refactor: 도메인 전체 리팩토링

src/main/java/com/threestar/trainus/domain/comment/controller/CommentController.java

@@ -16,11 +16,11 @@
 import com.threestar.trainus.domain.comment.dto.CommentPageResponseDto;
 import com.threestar.trainus.domain.comment.dto.CommentResponseDto;
 import com.threestar.trainus.domain.comment.service.CommentService;
+import com.threestar.trainus.global.annotation.LoginUser;
 import com.threestar.trainus.global.unit.BaseResponse;
 
 import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.tags.Tag;
-import jakarta.servlet.http.HttpSession;
 import jakarta.validation.Valid;
 import lombok.RequiredArgsConstructor;
 
@@ -37,8 +37,7 @@ public class CommentController {
 	@PostMapping("/{lessonId}")
 	@Operation(summary = "댓글 작성", description = "레슨 ID에 해당되는 댓글을 작성합니다.")
 	public ResponseEntity<BaseResponse<CommentResponseDto>> createComment(@PathVariable Long lessonId,
-		@Valid @RequestBody CommentCreateRequestDto request, HttpSession session) {
-		Long userId = (Long)session.getAttribute("LOGIN_USER");
+		@Valid @RequestBody CommentCreateRequestDto request, @LoginUser Long userId) {
 		CommentResponseDto comment = commentService.createComment(request, lessonId, userId);
 		return BaseResponse.ok("댓글 등록 완료되었습니다", comment, HttpStatus.CREATED);
 	}
@@ -56,9 +55,8 @@ public ResponseEntity<BaseResponse<CommentPageResponseDto>> readAll(@PathVariabl
 
 	@DeleteMapping("/{commentId}")
 	@Operation(summary = "댓글 삭제", description = "댓글 ID에 해당되는 댓글을 삭제합니다.")
-	public ResponseEntity<Void> deleteComment(@PathVariable Long commentId, HttpSession session) {
-		Long userId = (Long)session.getAttribute("LOGIN_USER");
+	public ResponseEntity<BaseResponse<Void>> deleteComment(@PathVariable Long commentId, @LoginUser Long userId) {
 		commentService.delete(commentId, userId);
-		return ResponseEntity.noContent().build();
+		return BaseResponse.okOnlyStatus(HttpStatus.NO_CONTENT);
 	}
 }

src/main/java/com/threestar/trainus/domain/comment/dto/CommentCreateRequestDto.java

@@ -2,9 +2,9 @@
 
 import jakarta.validation.constraints.NotBlank;
 import jakarta.validation.constraints.Size;
-import lombok.Data;
+import lombok.Getter;
 
-@Data
+@Getter
 public class CommentCreateRequestDto {
 	@NotBlank(message = "댓글 내용은 필수입니다")
 	@Size(max = 255, message = "댓글은 255자 이내여야 합니다.")

src/main/java/com/threestar/trainus/domain/comment/service/CommentService.java

@@ -12,11 +12,9 @@
 import com.threestar.trainus.domain.comment.mapper.CommentMapper;
 import com.threestar.trainus.domain.comment.repository.CommentRepository;
 import com.threestar.trainus.domain.lesson.admin.entity.Lesson;
-import com.threestar.trainus.domain.lesson.admin.repository.LessonRepository;
+import com.threestar.trainus.domain.lesson.admin.service.AdminLessonService;
 import com.threestar.trainus.domain.user.entity.User;
-import com.threestar.trainus.domain.user.repository.UserRepository;
-import com.threestar.trainus.global.exception.domain.ErrorCode;
-import com.threestar.trainus.global.exception.handler.BusinessException;
+import com.threestar.trainus.domain.user.service.UserService;
 import com.threestar.trainus.global.utils.PageLimitCalculator;
 
 import lombok.RequiredArgsConstructor;
@@ -25,16 +23,14 @@
 @RequiredArgsConstructor
 public class CommentService {
 
-	private final UserRepository userRepository;
-	private final LessonRepository lessonRepository;
+	private final AdminLessonService adminLessonService;
 	private final CommentRepository commentRepository;
+	private final UserService userService;
 
 	@Transactional
 	public CommentResponseDto createComment(CommentCreateRequestDto request, Long lessonId, Long userId) {
-		Lesson findLesson = lessonRepository.findById(lessonId)
-			.orElseThrow(() -> new BusinessException(ErrorCode.LESSON_NOT_FOUND));
-		User findUser = userRepository.findById(userId)
-			.orElseThrow(() -> new BusinessException(ErrorCode.USER_NOT_FOUND));
+		Lesson findLesson = adminLessonService.findLessonById(lessonId);
+		User findUser = userService.getUserById(userId);
 		Comment parent = findParent(request);
 
 		Comment newComment = Comment.builder()

src/main/java/com/threestar/trainus/domain/coupon/user/dto/CouponResponseDto.java

@@ -20,21 +20,7 @@ public class CouponResponseDto {
 	private LocalDateTime expirationDate;
 	private OwnedStatus ownedStatus;
 	private Integer quantity;
-	private String category;
+	private CouponCategory category;
 	private LocalDateTime openTime;
 
-	public CouponResponseDto(Long couponId, String couponName, String discountPrice,
-		Integer minOrderPrice, LocalDateTime expirationDate,
-		String ownedStatus, Integer quantity, CouponCategory category,
-		LocalDateTime openTime) {
-		this.couponId = couponId;
-		this.couponName = couponName;
-		this.discountPrice = discountPrice;
-		this.minOrderPrice = minOrderPrice;
-		this.expirationDate = expirationDate;
-		this.ownedStatus = OwnedStatus.valueOf(ownedStatus);
-		this.quantity = quantity;
-		this.category = category.name();
-		this.openTime = openTime;
-	}
 }

src/main/java/com/threestar/trainus/domain/coupon/user/dto/CreateUserCouponResponseDto.java

@@ -3,6 +3,7 @@
 import java.time.LocalDateTime;
 
 import com.fasterxml.jackson.annotation.JsonFormat;
+import com.threestar.trainus.domain.coupon.user.entity.CouponStatus;
 
 import lombok.Builder;
 import lombok.Getter;
@@ -15,6 +16,6 @@ public class CreateUserCouponResponseDto {
 	@JsonFormat(pattern = "yyyy-MM-dd'T'HH:mm:ss")
 	private LocalDateTime createdAt;
 	private LocalDateTime expirationDate;
-	private String status;
+	private CouponStatus status;
 
 }

src/main/java/com/threestar/trainus/domain/coupon/user/dto/UserCouponResponseDto.java

@@ -2,6 +2,8 @@
 
 import java.time.LocalDateTime;
 
+import com.threestar.trainus.domain.coupon.user.entity.CouponStatus;
+
 import lombok.Builder;
 import lombok.Getter;
 
@@ -13,6 +15,6 @@ public class UserCouponResponseDto {
 	private String discountPrice;
 	private Integer minOrderPrice;
 	private LocalDateTime expirationDate;
-	private String status;
+	private CouponStatus status;
 	private LocalDateTime useDate;
 }

src/main/java/com/threestar/trainus/domain/coupon/user/entity/Coupon.java

@@ -35,6 +35,7 @@ public class Coupon extends BaseDateEntity {
 	@GeneratedValue(strategy = GenerationType.IDENTITY)
 	private Long id;
 
+	@Builder.Default
 	@OneToMany(mappedBy = "coupon")
 	private List<UserCoupon> userCoupons = new ArrayList<>();
 

src/main/java/com/threestar/trainus/domain/coupon/user/entity/UserCoupon.java

@@ -17,7 +17,6 @@
 import jakarta.persistence.UniqueConstraint;
 import lombok.AccessLevel;
 import lombok.AllArgsConstructor;
-import lombok.Builder;
 import lombok.Getter;
 import lombok.NoArgsConstructor;
 
@@ -29,7 +28,6 @@
 	}
 )
 @Getter
-@Builder
 @AllArgsConstructor
 @NoArgsConstructor(access = AccessLevel.PROTECTED)
 public class UserCoupon extends BaseDateEntity {

src/main/java/com/threestar/trainus/domain/coupon/user/mapper/CouponMapper.java

@@ -17,7 +17,7 @@ public static CouponResponseDto toDto(Coupon coupon, boolean owned) {
 			.expirationDate(coupon.getExpirationDate())
 			.ownedStatus(owned ? OwnedStatus.OWNED : OwnedStatus.NOT_OWNED)
 			.quantity(coupon.getQuantity())
-			.category(coupon.getCategory().name())
+			.category(coupon.getCategory())
 			.openTime(coupon.getOpenAt())
 			.build();
 	}

src/main/java/com/threestar/trainus/domain/coupon/user/mapper/UserCouponMapper.java

@@ -18,7 +18,7 @@ public static CreateUserCouponResponseDto toCreateUserCouponResponseDto(UserCoup
 			.userId(userCoupon.getUser().getId())
 			.createdAt(userCoupon.getCreatedAt())
 			.expirationDate(userCoupon.getExpirationDate())
-			.status(userCoupon.getStatus().name())
+			.status(userCoupon.getStatus())
 			.build();
 	}
 
@@ -30,7 +30,7 @@ public static UserCouponResponseDto toUserCouponResponseDto(UserCoupon userCoupo
 			.discountPrice(coupon.getDiscountPrice())
 			.minOrderPrice(coupon.getMinOrderPrice())
 			.expirationDate(coupon.getExpirationDate())
-			.status(coupon.getStatus().name())
+			.status(coupon.getStatus())
 			.useDate(userCoupon.getUseDate())
 			.build();
 	}

src/main/java/com/threestar/trainus/domain/coupon/user/repository/CouponRepository.java

@@ -19,7 +19,8 @@ public interface CouponRepository extends JpaRepository<Coupon, Long> {
 	@Query("""
 		SELECT new com.threestar.trainus.domain.coupon.user.dto.CouponResponseDto(
 			c.id, c.name, c.discountPrice, c.minOrderPrice, c.expirationDate,
-			CASE WHEN uc.id IS NOT NULL THEN "OWNED" ELSE "NOT_OWNED" END,
+			CASE WHEN uc.id IS NOT NULL THEN com.threestar.trainus.domain.coupon.user.entity.OwnedStatus.OWNED
+			ELSE com.threestar.trainus.domain.coupon.user.entity.OwnedStatus.NOT_OWNED END,
 			c.quantity, c.category, c.openAt
 		)
 		FROM Coupon c

src/main/java/com/threestar/trainus/domain/lesson/admin/controller/AdminLessonController.java

@@ -4,6 +4,7 @@
 import org.springframework.http.ResponseEntity;
 import org.springframework.web.bind.annotation.DeleteMapping;
 import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.ModelAttribute;
 import org.springframework.web.bind.annotation.PathVariable;
 import org.springframework.web.bind.annotation.PostMapping;
 import org.springframework.web.bind.annotation.RequestBody;
@@ -21,15 +22,14 @@
 import com.threestar.trainus.domain.lesson.admin.entity.ApplicationAction;
 import com.threestar.trainus.domain.lesson.admin.service.AdminLessonService;
 import com.threestar.trainus.global.annotation.LoginUser;
+import com.threestar.trainus.global.dto.PageRequestDto;
 import com.threestar.trainus.global.exception.domain.ErrorCode;
 import com.threestar.trainus.global.exception.handler.BusinessException;
 import com.threestar.trainus.global.unit.BaseResponse;
 
 import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.tags.Tag;
 import jakarta.validation.Valid;
-import jakarta.validation.constraints.Max;
-import jakarta.validation.constraints.Min;
 import lombok.RequiredArgsConstructor;
 
 /**
@@ -71,16 +71,13 @@ public ResponseEntity<BaseResponse<Void>> deleteLesson(
 	@Operation(summary = "레슨 신청자 목록 조회 api", description = "레슨 신청자의 목록을 조회 가능함.")
 	public ResponseEntity<BaseResponse<LessonApplicationListResponseDto>> getLessonApplications(
 		@PathVariable Long lessonId,
-		@RequestParam(defaultValue = "1") @Min(value = 1, message = "페이지는 1 이상이어야 합니다.")
-		@Max(value = 1000, message = "페이지는 1000 이하여야 합니다.") int page,
-		@RequestParam(defaultValue = "5") @Min(value = 1, message = "limit는 1 이상이어야 합니다.")
-		@Max(value = 100, message = "limit는 100 이하여야 합니다.") int limit,
+		@Valid @ModelAttribute PageRequestDto pageRequestDto,
 		@RequestParam(defaultValue = "ALL") String status,
 		@LoginUser Long loginUserId) {
 
 		// 신청자 목록 조회
 		LessonApplicationListResponseDto responseDto = adminLessonService
-			.getLessonApplications(lessonId, page, limit, status, loginUserId);
+			.getLessonApplications(lessonId, pageRequestDto.getPage(), pageRequestDto.getLimit(), status, loginUserId);
 
 		return BaseResponse.ok("레슨 신청자 목록 조회 완료.", responseDto, HttpStatus.OK);
 	}
@@ -106,15 +103,12 @@ public ResponseEntity<BaseResponse<ApplicationProcessResponseDto>> processLesson
 	@Operation(summary = "레슨 참가자 목록 조회 api", description = "")
 	public ResponseEntity<BaseResponse<ParticipantListResponseDto>> getLessonParticipants(
 		@PathVariable Long lessonId,
-		@RequestParam(defaultValue = "1") @Min(value = 1, message = "페이지는 1 이상이어야 합니다.")
-		@Max(value = 1000, message = "페이지는 1000 이하여야 합니다.") int page,
-		@RequestParam(defaultValue = "5") @Min(value = 1, message = "limit는 1 이상이어야 합니다.")
-		@Max(value = 100, message = "limit는 100 이하여야 합니다.") int limit,
+		@Valid @ModelAttribute PageRequestDto pageRequestDto,
 		@LoginUser Long loginUserId) {
 
 		// 참가자 목록 조회
 		ParticipantListResponseDto responseDto = adminLessonService
-			.getLessonParticipants(lessonId, page, limit, loginUserId);
+			.getLessonParticipants(lessonId, pageRequestDto.getPage(), pageRequestDto.getLimit(), loginUserId);
 
 		return BaseResponse.ok("레슨 참가자 목록 조회 완료.", responseDto, HttpStatus.OK);
 	}
@@ -124,10 +118,7 @@ public ResponseEntity<BaseResponse<ParticipantListResponseDto>> getLessonPartici
 	@Operation(summary = "강사가 개설한 레슨 목록 조회 api", description = "")
 	public ResponseEntity<BaseResponse<CreatedLessonListResponseDto>> getCreatedLessons(
 		@PathVariable Long userId,
-		@RequestParam(defaultValue = "1") @Min(value = 1, message = "페이지는 1 이상이어야 합니다.")
-		@Max(value = 1000, message = "페이지는 1000 이하여야 합니다.") int page,
-		@RequestParam(defaultValue = "5") @Min(value = 1, message = "limit는 1 이상이어야 합니다.")
-		@Max(value = 100, message = "limit는 100 이하여야 합니다.") int limit,
+		@Valid @ModelAttribute PageRequestDto pageRequestDto,
 		@RequestParam(required = false) String status,
 		@LoginUser Long loginUserId) {
 
@@ -138,7 +129,7 @@ public ResponseEntity<BaseResponse<CreatedLessonListResponseDto>> getCreatedLess
 
 		// 개설한 레슨 목록 조회
 		CreatedLessonListResponseDto responseDto = adminLessonService
-			.getCreatedLessons(userId, page, limit, status);
+			.getCreatedLessons(userId, pageRequestDto.getPage(), pageRequestDto.getLimit(), status);
 
 		return BaseResponse.ok("개설한 레슨 목록 조회 완료.", responseDto, HttpStatus.OK);
 	}

src/main/java/com/threestar/trainus/domain/lesson/admin/dto/CreatedLessonDto.java

@@ -2,6 +2,8 @@
 
 import java.time.LocalDateTime;
 
+import com.threestar.trainus.domain.lesson.admin.entity.LessonStatus;
+
 import lombok.Builder;
 
 /**
@@ -14,7 +16,7 @@ public record CreatedLessonDto(
 	Integer maxParticipants,
 	Integer currentParticipants,
 	Integer price,
-	String status,
+	LessonStatus status,
 	LocalDateTime startAt,
 	LocalDateTime endAt,
 	Boolean openRun,

src/main/java/com/threestar/trainus/domain/lesson/admin/dto/LessonResponseDto.java

@@ -4,6 +4,7 @@
 import java.util.List;
 
 import com.threestar.trainus.domain.lesson.admin.entity.Category;
+import com.threestar.trainus.domain.lesson.admin.entity.LessonStatus;
 
 import lombok.Builder;
 
@@ -24,7 +25,7 @@ public record LessonResponseDto(
 	String district,
 	String dong,
 	String addressDetail,
-	String status,
+	LessonStatus status,
 	LocalDateTime createdAt,
 	List<String> lessonImages
 ) {

src/main/java/com/threestar/trainus/domain/lesson/admin/mapper/CreatedLessonMapper.java

@@ -16,7 +16,7 @@ public static CreatedLessonDto toCreatedLessonDto(Lesson lesson) {
 			.maxParticipants(lesson.getMaxParticipants())
 			.currentParticipants(lesson.getParticipantCount())
 			.price(lesson.getPrice())
-			.status(lesson.getStatus().name())
+			.status(lesson.getStatus())
 			.startAt(lesson.getStartAt())
 			.endAt(lesson.getEndAt())
 			.openRun(lesson.getOpenRun())

src/main/java/com/threestar/trainus/domain/lesson/admin/mapper/LessonMapper.java

@@ -55,7 +55,7 @@ public static LessonResponseDto toResponseDto(Lesson lesson, List<LessonImage> l
 			.district(lesson.getDistrict())
 			.dong(lesson.getDong())
 			.addressDetail(lesson.getAddressDetail())
-			.status(lesson.getStatus().name()) // enum이름 반환
+			.status(lesson.getStatus())
 			.createdAt(lesson.getCreatedAt())
 			.lessonImages(imageUrls) // 이미지 URL 목록
 			.build();
@@ -80,11 +80,11 @@ public static LessonDetailResponseDto toLessonDetailDto(
 			.profileImage(profile.getProfileImage())
 			.reviewCount(reviewCount)
 			.rating(rating)
-			.category(lesson.getCategory().name())
+			.category(lesson.getCategory())
 			.price(lesson.getPrice())
 			.maxParticipants(lesson.getMaxParticipants())
 			.currentParticipants(lesson.getParticipantCount())
-			.status(lesson.getStatus().name())
+			.status(lesson.getStatus())
 			.startAt(lesson.getStartAt())
 			.endAt(lesson.getEndAt())
 			.openTime(lesson.getOpenTime())

src/main/java/com/threestar/trainus/domain/lesson/admin/repository/LessonImageRepository.java

@@ -10,6 +10,7 @@
 public interface LessonImageRepository extends JpaRepository<LessonImage, Long> {
 
 	List<LessonImage> findByLesson(Lesson lesson);
+
 	List<LessonImage> findAllByLessonId(Long id);
 }
 

src/main/java/com/threestar/trainus/domain/lesson/admin/service/AdminLessonService.java

@@ -53,9 +53,7 @@ public class AdminLessonService {
 	// 새로운 레슨을 생성하는 메서드
 	public LessonResponseDto createLesson(LessonCreateRequestDto requestDto, Long userId) {
 		// User 조회
-		//TODO: 공통메소드
-		User user = userRepository.findById(userId)
-			.orElseThrow(() -> new BusinessException(ErrorCode.USER_NOT_FOUND));
+		User user = userService.getUserById(userId);
 
 		validateLessonTimes(requestDto.startAt(), requestDto.endAt());
 
@@ -119,10 +117,7 @@ private List<LessonImage> saveLessonImages(Lesson lesson, List<String> imageUrls
 	@Transactional
 	public void deleteLesson(Long lessonId, Long userId) {
 		// User 존재 확인
-		//TODO: 공통메소드
-		User user = userRepository.findById(userId)
-			.orElseThrow(() -> new BusinessException(ErrorCode.USER_NOT_FOUND));
-
+		User user = userService.getUserById(userId);
 		//레슨 조회
 		Lesson lesson = findLessonById(lessonId);