if you want to fetch data from header, use RequestHeader , similar to RequestParam

Brother, you have all got the token, and then convert the token into a user object and return it according to the conversion rules of your system.

the first type:

@PostMapping("add")
    @ResponseBody
    public Comment commentAdd(@RequestBody CommentAddVO VO, HttpServletRequest request) {
        String headerToken = request.getHeader("token");       
        User user = .....;//tokenuser
         Comment comment =  comRep.save(VO.toComment(user));
        //
        return comment;
    }

if you find it troublesome, you can write a basic controller, such as the class name BaseController. Your controller inherits the BaseController,. Write a method to get the user logic in BaseController and call it when you use user.

second: use your UserUtil

public class UserUtil {
    
    public static User getUser() {
        //
        HttpServletRequest request = ((ServletRequestAttributes)RequestContextHolder.getRequestAttributes()).getRequest();
        String headerToken = request.getHeader("token");
        User user = .....;//tokenuser
        return user;
    }
}

@PostMapping("add")
    @ResponseBody
    public Comment commentAdd(@RequestBody CommentAddVO VO) {
        String headerToken = request.getHeader("token");       
        User user = UserUtil.getUser();
         Comment comment =  comRep.save(VO.toComment(user));
        //
        return comment;
    }

third: if you have to do it your way, pass in the user object.
write a filter or interceptor to get the token, and convert it to a user object, and then put it into the request, as mentioned above.

if useful to spring security, you can use the @ AuthenticationPrincipal annotation to achieve this effect.