[JDBC 라이브러리 구현 4단계] 메리(최승원) 미션 제출합니다

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

@@ -6,7 +6,6 @@
 import org.springframework.jdbc.core.JdbcTemplate;
 import org.springframework.jdbc.core.RowMapper;
 
-import java.sql.Connection;
 import java.sql.SQLException;
 import java.util.List;
 
@@ -27,50 +26,50 @@ public UserDao(final JdbcTemplate jdbcTemplate) {
         this.jdbcTemplate = jdbcTemplate;
     }
 
-    public int insert(final Connection connection, final User user) throws SQLException {
+    public int insert(final User user) throws SQLException {
         final var sql = "insert into users (account, password, email) values (?, ?, ?)";
         log.debug("query : {}", sql);
 
-        return updateQuery(connection, sql, user.getAccount(), user.getPassword(), user.getEmail());
+        return updateQuery(sql, user.getAccount(), user.getPassword(), user.getEmail());
     }
 
-    private int updateQuery(final Connection connection, final String sql, final Object... objects) throws SQLException {
-        final int updatedRows = jdbcTemplate.update(connection, sql, objects);
+    private int updateQuery(final String sql, final Object... objects) throws SQLException {
+        final int updatedRows = jdbcTemplate.update(sql, objects);
         if (updatedRows < 1) {
             throw new RuntimeException("저장된 데이터가 없습니다.");
         }
         return updatedRows;
     }
 
-    public int update(final Connection connection, final User user) throws SQLException {
+    public int update(final User user) throws SQLException {
         final var sql = "update users set (account, password, email) = (?, ?, ?)";
         log.debug("query : {}", sql);
 
-        return updateQuery(connection, sql, user.getAccount(), user.getPassword(), user.getEmail());
+        return updateQuery(sql, user.getAccount(), user.getPassword(), user.getEmail());
     }
 
-    public List<User> findAll(final Connection connection) throws SQLException {
+    public List<User> findAll() throws SQLException {
         final var sql = "select id, account, password, email from users";
-        final List<User> users = jdbcTemplate.query(connection, sql, userRowMapper);
+        final List<User> users = jdbcTemplate.query(sql, userRowMapper);
 
         log.debug("query : {}", sql);
 
         return users;
     }
 
-    public User findById(final Connection connection, final Long id) throws SQLException {
+    public User findById(final Long id) throws SQLException {
         final var sql = "select id, account, password, email from users where id = ?";
-        final User user = jdbcTemplate.queryForObject(connection, sql, userRowMapper, id)
+        final User user = jdbcTemplate.queryForObject(sql, userRowMapper, id)
                                       .orElseThrow(() -> new RuntimeException("찾는 사용자가 존재하지 않습니다."));
 
         log.debug("query : {}", sql);
 
         return user;
     }
 
-    public User findByAccount(final Connection connection, final String account) throws SQLException {
+    public User findByAccount(final String account) throws SQLException {
         final var sql = "select id, account, password, email from users where account = ?";
-        final User user = jdbcTemplate.queryForObject(connection, sql, userRowMapper, account)
+        final User user = jdbcTemplate.queryForObject(sql, userRowMapper, account)
                                       .orElseThrow(() -> new RuntimeException("찾는 사용자가 존재하지 않습니다."));
 
         log.debug("query : {}", sql);

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

@@ -5,7 +5,6 @@
 import org.slf4j.LoggerFactory;
 import org.springframework.jdbc.core.JdbcTemplate;
 
-import java.sql.Connection;
 import java.sql.SQLException;
 
 public class UserHistoryDao {
@@ -18,10 +17,9 @@ public UserHistoryDao(final JdbcTemplate jdbcTemplate) {
         this.jdbcTemplate = jdbcTemplate;
     }
 
-    public void log(final Connection connection, final UserHistory userHistory) throws SQLException {
+    public void log(final UserHistory userHistory) throws SQLException {
         final var sql = "insert into user_history (user_id, account, password, email, created_at, created_by) values (?, ?, ?, ?, ?, ?)";
         jdbcTemplate.update(
-                connection,
                 sql,
                 userHistory.getUserId(),
                 userHistory.getAccount(),

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

@@ -0,0 +1,37 @@
+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 java.sql.SQLException;
+
+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 User findById(final long id) throws SQLException {
+        return userDao.findById(id);
+    }
+
+    @Override
+    public void insert(final User user) throws SQLException {
+        userDao.insert(user);
+    }
+
+    @Override
+    public void changePassword(long id, final String newPassword, final String createBy) throws SQLException {
+        final var user = findById(id);
+        user.changePassword(newPassword);
+        userDao.update(user);
+        userHistoryDao.log(new UserHistory(user, createBy));
+    }
+}

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

@@ -0,0 +1,9 @@
+package com.techcourse.service;
+
+import java.sql.SQLException;
+
+@FunctionalInterface
+public interface TransactionCallback<T> {
+
+    T execute() throws SQLException;
+}

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

@@ -0,0 +1,65 @@
+package com.techcourse.service;
+
+import org.springframework.dao.DataAccessException;
+import org.springframework.jdbc.datasource.DataSourceUtils;
+import org.springframework.transaction.support.TransactionSynchronizationManager;
+
+import javax.sql.DataSource;
+import java.sql.Connection;
+import java.sql.SQLException;
+
+public class TransactionManager {
+
+    private final DataSource dataSource;
+
+    public TransactionManager(final DataSource dataSource) {
+        this.dataSource = dataSource;
+    }
+
+    public <T> T execute(final TransactionCallback<T> callback) {
+        try {
+            final Connection connection = TransactionSynchronizationManager.startNewTransaction(dataSource);
+
+            final T result = callback.execute();
+
+            commitTransaction(connection);
+            TransactionSynchronizationManager.finishTransaction(dataSource);
+
+            return result;
+        } catch (final SQLException ex) {
+            throw new RuntimeException("실행 중 예외가 발생했습니다.");
+        }
+    }
+
+    public static void commitTransaction(final Connection connection) {
+        try {
+            connection.commit();
+
+            clear(connection);
+        } catch (final SQLException ex) {
+            rollback(connection);
+
+            throw new DataAccessException("실행 중 예외가 발생했습니다.");
+        }
+    }
+
+    public static void rollback(final Connection connection) {
+        try {
+            connection.rollback();
+
+            clear(connection);
+        } catch (final SQLException ex) {
+            throw new DataAccessException("트랜잭션 롤백 중 예외가 발생했습니다.");
+        }
+    }
+
+    private static void clear(final Connection connection) {
+        try {
+            connection.setAutoCommit(true);
+            connection.close();
+            DataSourceUtils.releaseConnection(connection);
+        } catch (final SQLException ex) {
+            throw new DataAccessException("커넥션 종료 중 예외가 발생했습니다.");
+        }
+    }
+}

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

@@ -0,0 +1,35 @@
+package com.techcourse.service;
+
+import com.techcourse.domain.User;
+
+public class TxUserService implements UserService {
+
+    private final AppUserService userService;
+    private final TransactionManager transactionManager;
+
+    public TxUserService(final AppUserService userService, final TransactionManager transactionManager) {
+        this.userService = userService;
+        this.transactionManager = transactionManager;
+    }
+
+    @Override
+    public User findById(final long id) {
+        return transactionManager.execute(() -> userService.findById(id));
+    }
+
+    @Override
+    public void insert(final User user) {
+        transactionManager.execute(() -> {
+            userService.insert(user);
+            return null;
+        });
+    }
+
+    @Override
+    public void changePassword(final long id, final String newPassword, final String createBy) {
+        transactionManager.execute(() -> {
+            userService.changePassword(id, newPassword, createBy);
+            return null;
+        });
+    }
+}

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

@@ -1,71 +1,14 @@
 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.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-import org.springframework.dao.DataAccessException;
-import org.springframework.jdbc.CannotGetJdbcConnectionException;
 
-import javax.sql.DataSource;
-import java.sql.Connection;
 import java.sql.SQLException;
 
-public class UserService {
+public interface UserService {
 
-    private static final Logger log = LoggerFactory.getLogger(UserService.class);
+    User findById(final long id) throws SQLException;
 
-    private final DataSource dataSource;
-    private final UserDao userDao;
-    private final UserHistoryDao userHistoryDao;
+    void insert(final User user) throws SQLException;
 
-    public UserService(final DataSource dataSource, final UserDao userDao, final UserHistoryDao userHistoryDao) {
-        this.dataSource = dataSource;
-        this.userDao = userDao;
-        this.userHistoryDao = userHistoryDao;
-    }
-
-    public User findById(final long id) {
-        return startTransaction(connection -> userDao.findById(connection, id));
-    }
-
-    public void insert(final User user) {
-        startTransaction(connection -> userDao.insert(connection, user));
-    }
-
-    public void changePassword(long id, final String newPassword, final String createBy) {
-        startTransaction(connection -> {
-            final var user = findById(id);
-            user.changePassword(newPassword);
-            userHistoryDao.log(connection, new UserHistory(user, createBy));
-            return userDao.update(connection, user);
-        });
-    }
-
-    public <T> T startTransaction(final TransactionExecutor<T> transactionExecutor) {
-        try (final Connection connection = dataSource.getConnection()) {
-            connection.setAutoCommit(false);
-
-            return commitTransaction(transactionExecutor, connection);
-        } catch (SQLException e) {
-            throw new CannotGetJdbcConnectionException("jdbc 연결에 실패했습니다.");
-        }
-    }
-
-    private <T> T commitTransaction(final TransactionExecutor<T> transactionExecutor, final Connection connection) throws SQLException {
-        try {
-            final T result = transactionExecutor.execute(connection);
-
-            connection.commit();
-
-            return result;
-        } catch (Exception ex) {
-            connection.rollback();
-
-            log.error(ex.getMessage());
-            throw new DataAccessException("실행 중 예외가 발생했습니다.");
-        }
-    }
+    void changePassword(final long id, final String newPassword, final String createBy) throws SQLException;
 }

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

@@ -25,27 +25,27 @@ void setup() throws SQLException {
 
         userDao = new UserDao(new JdbcTemplate(DataSourceConfig.getInstance()));
         final var user = new User("gugu", "password", "[email protected]");
-        userDao.insert(dataSource.getConnection(), user);
+        userDao.insert(user);
     }
 
     @Test
     void findAll() throws SQLException {
-        final var users = userDao.findAll(dataSource.getConnection());
+        final var users = userDao.findAll();
 
         assertThat(users).isNotEmpty();
     }
 
     @Test
     void findById() throws SQLException {
-        final var user = userDao.findById(dataSource.getConnection(), 1L);
+        final var user = userDao.findById(1L);
 
         assertThat(user.getAccount()).isEqualTo("gugu");
     }
 
     @Test
     void findByAccount() throws SQLException {
         final var account = "gugu";
-        final var user = userDao.findByAccount(dataSource.getConnection(), account);
+        final var user = userDao.findByAccount(account);
 
         assertThat(user.getAccount()).isEqualTo(account);
     }
@@ -55,9 +55,9 @@ void insert() throws SQLException {
         final var account = "insert-gugu";
         final var user = new User(account, "password", "[email protected]");
         final Connection connection = dataSource.getConnection();
-        userDao.insert(connection, user);
+        userDao.insert(user);
 
-        final var actual = userDao.findById(connection, 2L);
+        final var actual = userDao.findById(2L);
 
         assertThat(actual.getAccount()).isEqualTo(account);
     }
@@ -66,12 +66,12 @@ void insert() throws SQLException {
     void update() throws SQLException {
         final var newPassword = "password99";
         final Connection connection = dataSource.getConnection();
-        final var user = userDao.findById(connection, 1L);
+        final var user = userDao.findById(1L);
         user.changePassword(newPassword);
 
-        userDao.update(connection, user);
+        userDao.update(user);
 
-        final var actual = userDao.findById(connection, 1L);
+        final var actual = userDao.findById(1L);
 
         assertThat(actual.getPassword()).isEqualTo(newPassword);
     }