Controller层

@RestController
@RequestMapping("/car")
public class CarController {

    @PostMapping("/list")
    public ResultBean<CarVO> list(@Valid @RequestBody QueryCarRequest request, BindingResult bindingResult) {
        if (bindingResult.hasErrors()) {
        	// 所有没有通过验证的字段都会保存在bindingResult内
            List<FieldError> fieldErrors = bindingResult.getFieldErrors();
            // 只取第一个错误消息并返回，比如“车牌不能为空”
            String err = fieldErrors.get(0).getDefaultMessage();
            ResultBean resultBean = new ResultBean<>();
            resultBean.fail(err);
            return resultBean;
        }
        return carBusi.list(request);
    }
}

CarRequest传参

@Data