());
        return transactionManager;
    }

}

Regarding your Second question on @NodeEntity @GraphId etc. Similar to hibernate OGM sprig provides jpa implementation for no sql using spring-data for number of nosql datastores such as redis, mongodb,cassandra, hbase, couchdb, solr, elasticsearch etc. @NodeEnity and @GraphId is used in neo4j