@Entity
@Table(name = "company")
public class Company implements Serializable {
 
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Integer id;
 
    @Column
    private String name;
 
    @OneToMany(mappedBy = "company")
    @LazyCollection(LazyCollectionOption.FALSE)
    private Collection<Employee> employees;

@Entity
@Table(name = "company")
public class Company implements Serializable {

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Integer id;

    @Column
    private String name;

    @OneToMany(mappedBy = "company", cascade = CascadeType.ALL)
    @LazyCollection(LazyCollectionOption.FALSE)
    private Collection<Employee> employees;

@Controller
@RequestMapping("/company")
public class CompanyController {
 
    @Autowired
    CompanyRepository companyRepository;
 
    @RequestMapping(value = "/{id}",
                    method = RequestMethod.GET,
                    produces = "application/json")
    @ResponseBody public Company getCompany(@PathVariable("id") Integer id) {
        return companyRepository.getCompany(id);
    }
 
    @RequestMapping(method = RequestMethod.PUT,
                    consumes = "application/json",
                    headers = "content-type=application/json")
    public String updateCompany(@RequestBody Company company) {
        companyRepository.updateCompany(company);
        return "redirect:/company/" + company.getId();
    }
}

@Repository
@Transactional(propagation = Propagation.REQUIRED)
public class HibernateCompanyRepository implements CompanyRepository {
 
    @Autowired
    HibernateTemplate template;
 
    // др. методы не пропущены
 
    @Override
    public void updateCompany(Company company) {
        template.update(company);
    }
}

{
  "name" : "IBM",
  "employees" : [
    {
      "name" : "John",
      "id" : 2
    },
    {
      "name" : "Bill",
      "id" : 4
    }
  ],
  "id" : 2
}

{
  "name" : "IBM",
  "employees" : [
    {
      "name" : "John",
      "id" : 2
    }
  ],
  "id" : 2
}