spring roo pattern vs repository pattern

Question

我正在使用spring roo进行我的一个项目。 spring roo的作用是为现有类添加持久性方法。例如，您可以调用Person.persist（）来保存数据库中person类型的对象。

我最近看到了另一种模式。以下是代码。

@Entity
public class Customer {

    @Id
    @GeneratedValue(strategy=GenerationType.AUTO)
    private int id;
    private String firstName;
    private String lastName;

    protected Customer() {}

    public Customer(String firstName, String lastName) {
        this.firstName = firstName;
        this.lastName = lastName;
    }

}

@Repository
public class CustomerRepository {
    @PersistenceContext
    private EntityManager em;

    @Transactional
    public void save(Customer c) {
        em.persist(c);
    }
}

@Controller
public class HomeController {

    @Autowired
    CustomerRepository customerRepository;

    private static final Logger logger = LoggerFactory.getLogger(HomeController.class);

    /**
     * Simply selects the home view to render by returning its name.
     * @throws Exception 
     */
    @Transactional
    @RequestMapping(value = "/", method = RequestMethod.GET)
    public String home(Locale locale, Model model) {
        logger.info("Welcome home controller! The client locale is {}.", locale);
        Customer c = new Customer("XXX", "YYY");
        customerRepository.save(c);
        return "home";
    }
}

每种方法的优点和缺点是什么？