@RequestMapping(value = "/get")
 public @ResponseBody ResponseObject get(
     @RequestParam(value = "start", required = false) Integer start) {
   if (start != null) {
     return productService.getProducts(start);
   } else {
     return productService.findAll();
   }
 }
 @RequestMapping(value = "/update")
 public @ResponseBody ResponseObject update(
     @RequestBody @Valid Product product, BindingResult errors) throws Exception {
   if (errors.hasErrors())
     throw new ValidateException(errors.getAllErrors().get(0).getDefaultMessage());
   return productService.update(product);
 }
 @RequestMapping(value = "/get-dealers")
 public @ResponseBody ResponseObject getDealers(@RequestParam("productId") Integer productId)
     throws Exception {
   return productService.getDealers(productId);
 }
 @RequestMapping(value = "/find")
 public @ResponseBody ResponseObject getProduct(@RequestParam("productId") Integer productId) {
   return productService.findById(productId);
 }
 @RequestMapping(value = "/get-parts")
 public @ResponseBody ResponseObject getParts(@RequestParam("productId") Integer productId) {
   return productService.getParts(productId);
 }
 @RequestMapping(value = "/delete")
 public @ResponseBody ResponseObject deleteProduct(@RequestParam("productId") Integer productId)
     throws Exception {
   return productService.deleteById(productId);
 }