<과제>

문제 1. 과제 #4 에서 만들었던 API를 강의 내용처럼 Controller - Service - Repository로 분리해보세요!

• FruitController

package com.group.libraryapp.controller.assignment;

import com.group.libraryapp.dto.fruit.FruitCreateRequest;
import com.group.libraryapp.dto.fruit.FruitUpdateRequest;
import com.group.libraryapp.service.assignment.FruitService;
import org.springframework.web.bind.annotation.*;

@RestController
public class FruitController {
    private final FruitService fruitService;

    public FruitController(FruitService fruitService) {
        this.fruitService = fruitService;
    }

    @PostMapping("/api/v1/fruit")
    public void saveFruit(@RequestBody FruitCreateRequest request) {
        fruitService.saveFruit(request);
    }

    @PutMapping("/api/v1/fruit")
    public void updateFruit(@RequestBody FruitUpdateRequest request) {
        fruitService.updateFruit(request);
    }

}

• FruitService

package com.group.libraryapp.service.assignment;

import com.group.libraryapp.dto.fruit.FruitCreateRequest;
import com.group.libraryapp.dto.fruit.FruitUpdateRequest;
import com.group.libraryapp.repository.assignment.FruitRepository;
import org.springframework.stereotype.Service;

@Service
public class FruitService {
    private final FruitRepository fruitRepository;

    public FruitService(FruitRepository fruitRepository) {
        this.fruitRepository = fruitRepository;
    }

    public void saveFruit(FruitCreateRequest request) {
        fruitRepository.saveFruit(request.getName(), request.getWarehousingDate(), request.getPrice());
    }

    public void updateFruit(FruitUpdateRequest request) {
        boolean isFruitNotExist = fruitRepository.isFruitNotExist(request.getId());
        if (isFruitNotExist) {
            throw new IllegalArgumentException();
        }
        fruitRepository.updateFruit(request.getName(), request.getWarehousingDate(), request.getPrice(), request.getId());
    }
}

• FruitRepository

package com.group.libraryapp.repository.assignment;

import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.stereotype.Repository;

import java.time.LocalDate;

@Repository
public class FruitRepository {
    private final JdbcTemplate jdbcTemplate;

    public FruitRepository(JdbcTemplate jdbcTemplate) {
        this.jdbcTemplate = jdbcTemplate;
    }

    public void saveFruit(String name, LocalDate warehousingDate, long price) {
        String sql = "INSERT INTO fruit (name, warehousingDate, price) VALUES (?, ?, ?)";
        jdbcTemplate.update(sql, name, warehousingDate, price);
    }

    public boolean isFruitNotExist(long id) {
        String readSql = "SELECT * FROM fruit WHERE id = ?";
        return jdbcTemplate.query(readSql, (rs, rowNum) -> 0, id).isEmpty();
    }

    public void updateFruit(String name, LocalDate warehousingDate, long price, long id) {
        String sql = "UPDATE fruit SET name = ?, warehousingDate = ?, price = ? WHERE id = ?";
        jdbcTemplate.update(sql, name, warehousingDate, price, id);
    }
}

문제 2. 문제 1에서 분리되면 FruitController / FruitService / FruitRepository가 생겼을 것입니다. 기존에 작성했던 FruitRepository를 FruitMemoryRepository와 FruitMySqlRepository로 나누고 @Primary 어노테이션을 활용해 두 Repository를 바꿔가며 동작시킬 수 있도록 코드를 변경해보세요!

• FruitRepository

package com.group.libraryapp.repository.assignment;

public interface FruitRepository {
    void saveFruit();
    boolean isFruitNotExist();
    void updateFruit();
}

• FruitMemoryRepository

package com.group.libraryapp.repository.assignment;

import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.stereotype.Repository;

import java.time.LocalDate;

@Repository
public class FruitMemoryRepository {
    private final JdbcTemplate jdbcTemplate;

    public FruitMemoryRepository(JdbcTemplate jdbcTemplate) {
        this.jdbcTemplate = jdbcTemplate;
    }

    public void saveFruit(String name, LocalDate warehousingDate, long price) {
        String sql = "INSERT INTO fruit (name, warehousingDate, price) VALUES (?, ?, ?)";
        jdbcTemplate.update(sql, name, warehousingDate, price);
    }

    public boolean isFruitNotExist(long id) {
        String readSql = "SELECT * FROM fruit WHERE id = ?";
        return jdbcTemplate.query(readSql, (rs, rowNum) -> 0, id).isEmpty();
    }

    public void updateFruit(String name, LocalDate warehousingDate, long price, long id) {
        String sql = "UPDATE fruit SET name = ?, warehousingDate = ?, price = ? WHERE id = ?";
        jdbcTemplate.update(sql, name, warehousingDate, price, id);
    }
}

• FruitMySqlRepository(이 repository를 사용한다고 가정)

package com.group.libraryapp.repository.assignment;

import org.springframework.context.annotation.Primary;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.stereotype.Repository;

import java.time.LocalDate;

@Primary
@Repository
public class FruitMySqlRepository {
    private final JdbcTemplate jdbcTemplate;

    public FruitMySqlRepository(JdbcTemplate jdbcTemplate) {
        this.jdbcTemplate = jdbcTemplate;
    }

    public void saveFruit(String name, LocalDate warehousingDate, long price) {
        String sql = "INSERT INTO fruit (name, warehousingDate, price) VALUES (?, ?, ?)";
        jdbcTemplate.update(sql, name, warehousingDate, price);
    }

    public boolean isFruitNotExist(long id) {
        String readSql = "SELECT * FROM fruit WHERE id = ?";
        return jdbcTemplate.query(readSql, (rs, rowNum) -> 0, id).isEmpty();
    }

    public void updateFruit(String name, LocalDate warehousingDate, long price, long id) {
        String sql = "UPDATE fruit SET name = ?, warehousingDate = ?, price = ? WHERE id = ?";
        jdbcTemplate.update(sql, name, warehousingDate, price, id);
    }
}