Hibernate naming strategy per entity

Question

I have one global naming strategy but for a few entities I want to use a different one. Is it possible in jpa or hibernate?

clarification: i don't want to use @Table(name="xxx") nor @Column(name="xxx"). i'm asking about naming strategy component (described for example here: Hibernate naming strategy). that's a component that infer the column and table names for you

Answer 1

I don't see a way in the Hibernate source code. The EntityBinder is coming up with names using ObjectNameNormalizer.NamingStrategyHelper, which gets the naming strategy from either Configuration.namingStrategy (the global one) or from a complex path which goes through MetadataImpl and lands nowhere (no usages).

So you're likely stuck with overriding field names manually. I don't even see an obvious way to get context about the field, so I think even a split-brain naming strategy looks like it's out of the question.

Update: After seeing @anthony-accioly's answer, I thought I that last sentence may have been wrong. So I tested it as follows

package internal.sandbox.domain;

@Entity
public class SomeEntity {

    private String id;
    private String someField;

    @Id
    public String getId() {
        return id;
    }

    public void setId(String id) {
        this.id = id;
    }

    public String getSomeField() {
        return someField;
    }

    public void setSomeField(String someField) {
        this.someField = someField;
    }
}

with a JpaConfiguration as follows

@Configuration
@EnableTransactionManagement
@EnableJpaRepositories("internal.sandbox.dao")
@Import(DataSourceConfiguration.class)
public class JpaConfiguration {

    @Bean
    @Autowired
    public LocalContainerEntityManagerFactoryBean localContainerEntityManagerFactoryBean(DataSource dataSource) {

        HibernateJpaVendorAdapter vendorAdapter = new HibernateJpaVendorAdapter();
        vendorAdapter.setDatabasePlatform("org.hibernate.dialect.PostgreSQL82Dialect");
        vendorAdapter.setDatabase(Database.POSTGRESQL);

        LocalContainerEntityManagerFactoryBean factory = new LocalContainerEntityManagerFactoryBean();
        factory.setJpaVendorAdapter(vendorAdapter);
        factory.setPackagesToScan("internal.sandbox"); // note, no ".domain"
        factory.setDataSource(dataSource);

        Properties properties = new Properties();
        properties.setProperty("hibernate.cache.use_second_level_cache", "false");
        properties.setProperty("hibernate.ejb.naming_strategy", "org.hibernate.cfg.ImprovedNamingStrategy");

        factory.setJpaProperties(properties);

        return factory;
    }
    ...

a Spring Data DAO as follows

public interface SomeEntityDao extends CrudRepository<SomeEntity, String> {
}

and an integration test as follows

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(classes = {ApplicationConfiguration.class, JpaConfiguration.class})
public class SomeEntityDaoIntegrationTests {

    @Autowired
    private SomeEntityDao someEntityDao;

    @Test
    public void testSave() {

        SomeEntity someEntity = new SomeEntity();
        someEntity.setId("foo");
        someEntity.setSomeField("bar");

        this.someEntityDao.save(someEntity);
    }
}

I put breakpoints in the ImprovedNamingStrategy, and classToTableName() was called with "SomeEntity" and propertyToColumnName() was called with "someField".

In other words, package information isn't being passed in, so at least in this setup, it can't be used to apply a different naming strategy based on package name.