将休眠命名策略设置为 Spring bean答案

【问题标题】：Set hibernate naming strategy as Spring bean将休眠命名策略设置为 Spring bean
【发布时间】：2015-08-05 10:06:21
【问题描述】：

我有一个带有 Hibernate 的 spring-boot 应用程序。我想提供自定义 NamingStrategy 来为 hibernate 管理的每个表添加前缀。

我发现我可以使用属性：

spring.jpa.hibernate.naming_strategy=com.whatever.MyNamingStrategy

这很好用，除了我想根据属性动态地添加前缀。我的目标是：

@Component
public class PrefixNamingStrategy extends DefaultNamingStrategy {

    private final String prefix;

    @Autowired
    public PrefixNamingStrategy(@Value("db.table.prefix") String prefix) {
        this.prefix = prefix;
    }

    @Override
    public String tableName(String tableName) {
        return prefix + super.tableName(tableName);
    }
}

显然这不适用于该属性。

我尝试提供自定义 SessionFactory 并在那里提供 NamingStrategy 但没有运气 - bean 是在 hibernate 初始化后创建的，甚至似乎没有被使用：

@Autowired
@Bean(name = "sessionFactory")
public SessionFactory getSessionFactory(DataSource dataSource) {

    LocalSessionFactoryBuilder sessionBuilder = new LocalSessionFactoryBuilder(dataSource);

    sessionBuilder.setNamingStrategy(...); // !

    return sessionBuilder.buildSessionFactory();
}

有没有办法将自定义NamingStrategy 提供为 bean？

干杯

【问题讨论】：

标签： spring hibernate spring-boot

【解决方案1】：

知道这不太理想，我最终通过VendorAdapter：

命名策略委托器（注意NamingStrategy已被弃用）：

@Component
public class PrefixNamingStrategyDelegator extends ImprovedNamingStrategyDelegator {

@Autowired
public PrefixNamingStrategyDelegator(final @Value("${application.environment}_") String prefix) {
    super(
            new HbmNamingStrategyDelegate() {
                @Override
                public String toPhysicalTableName(String tableName) {
                    return prefix + super.toPhysicalTableName(tableName);
                }
            },
            new JpaNamingStrategyDelegate() {
                @Override
                public String toPhysicalTableName(String tableName) {
                    return prefix + super.toPhysicalTableName(tableName);
                }
            }
    );
}

@Override
public NamingStrategyDelegate getNamingStrategyDelegate(boolean isHbm) {
    return super.getNamingStrategyDelegate(isHbm);
}
}

JpaPersistenceProvider 将NamingStrategyDelegator 偷偷溜进去：

@Component
/**
 * See {@link org.springframework.orm.jpa.vendor.SpringHibernateJpaPersistenceProvider}
 *
 * We can't subclass that class but still need to sneak {@link org.hibernate.cfg.naming.NamingStrategyDelegator} into it.
 */
public class SpringHibernateJpaPersistenceProviderWithNamingStrategy extends HibernatePersistenceProvider {

private final NamingStrategyDelegator namingStrategy;

@Autowired
public SpringHibernateJpaPersistenceProviderWithNamingStrategy(NamingStrategyDelegator namingStrategy) {
    this.namingStrategy = namingStrategy;
}

@Override
public EntityManagerFactory createContainerEntityManagerFactory(final PersistenceUnitInfo info, Map properties) {
    return new EntityManagerFactoryBuilderImpl(new PersistenceUnitInfoDescriptor(info), properties) {
        @Override
        public Configuration buildHibernateConfiguration(ServiceRegistry serviceRegistry) {
            Configuration configuration = super.buildHibernateConfiguration(serviceRegistry);
            if (info instanceof SmartPersistenceUnitInfo) {
                for (String managedPackage : ((SmartPersistenceUnitInfo) info).getManagedPackages()) {
                    configuration.addPackage(managedPackage);
                }
            }

            configuration.setNamingStrategyDelegator(namingStrategy);

            return configuration;
        }
    }.build();
}
}

在我的@Configuration：

@Bean
public AbstractJpaVendorAdapter customJPAVendorAdapter(HibernatePersistenceProvider jpaPersistenceProvider) {
    return new HibernateJpaVendorAdapter() {
        @Override
        public PersistenceProvider getPersistenceProvider() {
            return jpaPersistenceProvider;
        }
    };
}

PersistenceProvider 本身是 SpringHibernateJpaPersistenceProvider 的原始副本（它的包是私有的，不能被子分类），并添加了一行：

configuration.setNamingStrategyDelegator(namingStrategy);

有效。但丑得像...（你知道）

【讨论】：