[FEAT] 바코드에서 조회한 책 DB 존재 여부 판단 로직 구현

src/main/java/org/vsa/server/book/controller/BarcodeController.java

@@ -9,11 +9,14 @@
 import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.multipart.MultipartFile;
 import org.vsa.server.book.dto.response.BarcodeInfoResponse;
+import org.vsa.server.book.dto.response.BookInfoFromBarcodeResponse;
+import org.vsa.server.book.entity.Book;
 import org.vsa.server.book.service.AladinService;
 import org.vsa.server.book.service.BarcodeService;
 
 import java.io.File;
 import java.io.IOException;
+import java.util.Optional;
 
 @RequiredArgsConstructor
 @RestController
@@ -39,7 +42,27 @@ public ResponseEntity<?> extractBarcode(@RequestParam("file") MultipartFile file
             // 임시 파일 삭제
             tempFile.delete();
 
-            return ResponseEntity.ok(bookInfo);
+            // DB에서 책 존재 여부 확인
+            Optional<Book> existingBook = barcodeService.findByTitleAndPublisher(bookInfo.getTitle(), bookInfo.getPublisher());
+
+            if (existingBook.isPresent()) {
+                // 책이 존재할 경우 bookId, title, publisher 반환
+                Book book = existingBook.get();
+                BookInfoFromBarcodeResponse response = BookInfoFromBarcodeResponse.builder()
+                        .bookId(book.getBookId())
+                        .title(book.getTitle())
+                        .publisher(book.getPublisher())
+                        .build();
+                return ResponseEntity.ok(response);
+            } else {
+                // 책이 존재하지 않을 경우 title, publisher, 메시지 반환
+                BookInfoFromBarcodeResponse response = BookInfoFromBarcodeResponse.builder()
+                        .title(bookInfo.getTitle())
+                        .publisher(bookInfo.getPublisher())
+                        .message("해당 도서는 데이터베이스에 존재하지 않습니다.")
+                        .build();
+                return ResponseEntity.status(HttpStatus.NOT_FOUND).body(response);
+            }
         } catch (IOException e) {
             return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR)
                     .body("Error processing the uploaded file");

src/main/java/org/vsa/server/book/dto/response/BookInfoFromBarcodeResponse.java

@@ -0,0 +1,13 @@
+package org.vsa.server.book.dto.response;
+
+import lombok.Builder;
+import lombok.Getter;
+
+@Builder
+@Getter
+public class BookInfoFromBarcodeResponse {
+    private Long bookId; // 존재하는 경우에만 반환
+    private String title;
+    private String publisher;
+    private String message; // 존재하지 않는 경우에만 반환
+}

src/main/java/org/vsa/server/book/repository/BookRepository.java

@@ -10,6 +10,7 @@
 import org.springframework.stereotype.Repository;
 
 import java.util.List;
+import java.util.Optional;
 
 @Repository
 public interface BookRepository extends JpaRepository<Book, Long> {
@@ -42,5 +43,7 @@ public interface BookRepository extends JpaRepository<Book, Long> {
     @Query("SELECT b FROM Book b JOIN Bookmark bm ON b.bookId = bm.book.bookId WHERE bm.member.memberId = :memberId")
     Page<Book> findBooksByMember(@Param("memberId") Long memberId, Pageable pageable);
 
+    Optional<Book> findByTitleAndPublisher(String title, String publisher);
+
 
 }

src/main/java/org/vsa/server/book/service/BarcodeService.java

@@ -5,17 +5,22 @@
 import com.google.zxing.common.HybridBinarizer;
 import lombok.RequiredArgsConstructor;
 import org.springframework.stereotype.Service;
+import org.vsa.server.book.entity.Book;
+import org.vsa.server.book.repository.BookRepository;
 
 import javax.imageio.ImageIO;
 import java.awt.image.BufferedImage;
 import java.io.File;
 import java.io.IOException;
+import java.util.Optional;
 
 
 @Service
 @RequiredArgsConstructor
 public class BarcodeService {
 
+    private final BookRepository bookRepository;
+
     public String extractISBN(String imagePath) {
         try {
             // 이미지 파일 읽기
@@ -40,4 +45,8 @@ public String extractISBN(String imagePath) {
             throw new RuntimeException("바코드 인식 실패: " + e.getMessage(), e);
         }
     }
+
+    public Optional<Book> findByTitleAndPublisher(String title, String publisher) {
+        return bookRepository.findByTitleAndPublisher(title, publisher);
+    }
 }