[JDBC 라이브러리 구현하기 - 3,4단계] 에코(조은찬) 미션 제출합니다. (#548)

* refactor: update에 가변인자를 받는 메서드 추가 및 try-with-resources 사용

* refactor: Callback과 ResultSetExtractor을 이용해 try-with-resources 구문 분리

* feat: Transaction 경계 구현

* refactor: 서비스에서 트랜젝션 구현을 위해 Connection 파라미터 추가

* feat: TransactionSynchronizationManager 및 DataSourceUtils 사용

* refactor: DataSourceUtils 사용으로 불필요한 Connection parameter 제거

* refactor: 트랜젝션 서비스 추상화

* refactor: 리뷰 반영

* refactor: 불필요한 getConnection 메서드 제거

* refactor: JdbcTemplate 메서드 정리

* refactor: 인프라 코드 제거

* fix: UserService 수정

app/src/main/java/com/techcourse/dao/UserDao.java

@@ -46,20 +46,18 @@ public void update(final User user) {
 
     public List<User> findAll() {
         final String sql = "select id, account, password, email from users";
-        return jdbcTemplate.query(sql, USER_ROW_MAPPER);
+        return jdbcTemplate.queryForList(sql, USER_ROW_MAPPER);
     }
 
     public User findById(final Long id) {
         final var sql = "select id, account, password, email from users where id = ?";
         final PreparedStatementSetter preparedStatementSetter = pstmt -> pstmt.setLong(1, id);
-        return jdbcTemplate.query(sql, USER_ROW_MAPPER, preparedStatementSetter);
-
+        return jdbcTemplate.queryForObject(sql, USER_ROW_MAPPER, preparedStatementSetter);
     }
 
 
     public User findByAccount(final String account) {
         final var sql = "select id, account, password, email from users where account = ?";
-        final PreparedStatementSetter preparedStatementSetter = pstmt -> pstmt.setString(1, account);
-        return jdbcTemplate.query(sql, USER_ROW_MAPPER, preparedStatementSetter);
+        return jdbcTemplate.queryForObject(sql, USER_ROW_MAPPER, account);
     }
 }

app/src/main/java/com/techcourse/dao/UserHistoryDao.java

@@ -1,62 +1,29 @@
 package com.techcourse.dao;
 
 import com.techcourse.domain.UserHistory;
-import org.springframework.jdbc.core.JdbcTemplate;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
-
-import javax.sql.DataSource;
-import java.sql.Connection;
-import java.sql.PreparedStatement;
-import java.sql.SQLException;
+import org.springframework.jdbc.core.JdbcTemplate;
 
 public class UserHistoryDao {
 
     private static final Logger log = LoggerFactory.getLogger(UserHistoryDao.class);
 
-    private final DataSource dataSource;
-
-    public UserHistoryDao(final DataSource dataSource) {
-        this.dataSource = dataSource;
-    }
+    private final JdbcTemplate jdbcTemplate;
 
     public UserHistoryDao(final JdbcTemplate jdbcTemplate) {
-        this.dataSource = null;
+        this.jdbcTemplate = jdbcTemplate;
     }
 
     public void log(final UserHistory userHistory) {
-        final var sql = "insert into user_history (user_id, account, password, email, created_at, created_by) values (?, ?, ?, ?, ?, ?)";
-
-        Connection conn = null;
-        PreparedStatement pstmt = null;
-        try {
-            conn = dataSource.getConnection();
-            pstmt = conn.prepareStatement(sql);
-
-            log.debug("query : {}", sql);
-
+        final String sql = "insert into user_history (user_id, account, password, email, created_at, created_by) values (?, ?, ?, ?, ?, ?)";
+        jdbcTemplate.update(sql, pstmt -> {
             pstmt.setLong(1, userHistory.getUserId());
             pstmt.setString(2, userHistory.getAccount());
             pstmt.setString(3, userHistory.getPassword());
             pstmt.setString(4, userHistory.getEmail());
             pstmt.setObject(5, userHistory.getCreatedAt());
             pstmt.setString(6, userHistory.getCreateBy());
-            pstmt.executeUpdate();
-        } catch (SQLException e) {
-            log.error(e.getMessage(), e);
-            throw new RuntimeException(e);
-        } finally {
-            try {
-                if (pstmt != null) {
-                    pstmt.close();
-                }
-            } catch (SQLException ignored) {}
-
-            try {
-                if (conn != null) {
-                    conn.close();
-                }
-            } catch (SQLException ignored) {}
-        }
+        });
     }
 }

app/src/main/java/com/techcourse/service/AppUserService.java

@@ -0,0 +1,36 @@
+package com.techcourse.service;
+
+import com.techcourse.dao.UserDao;
+import com.techcourse.dao.UserHistoryDao;
+import com.techcourse.domain.User;
+import com.techcourse.domain.UserHistory;
+import org.springframework.dao.DataAccessException;
+
+public class AppUserService implements UserService {
+
+    private final UserDao userDao;
+    private final UserHistoryDao userHistoryDao;
+
+    public AppUserService(final UserDao userDao, final UserHistoryDao userHistoryDao) {
+        this.userDao = userDao;
+        this.userHistoryDao = userHistoryDao;
+    }
+
+    @Override
+    public void insert(final User user) {
+        userDao.insert(user);
+    }
+
+    @Override
+    public void changePassword(final long id, final String newPassword, final String createBy) throws DataAccessException {
+        final var user = findById(id);
+        user.changePassword(newPassword);
+        userDao.update(user);
+        userHistoryDao.log(new UserHistory(user, createBy));
+    }
+
+    @Override
+    public User findById(final long id) {
+        return userDao.findById(id);
+    }
+}

app/src/main/java/com/techcourse/service/TxUserService.java

@@ -0,0 +1,46 @@
+package com.techcourse.service;
+
+import com.techcourse.config.DataSourceConfig;
+import com.techcourse.domain.User;
+import org.springframework.dao.DataAccessException;
+import org.springframework.jdbc.datasource.DataSourceUtils;
+
+import java.sql.Connection;
+import java.sql.SQLException;
+
+public class TxUserService implements UserService {
+    private final UserService userService;
+
+    public TxUserService(final UserService userService) {
+        this.userService = userService;
+    }
+
+    @Override
+    public User findById(final long id) {
+        return userService.findById(id);
+    }
+
+    @Override
+    public void insert(final User user) {
+        userService.insert(user);
+    }
+
+    @Override
+    public void changePassword(final long id, final String newPassword, final String createBy) {
+        final Connection connection = DataSourceUtils.getConnection(DataSourceConfig.getInstance());
+        try {
+            connection.setAutoCommit(false);
+            userService.changePassword(id, newPassword, createBy);
+            connection.commit();
+        } catch (final Exception e) {
+            try {
+                connection.rollback();
+            } catch (SQLException ex) {
+                throw new DataAccessException(ex);
+            }
+            throw new DataAccessException(e);
+        } finally {
+            DataSourceUtils.releaseConnection(connection, DataSourceConfig.getInstance());
+        }
+    }
+}

app/src/main/java/com/techcourse/service/UserService.java

@@ -1,32 +1,11 @@
 package com.techcourse.service;
 
-import com.techcourse.dao.UserDao;
-import com.techcourse.dao.UserHistoryDao;
 import com.techcourse.domain.User;
-import com.techcourse.domain.UserHistory;
 
-public class UserService {
+public interface UserService {
+    User findById(final long id);
 
-    private final UserDao userDao;
-    private final UserHistoryDao userHistoryDao;
+    void insert(User user);
 
-    public UserService(final UserDao userDao, final UserHistoryDao userHistoryDao) {
-        this.userDao = userDao;
-        this.userHistoryDao = userHistoryDao;
-    }
-
-    public User findById(final long id) {
-        return userDao.findById(id);
-    }
-
-    public void insert(final User user) {
-        userDao.insert(user);
-    }
-
-    public void changePassword(final long id, final String newPassword, final String createBy) {
-        final var user = findById(id);
-        user.changePassword(newPassword);
-        userDao.update(user);
-        userHistoryDao.log(new UserHistory(user, createBy));
-    }
+    void changePassword(long id, String newPassword, String createBy);
 }

app/src/test/java/com/techcourse/dao/UserDaoTest.java

@@ -11,13 +11,13 @@
 
 class UserDaoTest {
 
+    private final JdbcTemplate jdbcTemplate = new JdbcTemplate(DataSourceConfig.getInstance());
     private UserDao userDao;
 
     @BeforeEach
     void setup() {
         DatabasePopulatorUtils.execute(DataSourceConfig.getInstance());
-
-        userDao = new UserDao(new JdbcTemplate(DataSourceConfig.getInstance()));
+        userDao = new UserDao(jdbcTemplate);
         final var user = new User("gugu", "password", "[email protected]");
         userDao.insert(user);
     }

app/src/test/java/com/techcourse/service/UserServiceTest.java → app/src/test/java/com/techcourse/service/AppUserServiceTest.java

@@ -5,17 +5,15 @@
 import com.techcourse.dao.UserHistoryDao;
 import com.techcourse.domain.User;
 import com.techcourse.support.jdbc.init.DatabasePopulatorUtils;
-import org.springframework.dao.DataAccessException;
-import org.springframework.jdbc.core.JdbcTemplate;
 import org.junit.jupiter.api.BeforeEach;
-import org.junit.jupiter.api.Disabled;
 import org.junit.jupiter.api.Test;
+import org.springframework.dao.DataAccessException;
+import org.springframework.jdbc.core.JdbcTemplate;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.junit.jupiter.api.Assertions.assertThrows;
 
-@Disabled
-class UserServiceTest {
+class AppUserServiceTest {
 
     private JdbcTemplate jdbcTemplate;
     private UserDao userDao;
@@ -33,7 +31,7 @@ void setUp() {
     @Test
     void testChangePassword() {
         final var userHistoryDao = new UserHistoryDao(jdbcTemplate);
-        final var userService = new UserService(userDao, userHistoryDao);
+        final var userService = new AppUserService(userDao, userHistoryDao);
 
         final var newPassword = "qqqqq";
         final var createBy = "gugu";
@@ -48,7 +46,10 @@ void testChangePassword() {
     void testTransactionRollback() {
         // 트랜잭션 롤백 테스트를 위해 mock으로 교체
         final var userHistoryDao = new MockUserHistoryDao(jdbcTemplate);
-        final var userService = new UserService(userDao, userHistoryDao);
+        // 애플리케이션 서비스
+        final var appUserService = new AppUserService(userDao, userHistoryDao);
+        // 트랜잭션 서비스 추상화
+        final var userService = new TxUserService(appUserService);
 
         final var newPassword = "newPassword";
         final var createBy = "gugu";