@ResponseBody
 @RequestMapping(value = "/getFolderTree", method = RequestMethod.GET)
 public Folder getFolderTree() {
   return diagramService.getFolderTree();
 }
 @ResponseBody
 @RequestMapping(value = "/deleteFolder", method = RequestMethod.POST)
 public void deleteFolder(@RequestBody OpenRequest request) {
   diagramService.deleteFolder(request.getId());
 }
 @ResponseBody
 @RequestMapping(value = "/createFolder", method = RequestMethod.POST)
 public Long createFolder(@RequestBody Folder folder) {
   return diagramService.createFolder(folder);
 }
 @ResponseBody
 @RequestMapping(value = "/updateDiagram", method = RequestMethod.POST)
 public void rewriteDiagram(@RequestBody Diagram diagram) {
   diagramService.rewriteDiagram(diagram);
 }
 @ResponseBody
 @RequestMapping(value = "/openDiagram", method = RequestMethod.POST)
 public Diagram openDiagram(@RequestBody OpenRequest request) {
   return diagramService.openDiagram(request.getId());
 }
 @ResponseBody
 @RequestMapping(value = "/saveDiagram", method = RequestMethod.POST)
 public Long saveDiagram(@RequestBody DiagramRequest diagramRequest) {
   return diagramService.saveDiagram(diagramRequest);
 }