인프런 커뮤니티 질문&답변

안녕하세요 MVC 1편을 수강 중입니다. 강의에서는 파라미터와 이름이 같으면 생략이 가능하다고 하는데,
저는 그 지점이 잘 안되는 것 같아요. 코드랑 오류 올리겠습니다 ㅠ 어디가 문제인지 찾아주시면 감사하겠습니다.

package hello.springmvc.basic.request;


import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;

import java.io.IOException;

@Controller
@Slf4j
public class RequestParamController {

    @RequestMapping("/request-param-v1")
    public void requestParamV1(HttpServletRequest request, HttpServletResponse response) throws IOException {
        String username = request.getParameter("username");
        int age = Integer.parseInt(request.getParameter("age"));
        log.info("username={}, age={}", username,age);

        response.getWriter().write("ok");
    }



    @ResponseBody
    @RequestMapping("/request-param-v2")
    public String requestParamV2(@RequestParam("username") String memberName,
                                 @RequestParam("age") int memberAge
                                 )
    {

        log.info("username={}, age={}", memberName,memberAge);

        return "ok";
    }

    @ResponseBody
    @RequestMapping("/request-param-v3")
    public String requestParamV3(@RequestParam String username,
                                 @RequestParam int age
    )
    {
        log.info("username={}, age={}", username,age);
        return "ok";
    }
    @ResponseBody
    @RequestMapping("/request-param-v4")
    public String requestParamV4(String username, int age)
    {
        log.info("username={}, age={}", username,age);
        return "ok";
    }

    @ResponseBody
    @RequestMapping("/request-param-required")
    public String requestParamRequired(@RequestParam(required = false) String username, @RequestParam(required = false) int age)
    {
        log.info("username={}, age={}", username,age);
        return "ok";
    }

    @ResponseBody
    @RequestMapping("/request-param-default")
    public String requestParamDefault(@RequestParam(required = false, defaultValue = "guest") String username, @RequestParam(required = false, defaultValue = "-1") int age)
    {
        log.info("username={}, age={}", username,age);
        return "ok";
    }


}

java.lang.IllegalArgumentException: Name for argument of type [java.lang.String] not specified, and parameter name information not available via reflection. Ensure that the compiler uses the '-parameters' flag.