[4단계 - Transaction synchronization 적용하기] 미미(홍향미) 미션 제출합니다. (#1196)

* feat: DataSourceUtils 사용

* feat: UserService 추상화

* style: EOF 설정

Author: hongkikii

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;
+
+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) {
+        return userDao.findById(id)
+                .orElseThrow(() -> new IllegalArgumentException("User not found"));
+    }
+
+    @Override
+    public void save(final User user) {
+        userDao.insert(user);
+    }
+
+    @Override
+    public void changePassword(final long id, final String newPassword, final String createdBy) {
+        final var user = findById(id);
+        user.changePassword(newPassword);
+        userDao.update(user);
+
+        userHistoryDao.log(new UserHistory(user, createdBy));
+    }
+}

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

@@ -0,0 +1,39 @@
+package com.techcourse.service;
+
+import com.interface21.dao.DataAccessException;
+import com.interface21.transaction.DataSourceTransactionManager;
+import com.techcourse.config.DataSourceConfig;
+import com.techcourse.domain.User;
+
+public class TxUserService implements UserService {
+
+    private final UserService userService;
+    private final DataSourceTransactionManager transactionManager;
+
+    public TxUserService(final UserService userService) {
+        this.userService = userService;
+        this.transactionManager = new DataSourceTransactionManager(DataSourceConfig.getInstance());
+    }
+
+    @Override
+    public User findById(final long id) {
+        return userService.findById(id);
+    }
+
+    @Override
+    public void save(final User user) {
+        userService.save(user);
+    }
+
+    @Override
+    public void changePassword(final long id, final String newPassword, final String createdBy) {
+        transactionManager.bindConnection();
+        try {
+            userService.changePassword(id, newPassword, createdBy);
+            transactionManager.commit();
+        } catch (final Exception e) {
+            transactionManager.rollback();
+            throw new DataAccessException(e);
+        }
+    }
+}

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

@@ -1,50 +1,10 @@
 package com.techcourse.service;
 
-
-import com.interface21.dao.DataAccessException;
-import com.interface21.transaction.DataSourceTransactionManager;
-import com.techcourse.dao.UserDao;
-import com.techcourse.dao.UserHistoryDao;
 import com.techcourse.domain.User;
-import com.techcourse.domain.UserHistory;
-
-public class UserService {
-
-    private final UserDao userDao;
-    private final UserHistoryDao userHistoryDao;
-    private final DataSourceTransactionManager transactionManager;
-
-    public UserService(final UserDao userDao,
-                       final UserHistoryDao userHistoryDao,
-                       final DataSourceTransactionManager transactionManager
-    ) {
-        this.userDao = userDao;
-        this.userHistoryDao = userHistoryDao;
-        this.transactionManager = transactionManager;
-    }
-
-    public User findById(final long id) {
-        return userDao.findById(id)
-                .orElseThrow(() -> new IllegalArgumentException("User not found"));
-    }
-
-    public void insert(final User user) {
-        userDao.insert(user);
-    }
-
-    public void changePassword(final long id, final String newPassword, final String createBy) {
-        transactionManager.bindConnection();
-        try {
-            final var user = findById(id);
-            user.changePassword(newPassword);
-            userDao.update(user);
 
-            userHistoryDao.log(new UserHistory(user, createBy));
+public interface UserService {
 
-            transactionManager.commit();
-        } catch (final Exception e) {
-            transactionManager.rollback();
-            throw new DataAccessException(e);
-        }
-    }
+    User findById(final long id);
+    void save(final User user);
+    void changePassword(final long id, final String newPassword, final String createdBy);
 }

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

@@ -1,6 +1,5 @@
 package com.techcourse.service;
 
-import com.interface21.transaction.DataSourceTransactionManager;
 import com.techcourse.config.DataSourceConfig;
 import com.techcourse.dao.UserDao;
 import com.techcourse.dao.UserHistoryDao;
@@ -18,13 +17,11 @@ class UserServiceTest {
 
     private JdbcTemplate jdbcTemplate;
     private UserDao userDao;
-    private DataSourceTransactionManager transactionManager;
 
     @BeforeEach
     void setUp() {
         this.jdbcTemplate = new JdbcTemplate(DataSourceConfig.getInstance());
         this.userDao = new UserDao(jdbcTemplate);
-        this.transactionManager = new DataSourceTransactionManager(DataSourceConfig.getInstance());
 
         DatabasePopulatorUtils.execute(DataSourceConfig.getInstance());
         final var user = new User("gugu", "password", "[email protected]");
@@ -34,7 +31,8 @@ void setUp() {
     @Test
     void testChangePassword() {
         final var userHistoryDao = new UserHistoryDao(jdbcTemplate);
-        final var userService = new UserService(userDao, userHistoryDao, transactionManager);
+        final var appUserService = new AppUserService(userDao, userHistoryDao);
+        final var userService = new TxUserService(appUserService);
 
         final var newPassword = "qqqqq";
         final var createBy = "gugu";
@@ -49,13 +47,16 @@ void testChangePassword() {
     void testTransactionRollback() {
         // 트랜잭션 롤백 테스트를 위해 mock으로 교체
         final var userHistoryDao = new MockUserHistoryDao(jdbcTemplate);
-        final var userService = new UserService(userDao, userHistoryDao, transactionManager);
+        // 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";
+        final var createdBy = "gugu";
         // 트랜잭션이 정상 동작하는지 확인하기 위해 의도적으로 MockUserHistoryDao에서 예외를 발생시킨다.
         assertThrows(DataAccessException.class,
-                () -> userService.changePassword(1L, newPassword, createBy));
+                () -> userService.changePassword(1L, newPassword, createdBy));
 
         final var actual = userService.findById(1L);
 

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

@@ -2,36 +2,42 @@
 
 import com.interface21.jdbc.CannotGetJdbcConnectionException;
 import com.interface21.transaction.support.TransactionSynchronizationManager;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import javax.sql.DataSource;
 import java.sql.Connection;
 import java.sql.SQLException;
 
-// 4단계 미션에서 사용할 것
 public abstract class DataSourceUtils {
 
-    private DataSourceUtils() {}
+    private static final Logger log = LoggerFactory.getLogger(DataSourceUtils.class);
 
-    public static Connection getConnection(DataSource dataSource) throws CannotGetJdbcConnectionException {
-        Connection connection = TransactionSynchronizationManager.getResource(dataSource);
+    private DataSourceUtils() {
+    }
+
+    public static Connection getConnection(final DataSource dataSource) {
+        final var connection = TransactionSynchronizationManager.getResource(dataSource);
         if (connection != null) {
             return connection;
         }
-
         try {
-            connection = dataSource.getConnection();
-            TransactionSynchronizationManager.bindResource(dataSource, connection);
-            return connection;
-        } catch (SQLException ex) {
-            throw new CannotGetJdbcConnectionException("Failed to obtain JDBC Connection", ex);
+            return dataSource.getConnection();
+        } catch (final SQLException e) {
+            throw new CannotGetJdbcConnectionException("Failed to obtain JDBC Connection", e);
         }
     }
 
-    public static void releaseConnection(Connection connection, DataSource dataSource) {
-        try {
-            connection.close();
-        } catch (SQLException ex) {
-            throw new CannotGetJdbcConnectionException("Failed to close JDBC Connection");
+    public static void releaseConnection(final Connection connection, final DataSource dataSource) {
+        if (TransactionSynchronizationManager.hasResource(dataSource)) {
+            return;
+        }
+        if (connection != null) {
+            try {
+                connection.close();
+            } catch (final SQLException e) {
+                log.debug("Could not close JDBC Connection", e);
+            }
         }
     }
 }