회원 웹 기능

home.html

 

createMemberForm.html

memberList.html

 

MemberController

package hello.hellospring.controller;

import hello.hellospring.domain.Member;
import hello.hellospring.service.MemberService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;

import java.util.List;

@Controller
public class MemberController {

    private final MemberService memberService;

    @Autowired
    public MemberController(MemberService memberService) {
        this.memberService = memberService;
    }

    @GetMapping("/members/new")
    public String createFrom(){
        return "members/createMemberForm";
    }

    @PostMapping("/members/new")
    public String create(Member form){
        Member member = new Member();
        member.setName(form.getName());

        memberService.join(member);
        return "redirect:/";
    }

    @GetMapping("/members")
    public String list(Model model){
        List<Member> members = memberService.findMembers();
        model.addAttribute("members" , members);
        return "members/memberList";
    }
}

MemberService

package hello.hellospring.service;

import hello.hellospring.domain.Member;
import hello.hellospring.repository.MemberRepository;
import hello.hellospring.repository.MemoryMemberRepository;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.List;
import java.util.Optional;

public class MemberService {
    private final MemberRepository memberRepository;

    @Autowired
    public MemberService(MemberRepository memberRepository) {
        this.memberRepository = memberRepository;
    }

    /**
     * 회원 가입
     */
    public Long join(Member member){
        // 같은 이름이 있는 중복 회원은 안된다.
        validateDuplicateMember(member);

        memberRepository.save(member);
        return member.getId();
    }

    private void validateDuplicateMember(Member member) {
        memberRepository.findByName(member.getName())
                .ifPresent( m -> {
                    throw new IllegalStateException("이미 존재하는 회원입니다.");
                });
    }

    /**
     * 전체 회원조회
     */
    public List<Member> findMembers(){
        return memberRepository.findAll();
    }

    /**
     * 회원조회
     */
    public Optional<Member> findOne(Long memberId){
        return memberRepository.findById(memberId);
    }
}

* findByName의 반환 값이 Optinal객체 이기 때문에 .ifPresent 호출이 가능하다

(findByName의 반환값이 존재할 경우 예외 발생 - 중복 체크 , null일 경우 실행 하지 않는다)

스프링 입문 - 코드로 배우는 스프링 부트, 웹 MVC, DB 접근 기술 - 인프런