[JDBC 라이브러리 구현하기 - 4단계] 페드로(류형욱) 미션 제출합니다.

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

@@ -2,6 +2,7 @@
 
 import com.interface21.jdbc.core.JdbcTemplate;
 import com.interface21.jdbc.core.RowMapper;
+import com.interface21.jdbc.datasource.DataSourceUtils;
 import com.techcourse.domain.User;
 import java.sql.Connection;
 import java.util.List;
@@ -35,16 +36,11 @@ public void insert(User user) {
         jdbcTemplate.update(sql, user.getAccount(), user.getPassword(), user.getEmail());
     }
 
-    public void updateUsingExplicitConnection(User user, Connection connection) {
-        String sql = "UPDATE users SET account = ?, password = ?, email = ? where id = ?";
-        logSql(sql);
-        jdbcTemplate.update(connection, sql, user.getAccount(), user.getPassword(), user.getEmail(), user.getId());
-    }
-
-    public void update(final User user) {
+    public void update(User user) {
+        Connection connection = DataSourceUtils.getConnection(jdbcTemplate.getDataSource());
         String sql = "UPDATE users SET account = ?, password = ?, email = ? WHERE id = ?";
         logSql(sql);
-        jdbcTemplate.update(sql, user.getAccount(), user.getPassword(), user.getEmail(), user.getId());
+        jdbcTemplate.update(connection, sql, user.getAccount(), user.getPassword(), user.getEmail(), user.getId());
     }
 
     public List<User> findAll() {

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

@@ -2,6 +2,7 @@
 
 import com.interface21.jdbc.core.JdbcTemplate;
 import com.interface21.jdbc.core.RowMapper;
+import com.interface21.jdbc.datasource.DataSourceUtils;
 import com.techcourse.domain.UserHistory;
 import java.sql.Connection;
 import javax.sql.DataSource;
@@ -32,17 +33,7 @@ public UserHistoryDao(final DataSource dataSource) {
 
     public void log(UserHistory userHistory) {
         String sql = "INSERT INTO user_history (user_id, account, password, email, created_at, created_by) VALUES (?, ?, ?, ?, ?, ?)";
-        logSql(sql);
-
-        jdbcTemplate.update(
-                sql,
-                userHistory.getUserId(), userHistory.getAccount(), userHistory.getPassword(),
-                userHistory.getEmail(), userHistory.getCreatedAt(), userHistory.getCreateBy()
-        );
-    }
-
-    public void logUsingExplicitConnection(UserHistory userHistory, Connection connection) {
-        String sql = "INSERT INTO user_history (user_id, account, password, email, created_at, created_by) VALUES (?, ?, ?, ?, ?, ?)";
+        Connection connection = DataSourceUtils.getConnection(jdbcTemplate.getDataSource());
         logSql(sql);
         jdbcTemplate.update(
                 connection, sql,

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

@@ -0,0 +1,35 @@
+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 AppUserService implements UserService {
+
+    private final UserDao userDao;
+    private final UserHistoryDao userHistoryDao;
+
+    public AppUserService(UserDao userDao, UserHistoryDao userHistoryDao) {
+        this.userDao = userDao;
+        this.userHistoryDao = userHistoryDao;
+    }
+
+    @Override
+    public User findById(long id) {
+        return userDao.findById(id);
+    }
+
+    @Override
+    public void save(User user) {
+        userDao.insert(user);
+    }
+
+    @Override
+    public void changePassword(long id, String newPassword, String createBy) {
+        User user = findById(id);
+        user.changePassword(newPassword);
+        userDao.update(user);
+        userHistoryDao.log(new UserHistory(user, createBy));
+    }
+}

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

@@ -0,0 +1,33 @@
+package com.techcourse.service;
+
+import com.interface21.jdbc.transaction.TransactionManager;
+import com.techcourse.domain.User;
+import javax.sql.DataSource;
+
+public class TxUserService implements UserService {
+
+    private final AppUserService appUserService;
+    private final DataSource dataSource;
+
+    public TxUserService(AppUserService appUserService, DataSource dataSource) {
+        this.appUserService = appUserService;
+        this.dataSource = dataSource;
+    }
+
+    @Override
+    public User findById(long id) {
+        return appUserService.findById(id);
+    }
+
+    @Override
+    public void save(User user) {
+        appUserService.save(user);
+    }
+
+    @Override
+    public void changePassword(long id, String newPassword, String createBy) {
+        TransactionManager.executeTransactionOf(
+                connection -> appUserService.changePassword(id, newPassword, createBy), dataSource
+        );
+    }
+}

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

@@ -1,40 +1,12 @@
 package com.techcourse.service;
 
-import com.interface21.jdbc.transaction.TransactionManager;
-import com.techcourse.dao.UserDao;
-import com.techcourse.dao.UserHistoryDao;
 import com.techcourse.domain.User;
-import com.techcourse.domain.UserHistory;
-import java.sql.Connection;
 
-public class UserService {
+public interface UserService {
 
-    private final TransactionManager txManager;
-    private final UserDao userDao;
-    private final UserHistoryDao userHistoryDao;
+    User findById(long id);
 
-    public UserService(TransactionManager txManager, UserDao userDao, UserHistoryDao userHistoryDao) {
-        this.txManager = txManager;
-        this.userDao = userDao;
-        this.userHistoryDao = userHistoryDao;
-    }
+    void save(User user);
 
-    public User findById(long id) {
-        return userDao.findById(id);
-    }
-
-    public void insert(User user) {
-        userDao.insert(user);
-    }
-
-    public void changePassword(long id, String newPassword, String createBy) {
-        txManager.executeTransactionOf(conn -> changePasswordTx(conn, id, newPassword, createBy));
-    }
-
-    private void changePasswordTx(Connection connection, long id, String newPassword, String createBy) {
-        final var user = findById(id);
-        user.changePassword(newPassword);
-        userDao.updateUsingExplicitConnection(user, connection);
-        userHistoryDao.logUsingExplicitConnection(new UserHistory(user, createBy), connection);
-    }
+    void changePassword(long id, String newPassword, String createdBy);
 }

app/src/test/java/com/techcourse/service/MockUserHistoryDao.java

@@ -1,10 +1,9 @@
 package com.techcourse.service;
 
-import com.techcourse.dao.UserHistoryDao;
-import com.techcourse.domain.UserHistory;
 import com.interface21.dao.DataAccessException;
 import com.interface21.jdbc.core.JdbcTemplate;
-import java.sql.Connection;
+import com.techcourse.dao.UserHistoryDao;
+import com.techcourse.domain.UserHistory;
 
 public class MockUserHistoryDao extends UserHistoryDao {
 
@@ -13,7 +12,7 @@ public MockUserHistoryDao(final JdbcTemplate jdbcTemplate) {
     }
 
     @Override
-    public void logUsingExplicitConnection(UserHistory userHistory, Connection connection) {
+    public void log(UserHistory userHistory) {
         throw new DataAccessException();
     }
 }

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

@@ -1,11 +1,10 @@
 package com.techcourse.service;
 
 import static org.assertj.core.api.Assertions.assertThat;
-import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
 
 import com.interface21.dao.DataAccessException;
 import com.interface21.jdbc.core.JdbcTemplate;
-import com.interface21.jdbc.transaction.TransactionManager;
 import com.techcourse.config.DataSourceConfig;
 import com.techcourse.dao.UserDao;
 import com.techcourse.dao.UserHistoryDao;
@@ -17,14 +16,12 @@
 
 class UserServiceTest {
 
-    private TransactionManager txManager;
     private JdbcTemplate jdbcTemplate;
     private UserDao userDao;
 
     @BeforeEach
     void setUp() {
         DataSource dataSource = DataSourceConfig.getInstance();
-        txManager = new TransactionManager(dataSource);
         jdbcTemplate = new JdbcTemplate(dataSource);
         userDao = new UserDao(jdbcTemplate);
 
@@ -36,7 +33,7 @@ void setUp() {
     @Test
     void testChangePassword() {
         final var userHistoryDao = new UserHistoryDao(jdbcTemplate);
-        final var userService = new UserService(txManager, userDao, userHistoryDao);
+        final var userService = new AppUserService(userDao, userHistoryDao);
 
         final var newPassword = "qqqqq";
         final var createBy = "gugu";
@@ -51,13 +48,16 @@ void testChangePassword() {
     void testTransactionRollback() {
         // 트랜잭션 롤백 테스트를 위해 mock으로 교체
         final var userHistoryDao = new MockUserHistoryDao(jdbcTemplate);
-        final var userService = new UserService(txManager, userDao, userHistoryDao);
+        // 애플리케이션 서비스
+        final var appUserService = new AppUserService(userDao, userHistoryDao);
+        // 트랜잭션 서비스 추상화
+        final var userService = new TxUserService(appUserService, jdbcTemplate.getDataSource());
 
         final var newPassword = "newPassword";
-        final var createBy = "gugu";
+        final var createdBy = "gugu";
         // 트랜잭션이 정상 동작하는지 확인하기 위해 의도적으로 MockUserHistoryDao에서 예외를 발생시킨다.
-        assertThrows(DataAccessException.class,
-                () -> userService.changePassword(1L, newPassword, createBy));
+        assertThatThrownBy(() -> userService.changePassword(1L, newPassword, createdBy))
+                .isInstanceOf(DataAccessException.class);
 
         final var actual = userService.findById(1L);
 

jdbc/src/main/java/com/interface21/jdbc/core/JdbcTemplate.java

@@ -17,7 +17,7 @@ public class JdbcTemplate {
 
     private final DataSource dataSource;
 
-    public JdbcTemplate(final DataSource dataSource) {
+    public JdbcTemplate(DataSource dataSource) {
         this.dataSource = dataSource;
     }
 
@@ -37,7 +37,7 @@ public int update(Connection connection, String sql, Object... args) {
 
     public int update(String sql, PreparedStatementSetter psSetter) {
         try (Connection connection = dataSource.getConnection()) {
-             return update(new QueryConnectionHolder(connection, sql), psSetter);
+            return update(new QueryConnectionHolder(connection, sql), psSetter);
         } catch (SQLException e) {
             throw new DataAccessException("Update 실패", e);
         }
@@ -75,4 +75,8 @@ private <T> List<T> retrieveRow(RowMapper<T> rowMapper, PreparedStatement ps) th
         }
         return results;
     }
+
+    public DataSource getDataSource() {
+        return dataSource;
+    }
 }

jdbc/src/main/java/com/interface21/jdbc/datasource/DataSourceUtils.java

@@ -29,6 +29,8 @@ public static Connection getConnection(DataSource dataSource) throws CannotGetJd
 
     public static void releaseConnection(Connection connection, DataSource dataSource) {
         try {
+            Connection closingConnection = TransactionSynchronizationManager.unbindResource(dataSource);
+            assert closingConnection.equals(connection);
             connection.close();
         } catch (SQLException ex) {
             throw new CannotGetJdbcConnectionException("Failed to close JDBC Connection");

jdbc/src/main/java/com/interface21/jdbc/transaction/TransactionManager.java

@@ -1,6 +1,7 @@
 package com.interface21.jdbc.transaction;
 
 import com.interface21.dao.DataAccessException;
+import com.interface21.jdbc.datasource.DataSourceUtils;
 import java.sql.Connection;
 import java.sql.SQLException;
 import java.util.logging.Logger;
@@ -10,32 +11,29 @@ public class TransactionManager {
 
     private static final Logger log = Logger.getLogger(TransactionManager.class.getName());
 
-    private final DataSource dataSource;
-
-    public TransactionManager(DataSource dataSource) {
-        this.dataSource = dataSource;
+    private TransactionManager() {
     }
 
-    public void executeTransactionOf(TransactionalFunction callback) {
-        Connection connection = null;
+    public static void executeTransactionOf(TransactionalFunction callback, DataSource dataSource) {
+        Connection connection = DataSourceUtils.getConnection(dataSource);
         boolean shouldThrow = false;
         try {
-            connection = dataSource.getConnection();
             connection.setAutoCommit(false);
             callback.execute(connection);
             connection.commit();
         } catch (Exception e) {
             gracefulShutdown(connection, Connection::rollback);
             shouldThrow = true;
         } finally {
-            gracefulShutdown(connection, Connection::close);
+            DataSourceUtils.releaseConnection(connection, dataSource);
         }
+
         if (shouldThrow) {
             throw new DataAccessException("트랜잭션 실행 중 문제가 발생했습니다. 트랜잭션은 롤백됩니다.");
         }
     }
 
-    private void gracefulShutdown(Connection connection, ThrowingConsumer<Connection> connectionConsumer) {
+    private static void gracefulShutdown(Connection connection, ThrowingConsumer<Connection> connectionConsumer) {
         try {
             connectionConsumer.accept(connection);
         } catch (NullPointerException e) {

jdbc/src/main/java/com/interface21/transaction/support/TransactionSynchronizationManager.java

@@ -1,23 +1,36 @@
 package com.interface21.transaction.support;
 
+import java.util.HashMap;
 import javax.sql.DataSource;
 import java.sql.Connection;
 import java.util.Map;
 
 public abstract class TransactionSynchronizationManager {
 
-    private static final ThreadLocal<Map<DataSource, Connection>> resources = new ThreadLocal<>();
+    private static final ThreadLocal<Map<DataSource, Connection>> resources = ThreadLocal.withInitial(HashMap::new);
 
     private TransactionSynchronizationManager() {}
 
     public static Connection getResource(DataSource key) {
-        return null;
+        Map<DataSource, Connection> connections = resources.get();
+        return connections.get(key);
     }
 
     public static void bindResource(DataSource key, Connection value) {
+        Map<DataSource, Connection> connections = resources.get();
+        connections.put(key, value);
     }
 
     public static Connection unbindResource(DataSource key) {
-        return null;
+        Map<DataSource, Connection> connections = resources.get();
+        Connection unbindedConnection = connections.remove(key);
+        deAllocateIfEmpty(connections);
+        return unbindedConnection;
+    }
+
+    private static void deAllocateIfEmpty(Map<DataSource, Connection> connections) {
+        if (connections.isEmpty()) {
+            resources.remove();
+        }
     }
 }

jdbc/src/test/java/com/interface21/jdbc/transaction/TransactionManagerTest.java

@@ -30,13 +30,12 @@ void setUp() throws SQLException {
     @DisplayName("트랜잭션 실행 중 예외가 발생하면 롤백된다.")
     void rollbackOnException() throws SQLException {
         // given
-        TransactionManager txManager = new TransactionManager(dataSource);
         TransactionalFunction txFunction = conn -> {
             throw new SQLException();
         };
 
         // when & then
-        assertThatThrownBy(() -> txManager.executeTransactionOf(txFunction))
+        assertThatThrownBy(() -> TransactionManager.executeTransactionOf(txFunction, dataSource))
                 .isInstanceOf(DataAccessException.class);
         verify(connection).rollback();
         verify(connection, never()).commit();
@@ -46,9 +45,8 @@ void rollbackOnException() throws SQLException {
     @Test
     @DisplayName("예외 없는 트랜잭션은 정상적으로 커밋된다.")
     void commitOnNoException() throws SQLException {
-        TransactionManager txManager = new TransactionManager(dataSource);
         TransactionalFunction txFunction = conn -> {};
-        txManager.executeTransactionOf(txFunction);
+        TransactionManager.executeTransactionOf(txFunction, dataSource);
 
         verify(connection).commit();
         verify(connection, never()).rollback();