[스프링MVC - 1편] 스프링 MVC 시작

스프링 MVC - 시작하기

@RequestMapping

스프링은 애노테이션을 활용한 매우 유연하고, 실용적인 컨트롤러를 만들었는데 이것이 바로 @RequestMapping 애노테이션을 사용하는 컨트롤러이다

• RequestMappingHandlerMapping
• RequestMappingHandlerAdapter

 

 

 

1. SpringMemberFormControllerV1 - 회원 등록 폼

@Controller
public class SpringMemberFormControllerV1 {
    @RequestMapping("/springmvc/v1/members/new-form")
    public ModelAndView process() {
        return new ModelAndView("new-form");
    }
}

• @Controller
  • 스프링이 자동으로 스프링 빈으로 등록한다 (내부에 @Component 애노테이션이 있어서 컴포넌트 스캔의 대상이 됨)
  • 스프링 MVC에서 애노테이션 기반 컨트롤러로 인식한다

• @RequestMapping : 요청 정보를 매핑한다 해당 URL이 호출되면 이 메서드가 호출된다
• ModelAndView : 모델과 뷰 정보를 담아서 반환하면 된다

 

 

 

2. SpringMemberSaveControllerV1 - 회원 저장

@Controller
public class SpringMemberSaveControllerV1 {

    private MemberRepository memberRepository = MemberRepository.getInstance();

    @RequestMapping("/springmvc.v1/members/save")
    public ModelAndView process(HttpServletRequest request, HttpServletResponse response) {
        String username = request.getParameter("username");
        int age = Integer.parseInt(request.getParameter("age"));

        Member member = new Member(username, age);
        memberRepository.save(member);

        ModelAndView mv = new ModelAndView("save-result");
        mv.addObject("member", member);
        return mv;
    }
}

 

 

 

3. SpringMemberListControllerV1 - 회원 목록

@Controller
public class SpringMemberListControllerV1 {
    private MemberRepository memberRepository = MemberRepository.getInstance();

    @RequestMapping("/springmvc/v1/members")
    public ModelAndView process() {
        List<Member> members = memberRepository.findAll();
        ModelAndView mv = new ModelAndView("members");
        mv.addObject("members", members);
        return mv;
    }
}

 

 

 

스프링 MVC - 컨트롤러 통합

1. SpringMemberControllerV2

@Controller
@RequestMapping("/springmvc/v2/members")
public class SpringMemberControllerV2 {

    private MemberRepository memberRepository = MemberRepository.getInstance();

    @RequestMapping("/new-form")
    public ModelAndView newForm() {
        return new ModelAndView("new-form");
    }

    @RequestMapping
    public ModelAndView members() {
        List<Member> members = memberRepository.findAll();
        ModelAndView mv = new ModelAndView("members");
        mv.addObject("members", members);
        return mv;
    }

    @RequestMapping("/save")
    public ModelAndView save(HttpServletRequest request, HttpServletResponse response) {
        String username = request.getParameter("username");
        int age = Integer.parseInt(request.getParameter("age"));

        Member member = new Member(username, age);
        memberRepository.save(member);

        ModelAndView mv = new ModelAndView("save-result");
        mv.addObject("member", member);
        return mv;
    }

}

 

 

 

스프링 MVC - 실용적인 방식

1. SpringMemberControllerV3

@Controller
@RequestMapping("/springmvc/v3/members")
public class SpringMemberControllerV3 {

    private MemberRepository memberRepository = MemberRepository.getInstance();

    // @RequestMapping(value = "/new-form", method = RequestMethod.GET)
    @GetMapping("/new-form")
    public ModelAndView newForm() {
        return new ModelAndView("new-form");
    }

    // @RequestMapping(value = "/save", method = RequestMethod.POST)
    @PostMapping("/save")
    public String save(
            @RequestParam("username") String username,
            @RequestParam("age") int age,
            Model model) {
        Member member = new Member(username, age);
        memberRepository.save(member);

        model.addAttribute("member", member);
        return "save-result";
    }

    // @RequestMapping(method = RequestMethod.GET)
    @GetMapping
    public String members(Model model) {
        List<Member> members = memberRepository.findAll();
        model.addAttribute("members", members);
        return "members";
    }

}

• Model 파라미터 - save(), members()를 보면 Model을 파라미터로 받는 것을 확인할 수 있다
• ViewName 직접반환 - 뷰의 논리 이름을 반환할 수 있다
• @RequestParam 사용 - 스프링은 HTTP 요청 파라미터를 @RequestParam으로 받을 수 있다
• @RequestMapping @GetMapping, @PostMapping - @RequestMapping은 URL만 매칭하는 것이 아니라 HTTP Method도 함께 구분할 수 있다