上一章 Day 13 - 什麼是IOC控制反轉? 什麼是DI依賴注入?

今天要用Service層來示範如何實作

在專案下新增一個Service資料夾, 並在其底下新增一個Interface

MemberService.java

public interface MemberService {

    public Member saveMember(Member member);

}

然後在Service資料夾底下再新增一個impl資料夾

新增MemberServiceImpl.java

@Service
public class MemberServiceImpl implements MemberService {

    @Autowired
    private MemberRepository memberRepository;

    @Override
    public Member saveMember(Member member) {
        member.setMid(UUID.randomUUID().toString().replaceAll("-", ""));
        member.setCreateTime(new Date());
        memberRepository.save(member);
        return member;
    }

}

結構大概是這樣

修改一下我們的MemberController

@RestController
@RequestMapping("/api")
public class MemberController {

    @Autowired
    private MemberRepository memberRepository;
    @Autowired
    private MemberService memberService;

    @GetMapping("/members")
    public Collection<Member> members() {
        return memberRepository.findAll();
    }

    @GetMapping("/member/{id}")
    public ResponseEntity<?> getMember(@PathVariable Long id) {
        Optional<Member> member = memberRepository.findById(id);
        return member.map(response -> ResponseEntity.ok().body(response))
                .orElse(new ResponseEntity<>(HttpStatus.NOT_FOUND));
    }

    @PostMapping("/member")
    public ResponseEntity<Member> createMember(@Valid @RequestBody Member member) throws Exception {
        Member result = memberService.saveMember(member);
        return ResponseEntity.ok().body(result);
    }

    @PutMapping("/member/{id}")
    public ResponseEntity<Member> updateMember(@Valid @RequestBody Member member) {
        Member result = memberRepository.save(member);
        return ResponseEntity.ok().body(result);
    }

    @DeleteMapping("/member/{id}")
    public ResponseEntity<?> deleteMember(@PathVariable Long id){
        memberRepository.deleteById(id);
        return ResponseEntity.ok().build();
    }

}

可以看到我們是以@Autowired的方式, 注入MemberService, 讓Spring幫我們管理

現在我們增刪查改功能全都有了, 目前為止都是用H2 Database

下一章正式進入MySQL Database

Day 15 - MySQL 手動建立Schema與Table