[spring入門]調査向けプログラミング

金栄漢先生.頑張ります.

AOPが必要

シナリオ:すべてのメソッドの呼び出し時間を測定しますか?
メンバークエリー時間測定の追加
論理終了時計時

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;

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


    // 회원가입
    public Long join(Member member) {
        long start = System.currentTimeMillis();

        try {
            validateDuplicateMember(member); //중복 회원 검증
            memberRepository.save(member);
            return member.getId();
        } finally {
            long finish = System.currentTimeMillis();
            long timeMs = finish - start;
            System.out.println("join " + timeMs + "ms");
        }
    }

    private void validateDuplicateMember(Member member) {
        memberRepository.findByName(member.getName())
                .ifPresent(m -> {
                    throw new IllegalStateException("이미 존재하는 회원입니다.");
                });
    }
    //전체 회원조회
    public List<Member> findMembers() {
        long start = System.currentTimeMillis();
        try {
            return memberRepository.findAll();
        } finally {
            long finish = System.currentTimeMillis();
            long timeMs = finish - start;
            System.out.println("findMembers " + timeMs + "ms");
        }
    }

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

共通の注目点と重要な注目点を共有(分離)
方法に貼るのではなく、必要なところに共通の関心事項を適用します!

AOPの適用

hello.hellospringサブアイテムにaopフォルダを作成し、TimeTraceAOPクラスを作成

package hello.hellospring.aop;

import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.springframework.stereotype.Component;
@Component
@Aspect
public class TimeTraceAop {
    @Around("execution(* hello.hellospring..*(..))")
    public Object execute(ProceedingJoinPoint joinPoint) throws Throwable {
        long start = System.currentTimeMillis();
        System.out.println("START: " + joinPoint.toString());
        try {
            return joinPoint.proceed();
        } finally {
            long finish = System.currentTimeMillis();
            long timeMs = finish - start;
            System.out.println("END: " + joinPoint.toString()+ " " + timeMs +
                    "ms");
        }
    }
}

前回使用したコードセット
https://github.com/Vector1331/hello-spring