[JDBC 라이브러리 구현 4단계] 메리(최승원) 미션 제출합니다

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

@@ -6,6 +6,7 @@
 import org.springframework.jdbc.core.JdbcTemplate;
 import org.springframework.jdbc.core.RowMapper;
 
+import java.sql.SQLException;
 import java.util.List;
 
 public class UserDao {
@@ -25,29 +26,29 @@ public UserDao(final JdbcTemplate jdbcTemplate) {
         this.jdbcTemplate = jdbcTemplate;
     }
 
-    public int insert(final User user) {
+    public int insert(final User user) throws SQLException {
         final var sql = "insert into users (account, password, email) values (?, ?, ?)";
         log.debug("query : {}", sql);
 
         return updateQuery(sql, user.getAccount(), user.getPassword(), user.getEmail());
     }
 
-    private int updateQuery(final String sql, final Object... 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 User user) {
+    public int update(final User user) throws SQLException {
         final var sql = "update users set (account, password, email) = (?, ?, ?)";
         log.debug("query : {}", sql);
 
         return updateQuery(sql, user.getAccount(), user.getPassword(), user.getEmail());
     }
 
-    public List<User> findAll() {
+    public List<User> findAll() throws SQLException {
         final var sql = "select id, account, password, email from users";
         final List<User> users = jdbcTemplate.query(sql, userRowMapper);
 
@@ -56,7 +57,7 @@ public List<User> findAll() {
         return users;
     }
 
-    public User findById(final Long id) {
+    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(sql, userRowMapper, id)
                                       .orElseThrow(() -> new RuntimeException("찾는 사용자가 존재하지 않습니다."));
@@ -66,7 +67,7 @@ public User findById(final Long id) {
         return user;
     }
 
-    public User findByAccount(final String account) {
+    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(sql, userRowMapper, account)
                                       .orElseThrow(() -> new RuntimeException("찾는 사용자가 존재하지 않습니다."));

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

@@ -5,6 +5,8 @@
 import org.slf4j.LoggerFactory;
 import org.springframework.jdbc.core.JdbcTemplate;
 
+import java.sql.SQLException;
+
 public class UserHistoryDao {
 
     private static final Logger log = LoggerFactory.getLogger(UserHistoryDao.class);
@@ -15,7 +17,7 @@ public UserHistoryDao(final JdbcTemplate jdbcTemplate) {
         this.jdbcTemplate = jdbcTemplate;
     }
 
-    public void log(final UserHistory userHistory) {
+    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(
                 sql,

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

@@ -5,6 +5,8 @@
 import com.techcourse.domain.User;
 import com.techcourse.domain.UserHistory;
 
+import java.sql.SQLException;
+
 public class AppUserService implements UserService {
 
     private final UserDao userDao;
@@ -16,20 +18,20 @@ public AppUserService(final UserDao userDao, final UserHistoryDao userHistoryDao
     }
 
     @Override
-    public User findById(final long id) {
+    public User findById(final long id) throws SQLException {
         return userDao.findById(id);
     }
 
     @Override
-    public void insert(final User user) {
+    public void insert(final User user) throws SQLException {
         userDao.insert(user);
     }
 
     @Override
-    public void changePassword(long id, final String newPassword, final String createBy) {
+    public void changePassword(long id, final String newPassword, final String createBy) throws SQLException {
         final var user = findById(id);
         user.changePassword(newPassword);
-        userHistoryDao.log(new UserHistory(user, createBy));
         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

@@ -1,42 +1,35 @@
 package com.techcourse.service;
 
 import com.techcourse.domain.User;
-import org.springframework.transaction.support.TransactionSynchronizationManager;
 
 public class TxUserService implements UserService {
 
     private final AppUserService userService;
+    private final TransactionManager transactionManager;
 
-    public TxUserService(final AppUserService userService) {
+    public TxUserService(final AppUserService userService, final TransactionManager transactionManager) {
         this.userService = userService;
+        this.transactionManager = transactionManager;
     }
 
     @Override
     public User findById(final long id) {
-        TransactionSynchronizationManager.startTransaction();
-
-        final User findUser = userService.findById(id);
-
-        TransactionSynchronizationManager.finishTransaction();
-
-        return findUser;
+        return transactionManager.execute(() -> userService.findById(id));
     }
 
     @Override
     public void insert(final User user) {
-        TransactionSynchronizationManager.startTransaction();
-
-        userService.insert(user);
-
-        TransactionSynchronizationManager.finishTransaction();
+        transactionManager.execute(() -> {
+            userService.insert(user);
+            return null;
+        });
     }
 
     @Override
     public void changePassword(final long id, final String newPassword, final String createBy) {
-        TransactionSynchronizationManager.startTransaction();
-
-        userService.changePassword(id, newPassword, createBy);
-
-        TransactionSynchronizationManager.finishTransaction();
+        transactionManager.execute(() -> {
+            userService.changePassword(id, newPassword, createBy);
+            return null;
+        });
     }
 }

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

@@ -2,11 +2,13 @@
 
 import com.techcourse.domain.User;
 
+import java.sql.SQLException;
+
 public interface UserService {
 
-    User findById(final long id);
+    User findById(final long id) throws SQLException;
 
-    void insert(final User user);
+    void insert(final User user) throws SQLException;
 
-    void changePassword(final long id, final String newPassword, final String createBy);
+    void changePassword(final long id, final String newPassword, final String createBy) throws SQLException;
 }

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

@@ -10,6 +10,7 @@
 import org.springframework.dao.DataAccessException;
 import org.springframework.jdbc.core.JdbcTemplate;
 
+import javax.sql.DataSource;
 import java.sql.SQLException;
 
 import static org.assertj.core.api.Assertions.assertThat;
@@ -25,13 +26,14 @@ void setUp() throws SQLException {
         this.jdbcTemplate = new JdbcTemplate(DataSourceConfig.getInstance());
         this.userDao = new UserDao(jdbcTemplate);
 
-        DatabasePopulatorUtils.execute(DataSourceConfig.getInstance());
+        final DataSource dataSource = DataSourceConfig.getInstance();
+        DatabasePopulatorUtils.execute(dataSource);
         final var user = new User("gugu", "password", "[email protected]");
         userDao.insert(user);
     }
 
     @Test
-    void testChangePassword() {
+    void testChangePassword() throws SQLException {
         final var userHistoryDao = new UserHistoryDao(jdbcTemplate);
         final var userService = new AppUserService(userDao, userHistoryDao);
 
@@ -51,7 +53,8 @@ void testTransactionRollback() {
         // 애플리케이션 서비스
         final var appUserService = new AppUserService(userDao, userHistoryDao);
         // 트랜잭션 서비스 추상화
-        final var userService = new TxUserService(appUserService);
+        final var transactionManager = new TransactionManager(DataSourceConfig.getInstance());
+        final var userService = new TxUserService(appUserService, transactionManager);
 
         final var newPassword = "newPassword";
         final var createBy = "gugu";

jdbc/src/main/java/org/springframework/jdbc/core/JdbcTemplate.java

@@ -2,7 +2,7 @@
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
-import org.springframework.jdbc.CannotGetJdbcConnectionException;
+import org.springframework.dao.DataAccessException;
 import org.springframework.transaction.support.TransactionSynchronizationManager;
 
 import javax.sql.DataSource;
@@ -25,20 +25,20 @@ public JdbcTemplate(final DataSource dataSource) {
         this.dataSource = dataSource;
     }
 
-    public <T> Optional<T> queryForObject(final String sql, final RowMapper<T> rowMapper, final Object... parameters) {
+    public <T> Optional<T> queryForObject(final String sql, final RowMapper<T> rowMapper, final Object... parameters) throws SQLException {
         return execute(sql, preparedStatement -> {
             final ResultSet resultSet = preparedStatement.executeQuery();
             if (resultSet.next()) {
                 return Optional.of(rowMapper.mapRow(resultSet));
             }
             if (!resultSet.isLast()) {
-                throw new RuntimeException("단일 데이터가 아닙니다.");
+                throw new DataAccessException("단일 데이터가 아닙니다.");
             }
             return Optional.empty();
         }, parameters);
     }
 
-    public <T> List<T> query(final String sql, final RowMapper<T> rowMapper) {
+    public <T> List<T> query(final String sql, final RowMapper<T> rowMapper) throws SQLException {
         return execute(sql, preparedStatement -> {
             final ResultSet resultSet = preparedStatement.executeQuery();
             final List<T> objects = new ArrayList<>();
@@ -50,24 +50,24 @@ public <T> List<T> query(final String sql, final RowMapper<T> rowMapper) {
         });
     }
 
-    public int update(final String sql, final Object... parameters) {
+    public int update(final String sql, final Object... parameters) throws SQLException {
         return execute(sql, PreparedStatement::executeUpdate, parameters);
     }
 
-    public <T> T execute(final String sql, final ExecuteQueryCallback<T> callBack, final Object... objects) {
-        try {
-            final Connection connection = TransactionSynchronizationManager.getResource(dataSource);
-            final PreparedStatement preparedStatement = connection.prepareStatement(sql);
+    public <T> T execute(
+            final String sql,
+            final ExecuteQueryCallback<T> callBack,
+            final Object... objects
+    ) throws SQLException {
+        final PreparedStatement preparedStatement = createPreparedStatement(sql);
+        setPreparedStatement(preparedStatement, objects);
 
-            setPreparedStatement(preparedStatement, objects);
-
-            return TransactionSynchronizationManager.commit(callBack, preparedStatement, dataSource);
-        } catch (SQLException ex) {
-            TransactionSynchronizationManager.rollback(dataSource);
+        return callBack.execute(preparedStatement);
+    }
 
-            log.error(ex.getMessage());
-            throw new CannotGetJdbcConnectionException("jdbc 연결에 실패했습니다.");
-        }
+    private PreparedStatement createPreparedStatement(final String sql) throws SQLException {
+        final Connection connection = TransactionSynchronizationManager.getResource(dataSource);
+        return connection.prepareStatement(sql);
     }
 
     private void setPreparedStatement(final PreparedStatement preparedStatement, final Object[] parameters) throws SQLException {

jdbc/src/main/java/org/springframework/jdbc/datasource/DataSourceUtils.java

@@ -1,7 +1,6 @@
 package org.springframework.jdbc.datasource;
 
 import org.springframework.jdbc.CannotGetJdbcConnectionException;
-import org.springframework.transaction.support.TransactionSynchronizationManager;
 
 import javax.sql.DataSource;
 import java.sql.Connection;
@@ -12,18 +11,17 @@ public abstract class DataSourceUtils {
     private DataSourceUtils() {
     }
 
-    public static Connection getConnection(DataSource dataSource) throws CannotGetJdbcConnectionException, SQLException {
+    public static Connection getConnection(final DataSource dataSource) throws CannotGetJdbcConnectionException, SQLException {
         try {
-            return TransactionSynchronizationManager.getResource(dataSource);
+            return dataSource.getConnection();
         } catch (SQLException ex) {
             throw new CannotGetJdbcConnectionException("Failed to obtain JDBC Connection", ex);
         }
     }
 
-    public static void releaseConnection(Connection connection, DataSource dataSource) {
+    public static void releaseConnection(final Connection connection) {
         try {
             connection.close();
-            TransactionSynchronizationManager.unbindResource(dataSource);
         } catch (SQLException ex) {
             throw new CannotGetJdbcConnectionException("Failed to close JDBC Connection");
         }