@ResponseBody
 @RequestMapping(value = "/deleteFolder", method = RequestMethod.POST)
 public void deleteFolder(@RequestBody OpenRequest request) {
   diagramService.deleteFolder(request.getId());
 }
 @ResponseBody
 @RequestMapping(value = "/openDiagram", method = RequestMethod.POST)
 public Diagram openDiagram(@RequestBody OpenRequest request) {
   return diagramService.openDiagram(request.getId());
 }