How can I do relational database-based HTTP Session Persistence in Spring 4?

With Spring Session (it transparently will override HttpSessions from Java EE) you can just take SessionRepository interface and implement it with your custom ex. JdbcSessionRepository. It is kind of easy to do. When you have your implementation, then just add manually (you don't need @EnableRedisHttpSession annotation) created filter to filter chain, like bellow:

@Configuration
@EnableWebMvcSecurity
public class SecurityConfiguration extends WebSecurityConfigurerAdapter {

   //other stuff...

   @Autowired
   private SessionRepository<ExpiringSession> sessionRepository;

   private HttpSessionStrategy httpSessionStrategy = new CookieHttpSessionStrategy(); // or HeaderHttpSessionStrategy

   @Bean
   public SessionRepository<ExpiringSession> sessionRepository() {
       return new JdbcSessionRepository();
   }

   @Override
   protected void configure(HttpSecurity http) throws Exception {
       super.configure(http);
       SessionRepositoryFilter<ExpiringSession> sessionRepositoryFilter = new SessionRepositoryFilter<>(sessionRepository);
       sessionRepositoryFilter.setHttpSessionStrategy(httpSessionStrategy);
       http
            .addFilterBefore(sessionRepositoryFilter, ChannelProcessingFilter.class);
   }
}

Here you have how SessionRepository interface looks like. It has only 4 methods to implement. For how to create Session object, you can look in MapSessionRepository and MapSession implementation (or RedisOperationsSessionRepository and RedisSession).

public interface SessionRepository<S extends Session> {
   S createSession();
   void save(S session);
   S getSession(String id);
   void delete(String id);
}

Example solution https://github.com/Mati20041/spring-session-jpa-repository