<aside> 📌 우리는 스프링 컨테이너의 개념을 배우고, 기존에 작성했던 Controller 코드를 3단 분리해보았습니다. 앞으로 API를 개발할 때는 이 계층에 맞게 각 코드가 작성되어야 합니다! 🙂

과제 #4 에서 만들었던 API를 분리해보며, Controller - Service - Repository 계층에 익숙해져 봅시다! 👍

</aside>

[문제 1 - Controller - Service - Repository 분리]

• Controller

  @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);
      }
  
      @GetMapping("/api/v1/fruit/stat")
      public FruitAmountResponse calculateAmountFruit(@RequestParam String name) {
          FruitAmountResponse response = fruitService.calculateAmountFruit(name);
          return response;
      }
  }
  

• 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) {
          if (fruitRepository.isFruitExist(request.getId())) {
              throw new IllegalArgumentException();
          }
          fruitRepository.updateFruit(request.getId());
      }
  
      public FruitAmountResponse calculateAmountFruit(String name) {
          if (fruitRepository.isFruitExist(name)) {
              throw new IllegalArgumentException();
          }
          return fruitRepository.calculateAmountFruit(name);
      }
  }
  

• Repository

  @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, warehousing_date, price) VALUES(?, ? ,?)";
          jdbcTemplate.update(sql, name, warehousingDate, price);
      }
  
      public boolean isFruitExist(long id) {
          String readSql = "SELECT * FROM fruit WHERE id = ?";
          return jdbcTemplate.query(readSql, (rs, rowNum) -> 0, id).isEmpty();
      }
  
      public void updateFruit(long id) {
          String sql = "UPDATE fruit SET is_sold = true WHERE id = ?";
          jdbcTemplate.update(sql, id);
      }
  
      public boolean isFruitExist(String name) {
          String readSql = "SELECT * FROM fruit WHERE name = ?";
          return jdbcTemplate.query(readSql, (rs, rowNum) -> 0, name).isEmpty();
      }
  
      public FruitAmountResponse calculateAmountFruit(String name) {
          String soldSql = "SELECT SUM(price) FROM fruit WHERE name = ? AND is_sold = true";
          String notSoldSql = "SELECT SUM(price) FROM fruit WHERE name = ? AND is_sold = false";
  
          Long salesAmount = jdbcTemplate.queryForObject(soldSql, Long.class, name);
          Long notSalesAmount = jdbcTemplate.queryForObject(notSoldSql, Long.class, name);
  
          return new FruitAmountResponse(salesAmount, notSalesAmount);
  
      }
  }
  

[문제 2 - Repository 분리, @Primary 활용]

• FruitRepository 생성 및 FruitMemoryRepository, FruitMysqlRepository 분리

  public interface FruitRepository {
      void saveFruit(String name, LocalDate warehousingDate, long price);
      boolean isFruitExist(long id);
      void updateFruit(long id);
      boolean isFruitExist(String name);
      FruitAmountResponse calculateAmountFruit(String name);
  }
  

  @Repository
  public class FruitMysqlRepository implements FruitRepository{
  		...
  }
  

  @Repository
  public class FruitMemoryRepository implements FruitRepository{
  		...
  }
  

• @Primary를 사용하지 않았을 경우

  Parameter 0 of constructor in com.example.tasks.task4.FruitService required a single bean, but 2 were found:
  	- fruitMemoryRepository: defined in file [/Users/heek/inflearn-study-be/project/tasks/build/classes/java/main/com/example/tasks/task4/FruitMemoryRepository.class]
  	- fruitMysqlRepository: defined in file [/Users/heek/inflearn-study-be/project/tasks/build/classes/java/main/com/example/tasks/task4/FruitMysqlRepository.class]
  
  

• @Primary 를 사용하여 스위칭

  @Primary
  @Repository
  public class FruitMysqlRepository implements FruitRepository{
  		...
  }
  

  @Primary
  @Repository
  public class FruitMemoryRepository implements FruitRepository{
  		...
  }