generate unique account

build.gradle

@@ -24,12 +24,14 @@ repositories {
 dependencies {
     implementation 'org.springframework.boot:spring-boot-starter-data-jpa'
     implementation 'org.springframework.boot:spring-boot-starter-web'
+    implementation 'org.springframework.boot:spring-boot-starter-validation'
     compileOnly 'org.projectlombok:lombok'
     runtimeOnly 'com.mysql:mysql-connector-j'
     annotationProcessor 'org.projectlombok:lombok'
     testImplementation 'org.springframework.boot:spring-boot-starter-test'
     implementation 'io.springfox:springfox-boot-starter:3.0.0'
     implementation 'io.springfox:springfox-swagger-ui:3.0.0'
+
 }
 
 tasks.named('test') {

src/main/java/com/eum/bank/common/dto/request/AccountRequestDTO.java

@@ -0,0 +1,13 @@
+package com.eum.bank.common.dto.request;
+
+import jakarta.validation.constraints.NotEmpty;
+import lombok.Getter;
+
+public class AccountRequestDTO {
+    // 계좌 생성 요청
+    @Getter
+    public static class CreateAccount {
+        @NotEmpty(message = "비밀번호를 입력해주세요.")
+        private Long password;
+    }
+}

src/main/java/com/eum/bank/common/dto/response/AccountResponseDTO.java

@@ -0,0 +1,16 @@
+package com.eum.bank.common.dto.response;
+
+import jakarta.validation.constraints.NotEmpty;
+import lombok.Builder;
+import lombok.Getter;
+import lombok.Setter;
+
+public class AccountResponseDTO {
+    // 계좌 생성 응답
+    @Builder
+    @Getter
+    public static class Create {
+        @NotEmpty(message = "계좌 번호가 생성되어야 합니다.")
+        private String accountNumber;
+    }
+}

src/main/java/com/eum/bank/controller/AccountController.java

@@ -0,0 +1,28 @@
+package com.eum.bank.controller;
+
+import com.eum.bank.common.APIResponse;
+import com.eum.bank.common.dto.request.AccountRequestDTO;
+import com.eum.bank.common.dto.response.AccountResponseDTO;
+import com.eum.bank.common.enums.SuccessCode;
+import com.eum.bank.service.AccountService;
+import lombok.RequiredArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.*;
+
+@RestController
+@RequiredArgsConstructor
+@RequestMapping("/account")
+@Slf4j
+public class AccountController {
+    private final AccountService accountService;
+    @PostMapping("/create")
+    public ResponseEntity<?> create(@RequestBody AccountRequestDTO.CreateAccount createAccount) {
+
+        Long password = createAccount.getPassword();
+        APIResponse<?> response = accountService.createAccount(password);
+
+        return ResponseEntity.ok(response);
+    }
+}

src/main/java/com/eum/bank/exception/GlobalExceptionHandler.java

@@ -28,7 +28,6 @@
 public class GlobalExceptionHandler {
     private final HttpStatus HTTP_STATUS_OK = HttpStatus.OK;
 
-
     /**
      * [Exception] API 호출 시 '객체' 혹은 '파라미터' 데이터 값이 유효하지 않은 경우
      *

src/main/java/com/eum/bank/repository/AccountRepository.java

@@ -4,4 +4,6 @@
 import org.springframework.data.jpa.repository.JpaRepository;
 
 public interface AccountRepository extends JpaRepository<Account, String> {
+    Account save(Account account);
+    Boolean findByAccountNumber(String accountNumber);
 }

src/main/java/com/eum/bank/service/AccountService.java

@@ -0,0 +1,71 @@
+package com.eum.bank.service;
+
+import com.eum.bank.common.APIResponse;
+import com.eum.bank.common.dto.response.AccountResponseDTO;
+import com.eum.bank.common.enums.SuccessCode;
+import com.eum.bank.domain.account.entity.Account;
+import com.eum.bank.repository.AccountRepository;
+import lombok.RequiredArgsConstructor;
+import org.springframework.stereotype.Service;
+
+import java.util.Random;
+
+@Service
+@RequiredArgsConstructor
+public class AccountService {
+
+    private final AccountRepository accountRepository;
+
+    public APIResponse<?> createAccount(Long password) {
+
+        String accountNumber;
+        do {
+            accountNumber = generateAccountNumber();
+        }while (
+                validateAccountNumber(accountNumber)
+        );
+
+        Account account = Account.builder()
+                .accountNumber(accountNumber)
+                .password(password.toString())
+                .totalBudget(0L)
+                .availableBudget(0L)
+                .build();
+
+        accountRepository.save(account);
+
+        return APIResponse.of(SuccessCode.SELECT_SUCCESS, AccountResponseDTO.Create.builder()
+                .accountNumber(account.getAccountNumber())
+                .build());
+    }
+
+    public String generateAccountNumber() {
+        Random random = new Random();
+        StringBuilder uniqueNumber = new StringBuilder();
+
+        for (int i = 0; i < 12; i++) {
+            int digit = random.nextInt(10);
+            uniqueNumber.append(digit);
+        }
+
+        if( validateAccountNumber(uniqueNumber.toString()) )
+            generateAccountNumber();
+
+        return uniqueNumber.toString();
+    }
+    public Boolean validateAccountNumber(String accountNumber) {
+        if (accountNumber.length() != 12) {
+            return false;
+        }
+
+        try {
+            Long.parseLong(accountNumber);
+            accountRepository.findByAccountNumber(accountNumber);
+        } catch (NumberFormatException e) {
+            return false;
+        }
+        return true;
+    }
+
+
+}