@RequestMapping(value = "/edit/{id}", method = RequestMethod.GET)
  public String edit(@PathVariable Long id, ModelMap model, RedirectAttributes redirectAttributes) {
    ComputerAndCompanies computerAndCompanies = computerService.findWithAllCompanies(id);
    if (computerAndCompanies == null) {
      redirectAttributes.addFlashAttribute("error", "Computer not found");

      return "redirect:/computers";
    } else {
      model.addAttribute("form", new ComputerForm(computerAndCompanies.getComputer()));
      model.addAttribute("companies", computerAndCompanies.getCompanies());

      return "/edit";
    }
  }