@RestController
public class FolderController {

    private final FolderService service;

    public RequestController(FolderService service) {
        this.service = service;
    }
    /**
     *
     * @return list of all folders at "/" endpoint at GET request
     * @throws IOException
     */
    @RequestMapping(name="/", method = GET)
    public JsonNode returnFoldersList() throws IOException {
        return service.getAll();
    }

    /**
     * komentarze nad metodami, do kodu lepiej pisać takim komentarzem.
     * Intellij generuje to automatycznie jeżeli wpiszesz: /** i naciśniesz enter
     * @param folder data by ID at "/{folderId}" endpoint at GET request
     * @return
     */
    @RequestMapping(value="/{folderId}", method = GET)
    public Folder returnFolderById(@PathVariable("folderId") Integer folderId) {
        return service.getOneById(folderId);
    }
}