[Fix] 재지원 플로우 지원 순번 저장 방식 수정

src/main/java/com/jobdri/jobdri_api/domain/mockapply/controller/MockApplyController.java

@@ -59,7 +59,7 @@ public ApiResponse<MockApplyHomeResponse> getMyMockApplies(
                     content = @Content(
                             mediaType = "application/json",
                             schema = @Schema(implementation = ApiResponse.class),
-                            examples = @ExampleObject(value = "{\"isSuccess\":true,\"code\":\"COMMON2000\",\"message\":\"모의 서류 지원이 생성되었습니다.\",\"result\":{\"jobPostingId\":1,\"mockApplyId\":10,\"applyType\":\"ACTUAL\"},\"error\":null}")
+                            examples = @ExampleObject(value = "{\"isSuccess\":true,\"code\":\"COMMON2000\",\"message\":\"모의 서류 지원이 생성되었습니다.\",\"result\":{\"jobPostingId\":1,\"mockApplyId\":10,\"applyType\":\"ACTUAL\",\"sequence\":1},\"error\":null}")
                     )
             ),
             @io.swagger.v3.oas.annotations.responses.ApiResponse(
@@ -88,7 +88,7 @@ public ApiResponse<MockApplyCreateResponse> createActualApply(
     ) {
         return ApiResponse.onSuccess(
                 "모의 서류 지원이 생성되었습니다.",
-                mockApplyService.createActualApply(userDetails.getUser(), request.jobPostingId())
+                mockApplyService.createActualApply(userDetails.getUser(), request.jobPostingId(), request.sequence())
         );
     }
 
@@ -103,7 +103,7 @@ public ApiResponse<MockApplyCreateResponse> createActualApply(
                     content = @Content(
                             mediaType = "application/json",
                             schema = @Schema(implementation = ApiResponse.class),
-                            examples = @ExampleObject(value = "{\"isSuccess\":true,\"code\":\"COMMON2000\",\"message\":\"모의 서류 지원이 생성되었습니다.\",\"result\":{\"jobPostingId\":1,\"mockApplyId\":10,\"applyType\":\"MOCK\"},\"error\":null}")
+                            examples = @ExampleObject(value = "{\"isSuccess\":true,\"code\":\"COMMON2000\",\"message\":\"모의 서류 지원이 생성되었습니다.\",\"result\":{\"jobPostingId\":1,\"mockApplyId\":10,\"applyType\":\"MOCK\",\"sequence\":1},\"error\":null}")
                     )
             ),
             @io.swagger.v3.oas.annotations.responses.ApiResponse(
@@ -132,7 +132,11 @@ public ApiResponse<MockApplyCreateResponse> createMockApplyFromJobPosting(
     ) {
         return ApiResponse.onSuccess(
                 "모의 서류 지원이 생성되었습니다.",
-                mockApplyService.createMockApplyFromJobPosting(userDetails.getUser(), request.jobPostingId())
+                mockApplyService.createMockApplyFromJobPosting(
+                        userDetails.getUser(),
+                        request.jobPostingId(),
+                        request.sequence()
+                )
         );
     }
 
@@ -147,7 +151,7 @@ public ApiResponse<MockApplyCreateResponse> createMockApplyFromJobPosting(
                     content = @Content(
                             mediaType = "application/json",
                             schema = @Schema(implementation = ApiResponse.class),
-                            examples = @ExampleObject(value = "{\"isSuccess\":true,\"code\":\"COMMON2000\",\"message\":\"모의 서류 지원이 생성되었습니다.\",\"result\":{\"jobPostingId\":1,\"mockApplyId\":10,\"applyType\":\"MOCK\"},\"error\":null}")
+                            examples = @ExampleObject(value = "{\"isSuccess\":true,\"code\":\"COMMON2000\",\"message\":\"모의 서류 지원이 생성되었습니다.\",\"result\":{\"jobPostingId\":1,\"mockApplyId\":10,\"applyType\":\"MOCK\",\"sequence\":1},\"error\":null}")
                     )
             ),
             @io.swagger.v3.oas.annotations.responses.ApiResponse(

src/main/java/com/jobdri/jobdri_api/domain/mockapply/dto/request/MockApplyCreateActualRequest.java

@@ -1,9 +1,16 @@
 package com.jobdri.jobdri_api.domain.mockapply.dto.request;
 
 import jakarta.validation.constraints.NotNull;
+import jakarta.validation.constraints.Positive;
 
 public record MockApplyCreateActualRequest(
         @NotNull(message = "공고 ID는 필수입니다.")
-        Long jobPostingId
+        Long jobPostingId,
+
+        @Positive(message = "지원 순번은 1 이상이어야 합니다.")
+        Integer sequence
 ) {
+    public MockApplyCreateActualRequest(Long jobPostingId) {
+        this(jobPostingId, null);
+    }
 }

src/main/java/com/jobdri/jobdri_api/domain/mockapply/dto/request/MockApplyCreateMockFromJobPostingRequest.java

@@ -1,9 +1,16 @@
 package com.jobdri.jobdri_api.domain.mockapply.dto.request;
 
 import jakarta.validation.constraints.NotNull;
+import jakarta.validation.constraints.Positive;
 
 public record MockApplyCreateMockFromJobPostingRequest(
         @NotNull(message = "공고 ID는 필수입니다.")
-        Long jobPostingId
+        Long jobPostingId,
+
+        @Positive(message = "지원 순번은 1 이상이어야 합니다.")
+        Integer sequence
 ) {
+    public MockApplyCreateMockFromJobPostingRequest(Long jobPostingId) {
+        this(jobPostingId, null);
+    }
 }

src/main/java/com/jobdri/jobdri_api/domain/mockapply/dto/request/MockApplyCreateMockRequest.java

@@ -2,6 +2,7 @@
 
 import com.jobdri.jobdri_api.domain.jobposting.dto.request.JobPostingMockGenerateRequest;
 import jakarta.validation.constraints.NotNull;
+import jakarta.validation.constraints.Positive;
 
 public record MockApplyCreateMockRequest(
         @NotNull(message = "회사 ID는 필수입니다.")
@@ -11,8 +12,15 @@ public record MockApplyCreateMockRequest(
         Long middleClassificationId,
 
         @NotNull(message = "소분류 ID는 필수입니다.")
-        Long detailClassificationId
+        Long detailClassificationId,
+
+        @Positive(message = "지원 순번은 1 이상이어야 합니다.")
+        Integer sequence
 ) {
+    public MockApplyCreateMockRequest(Long companyId, Long middleClassificationId, Long detailClassificationId) {
+        this(companyId, middleClassificationId, detailClassificationId, null);
+    }
+
     public JobPostingMockGenerateRequest toJobPostingMockGenerateRequest() {
         return new JobPostingMockGenerateRequest(companyId, middleClassificationId, detailClassificationId);
     }

src/main/java/com/jobdri/jobdri_api/domain/mockapply/dto/response/MockApplyCreateResponse.java

@@ -6,13 +6,15 @@
 public record MockApplyCreateResponse(
         Long jobPostingId,
         Long mockApplyId,
-        ApplyType applyType
+        ApplyType applyType,
+        int sequence
 ) {
     public static MockApplyCreateResponse from(MockApply mockApply) {
         return new MockApplyCreateResponse(
                 mockApply.getJobPosting().getId(),
                 mockApply.getId(),
-                mockApply.getApplyType()
+                mockApply.getApplyType(),
+                mockApply.getSequence()
         );
     }
 }

src/main/java/com/jobdri/jobdri_api/domain/mockapply/entity/MockApply.java

@@ -16,7 +16,13 @@
 @NoArgsConstructor(access = AccessLevel.PROTECTED)
 @AllArgsConstructor(access = AccessLevel.PRIVATE)
 @Builder(access = AccessLevel.PRIVATE)
-@Table(name = "mock_applies")
+@Table(
+        name = "mock_applies",
+        uniqueConstraints = @UniqueConstraint(
+                name = "uk_mock_apply_user_posting_sequence",
+                columnNames = {"user_id", "job_posting_id", "sequence"}
+        )
+)
 public class MockApply {
 
     @Id
@@ -39,6 +45,8 @@ public class MockApply {
     @Column(nullable = false)
     private MockApplyStatus status;
 
+    private Integer sequence;
+
     @Column(nullable = false)
     private LocalDateTime createdAt;
 
@@ -50,11 +58,16 @@ public class MockApply {
     private List<Question> questions = new ArrayList<>();
 
     public static MockApply create(User user, JobPosting jobPosting, ApplyType applyType) {
+        return create(user, jobPosting, applyType, null);
+    }
+
+    public static MockApply create(User user, JobPosting jobPosting, ApplyType applyType, Integer sequence) {
         return MockApply.builder()
                 .user(user)
                 .jobPosting(jobPosting)
                 .applyType(applyType)
                 .status(MockApplyStatus.APPLICATION_CREATED)
+                .sequence(sequence)
                 .createdAt(LocalDateTime.now())
                 .build();
     }

src/main/java/com/jobdri/jobdri_api/domain/mockapply/repository/MockApplyRepository.java

@@ -13,6 +13,10 @@ public interface MockApplyRepository extends JpaRepository<MockApply, Long> {
     long countByUserIdAndJobPostingId(Long userId, Long jobPostingId);
 
     default int calculateSequence(MockApply mockApply) {
+        if (mockApply.getSequence() != null && mockApply.getSequence() > 0) {
+            return mockApply.getSequence();
+        }
+
         return Math.toIntExact(countSequenceByUserIdAndJobPostingId(
                 mockApply.getUser().getId(),
                 mockApply.getJobPosting().getId(),

src/main/java/com/jobdri/jobdri_api/domain/mockapply/service/MockApplyPersistenceService.java

@@ -0,0 +1,20 @@
+package com.jobdri.jobdri_api.domain.mockapply.service;
+
+import com.jobdri.jobdri_api.domain.mockapply.entity.MockApply;
+import com.jobdri.jobdri_api.domain.mockapply.repository.MockApplyRepository;
+import lombok.RequiredArgsConstructor;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Propagation;
+import org.springframework.transaction.annotation.Transactional;
+
+@Service
+@RequiredArgsConstructor
+public class MockApplyPersistenceService {
+
+    private final MockApplyRepository mockApplyRepository;
+
+    @Transactional(propagation = Propagation.REQUIRES_NEW)
+    public MockApply saveAndFlush(MockApply mockApply) {
+        return mockApplyRepository.saveAndFlush(mockApply);
+    }
+}

src/main/java/com/jobdri/jobdri_api/domain/mockapply/service/MockApplyService.java

@@ -25,44 +25,75 @@
 import com.jobdri.jobdri_api.global.apiPayload.code.GeneralErrorCode;
 import com.jobdri.jobdri_api.global.apiPayload.exception.GeneralException;
 import lombok.RequiredArgsConstructor;
+import org.springframework.dao.DataIntegrityViolationException;
 import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Propagation;
 import org.springframework.transaction.annotation.Transactional;
 
+import java.sql.SQLException;
 import java.util.List;
+import java.util.Locale;
 import java.util.stream.Collectors;
 
 @Service
 @RequiredArgsConstructor
 @Transactional(readOnly = true)
 public class MockApplyService {
+    private static final int SEQUENCE_SAVE_MAX_RETRY = 5;
+    private static final String SEQUENCE_UNIQUE_CONSTRAINT = "uk_mock_apply_user_posting_sequence";
+    private static final String UNIQUE_VIOLATION_SQL_STATE = "23505";
+
     private final MockApplyRepository mockApplyRepository;
     private final JobPostingRepository jobPostingRepository;
     private final CompanyRepository companyRepository;
     private final MockJobPostingGenerationService mockJobPostingGenerationService;
     private final JobPostingService jobPostingService;
     private final UserService userService;
+    private final MockApplyPersistenceService mockApplyPersistenceService;
 
-    @Transactional
+    @Transactional(propagation = Propagation.NOT_SUPPORTED)
     @AuditLogEvent(action = "MOCK_APPLY_CREATE", targetType = "MOCK_APPLY", targetId = "#result.mockApplyId()")
     public MockApplyCreateResponse createActualApply(User user, Long jobPostingId) {
+        return createActualApply(user, jobPostingId, null);
+    }
+
+    @Transactional(propagation = Propagation.NOT_SUPPORTED)
+    @AuditLogEvent(action = "MOCK_APPLY_CREATE", targetType = "MOCK_APPLY", targetId = "#result.mockApplyId()")
+    public MockApplyCreateResponse createActualApply(User user, Long jobPostingId, Integer sequence) {
         User validatedUser = userService.validateUser(user);
         JobPosting jobPosting = jobPostingService.getOwnedJobPosting(validatedUser, jobPostingId);
 
-        MockApply mockApply = MockApply.create(validatedUser, jobPosting, ApplyType.ACTUAL);
-        return MockApplyCreateResponse.from(mockApplyRepository.save(mockApply));
+        MockApply mockApply = saveMockApplyWithSequence(
+                validatedUser,
+                jobPosting,
+                ApplyType.ACTUAL,
+                sequence
+        );
+        return MockApplyCreateResponse.from(mockApply);
     }
 
-    @Transactional
+    @Transactional(propagation = Propagation.NOT_SUPPORTED)
     @AuditLogEvent(action = "MOCK_APPLY_CREATE", targetType = "MOCK_APPLY", targetId = "#result.mockApplyId()")
     public MockApplyCreateResponse createMockApplyFromJobPosting(User user, Long jobPostingId) {
+        return createMockApplyFromJobPosting(user, jobPostingId, null);
+    }
+
+    @Transactional(propagation = Propagation.NOT_SUPPORTED)
+    @AuditLogEvent(action = "MOCK_APPLY_CREATE", targetType = "MOCK_APPLY", targetId = "#result.mockApplyId()")
+    public MockApplyCreateResponse createMockApplyFromJobPosting(User user, Long jobPostingId, Integer sequence) {
         User validatedUser = userService.validateUser(user);
         JobPosting jobPosting = jobPostingService.getOwnedJobPosting(validatedUser, jobPostingId);
 
-        MockApply mockApply = MockApply.create(validatedUser, jobPosting, ApplyType.MOCK);
-        return MockApplyCreateResponse.from(mockApplyRepository.save(mockApply));
+        MockApply mockApply = saveMockApplyWithSequence(
+                validatedUser,
+                jobPosting,
+                ApplyType.MOCK,
+                sequence
+        );
+        return MockApplyCreateResponse.from(mockApply);
     }
 
-    @Transactional
+    @Transactional(propagation = Propagation.NOT_SUPPORTED)
     @AuditLogEvent(action = "MOCK_APPLY_CREATE", targetType = "MOCK_APPLY", targetId = "#result.mockApplyId()")
     public MockApplyCreateResponse createMockApply(User user, MockApplyCreateMockRequest request) {
         User validatedUser = userService.validateUser(user);
@@ -90,8 +121,13 @@ public MockApplyCreateResponse createMockApply(User user, MockApplyCreateMockReq
                         "생성된 모의 공고를 찾을 수 없습니다. jobPostingId=" + savedJobPostingId
                 ));
 
-        MockApply mockApply = MockApply.create(validatedUser, savedJobPosting, ApplyType.MOCK);
-        return MockApplyCreateResponse.from(mockApplyRepository.save(mockApply));
+        MockApply mockApply = saveMockApplyWithSequence(
+                validatedUser,
+                savedJobPosting,
+                ApplyType.MOCK,
+                request.sequence()
+        );
+        return MockApplyCreateResponse.from(mockApply);
     }
 
     public JobPostingResponse getMockApplyJobPosting(User user, Long mockApplyId) {
@@ -109,8 +145,9 @@ public MockApplySequenceResponse getMockApplySequence(User user, Long mockApplyI
                 mockApplyRepository.countByUserIdAndJobPostingId(validatedUser.getId(), jobPostingId)
         );
         int sequence = mockApplyRepository.calculateSequence(mockApply);
+        totalCount = Math.max(totalCount, sequence);
 
-        if (sequence < 1 || sequence > totalCount) {
+        if (sequence < 1) {
             throw new GeneralException(
                     GeneralErrorCode.MOCK_APPLY_NOT_FOUND,
                     "해당 공고에 연결된 모의 서류 지원 순서를 찾을 수 없습니다. mockApplyId=" + mockApplyId
@@ -159,4 +196,77 @@ private MockApply getOwnedMockApply(User user, Long mockApplyId) {
 
         return mockApply;
     }
+
+    private int resolveSequence(User user, JobPosting jobPosting, Integer requestedSequence) {
+        if (isPositiveSequence(requestedSequence)) {
+            return requestedSequence;
+        }
+        return Math.toIntExact(mockApplyRepository.countByUserIdAndJobPostingId(
+                user.getId(),
+                jobPosting.getId()
+        )) + 1;
+    }
+
+    private boolean isPositiveSequence(Integer sequence) {
+        return sequence != null && sequence > 0;
+    }
+
+    private MockApply saveMockApplyWithSequence(
+            User user,
+            JobPosting jobPosting,
+            ApplyType applyType,
+            Integer requestedSequence
+    ) {
+        int sequence = resolveSequence(user, jobPosting, requestedSequence);
+        for (int attempt = 0; attempt < SEQUENCE_SAVE_MAX_RETRY; attempt++) {
+            try {
+                return mockApplyPersistenceService.saveAndFlush(MockApply.create(user, jobPosting, applyType, sequence));
+            } catch (DataIntegrityViolationException e) {
+                if (!isSequenceUniqueConflict(e)) {
+                    throw e;
+                }
+                if (isPositiveSequence(requestedSequence)) {
+                    throw new GeneralException(
+                            GeneralErrorCode.INVALID_PARAMETER,
+                            "이미 사용 중인 지원 순번입니다. sequence=" + requestedSequence
+                    );
+                }
+                sequence++;
+            }
+        }
+
+        throw new GeneralException(
+            GeneralErrorCode.INTERNAL_SERVER_ERROR,
+            "모의 서류 지원 순번 생성에 실패했습니다."
+        );
+    }
+
+    private boolean isSequenceUniqueConflict(DataIntegrityViolationException exception) {
+        Throwable cause = exception;
+        while (cause != null) {
+            if (cause instanceof org.hibernate.exception.ConstraintViolationException constraintViolation
+                    && isSequenceConstraintName(constraintViolation.getConstraintName())) {
+                return true;
+            }
+            if (cause instanceof SQLException sqlException
+                    && UNIQUE_VIOLATION_SQL_STATE.equals(sqlException.getSQLState())
+                    && containsSequenceConstraint(sqlException.getMessage())) {
+                return true;
+            }
+            if (containsSequenceConstraint(cause.getMessage())) {
+                return true;
+            }
+            cause = cause.getCause();
+        }
+        return false;
+    }
+
+    private boolean isSequenceConstraintName(String constraintName) {
+        return containsSequenceConstraint(constraintName);
+    }
+
+    private boolean containsSequenceConstraint(String value) {
+        return value != null
+                && value.toLowerCase(Locale.ROOT).contains(SEQUENCE_UNIQUE_CONSTRAINT);
+    }
 }