feat: 마이바(MyBar) 목록 조회 서비스 로직 구현

Author: MEOHIN

src/main/java/com/back/domain/mybar/service/MyBarService.java

@@ -0,0 +1,36 @@
+package com.back.domain.mybar.service;
+
+import com.back.domain.mybar.dto.MyBarItemResponseDto;
+import com.back.domain.mybar.dto.MyBarListResponseDto;
+import com.back.domain.mybar.entity.MyBar;
+import com.back.domain.mybar.enums.KeepStatus;
+import com.back.domain.mybar.repository.MyBarRepository;
+import lombok.RequiredArgsConstructor;
+import org.springframework.data.domain.Page;
+import org.springframework.data.domain.PageRequest;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+import java.util.ArrayList;
+import java.util.List;
+
+@Service
+@RequiredArgsConstructor
+public class MyBarService {
+
+    private final MyBarRepository myBarRepository;
+
+    @Transactional(readOnly = true)
+    public MyBarListResponseDto getMyBar(Long userId, int page, int pageSize) {
+        Page<MyBar> myBarPage = myBarRepository.findByUserIdAndStatusOrderByIdDesc(userId, KeepStatus.ACTIVE, PageRequest.of(page, pageSize));
+
+        List<MyBar> myBars = myBarPage.getContent();
+        List<MyBarItemResponseDto> items = new ArrayList<>();
+        for (MyBar myBar : myBars) items.add(MyBarItemResponseDto.from(myBar));
+
+        boolean hasNext = myBarPage.hasNext();
+        Integer nextPage = hasNext ? myBarPage.getNumber() + 1 : null;
+
+        return new MyBarListResponseDto(items, hasNext, nextPage);
+    }
+}