SpringBoot @PathVariable使用时遇到的问题及解决

/**
     * 查询客户详细信息
     * BY Oliver_Deng
     * @param userId 用户id
     * @return
     */
    @ApiOperation(value="查询客户详细信息",notes = "根据传入id查询客户详细信息")
    @ApiResponses({@ApiResponse(code=400,message="请求参数没填好")})
    @ApiImplicitParam(paramType = "query", name = "userId", dataType = "Integer", required = true, value = "客户id")
    @GetMapping("/findCustomerDetailByUserId/{userId}")
    public Result<Map<String,Object>> findCustomerByUserId(@PathVariable Integer userId){
        //客户信息
//        CustomerListVo customerMessage = customerUserService.findCustomerByUserID(userId);
        //客户车辆信息
//        List<CustomerUserCar> cars = customerUserCarService.findCarByUserId(Integer.valueOf(userId)); //not finish yet
        //TODO 计次卡、储值卡
        return null;
    }

/**
 * 查询车辆品牌、车系、年款、车型信息
 * BY Oliver_Deng
 * @param brandId 车辆品牌ID
 * @param familyId 车系ID
 * @param groupId 车辆年款ID
 * @return
 */
@ApiOperation(value="查询车辆品牌、车系、年款、车型信息",notes = "查询车辆品牌、车系、年款、车型信息，传入子id时先将上级id清空，一次访问只能传入一种id或者不传id")
@ApiImplicitParams({
        @ApiImplicitParam(paramType = "query", name = "brandId", dataType = "String", required = false, value = "车辆品牌ID"),
        @ApiImplicitParam(paramType = "query", name = "familyId", dataType = "String", required = false, value = "车系ID"),
        @ApiImplicitParam(paramType = "query", name = "groupId", dataType = "String", required = false, value = "车辆年款ID")
})
@ApiResponses({@ApiResponse(code=400,message="请求参数没填好")})
@GetMapping("/findCarBrandMessage/{brandId}/{familyId}/{groupId}")
public Result findCarBrandMessage(@PathVariable String brandId,@PathVariable String familyId,@PathVariable String groupId){
    return customerUserCarService.findCarBrandMessage(brandId,familyId,groupId);
}