@OneToMany(fetch = FetchType.LAZY)
    private List<Contact> contact = new ArrayList<>();

    @Bean
    public PlatformTransactionManager transactionManager() throws NamingException {
        return new JpaTransactionManager(emf().getObject());
    }

@EnableJpaRepositories(basePackages = "com.opalev", entityManagerFactoryRef = "emf", transactionManagerRef = "transactionManager")

    @Override
    public void extendMessageConverters(List<HttpMessageConverter<?>> converters) {
        for (HttpMessageConverter converter : converters) {
            if (converter instanceof org.springframework.http.converter.json.MappingJackson2HttpMessageConverter) {
                ObjectMapper mapper = ((MappingJackson2HttpMessageConverter) converter).getObjectMapper();
                Hibernate5Module hm = new Hibernate5Module();
              hm.disable(Hibernate5Module.Feature.USE_TRANSIENT_ANNOTATION);
                mapper.registerModule(hm);
                // replace Hibernate5Module() with the proper class for your hibernate version.
            }
        }
    }

    @RequestMapping(value = "/updateUserName", method = RequestMethod.GET)
    @ResponseBody
    public List<User> updateUserName(@RequestParam(value = "id", required = false) Integer userId, @RequestParam(value = "name", required = false) String newName) {
        userList.clear();
        User user = userRepository.findById(userId).get();
        if (newName != null && !"".equalsIgnoreCase(newName)) {
            user.setName(newName);
            userRepository.save(user);
        }
        userList.add(user);
        return userList;
    }