[JDBC 라이브러리 구현하기 - 4단계] 에단(김석호) 미션 제출합니다.

README.md

@@ -8,3 +8,5 @@
   - [x] update()
 - [x] JdbcTemplate 으로 중복 제거
 - [x] 트랜잭션 경계 설정하기
+- [x] Transaction synchronization 적용하기
+- [x] 트랜잭션 서비스 추상화하기

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

@@ -4,7 +4,6 @@
 import org.springframework.jdbc.core.JdbcTemplate;
 import org.springframework.jdbc.core.RowMapper;
 
-import java.sql.Connection;
 import java.util.List;
 import java.util.Optional;
 
@@ -33,12 +32,6 @@ public void update(final User user) {
         jdbcTemplate.execute(sql, user.getAccount(), user.getPassword(), user.getEmail(), user.getId());
     }
 
-    public void update(final Connection connection, final User user) {
-        final var sql = "update users set (account, password, email) = (?, ?, ?) where id = ?";
-
-        jdbcTemplate.executeWithConnection(connection, sql, user.getAccount(), user.getPassword(), user.getEmail(), user.getId());
-    }
-
     List<User> findAll() {
         final var sql = "select id, account, password, email from users";
 

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

@@ -3,8 +3,6 @@
 import com.techcourse.domain.UserHistory;
 import org.springframework.jdbc.core.JdbcTemplate;
 
-import java.sql.Connection;
-
 public class UserHistoryDao {
 
     private final JdbcTemplate jdbcTemplate;
@@ -25,18 +23,4 @@ public void log(final UserHistory userHistory) {
                 userHistory.getCreateBy()
         );
     }
-
-    public void log(final Connection connection, final UserHistory userHistory) {
-        final var sql = "insert into user_history (user_id, account, password, email, created_at, created_by) values (?, ?, ?, ?, ?, ?)";
-
-        jdbcTemplate.executeWithConnection(connection,
-                sql,
-                userHistory.getUserId(),
-                userHistory.getAccount(),
-                userHistory.getPassword(),
-                userHistory.getEmail(),
-                userHistory.getCreatedAt(),
-                userHistory.getCreateBy()
-        );
-    }
 }

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(String.format("id 값으로 해당하는 User 를 찾을 수 없습니다. 입력값 : %s", id)));
+    }
+
+    @Override
+    public void insert(final User user) {
+        userDao.insert(user);
+    }
+
+    @Override
+    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));
+    }
+}

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

@@ -0,0 +1,30 @@
+package com.techcourse.service;
+
+import com.techcourse.domain.User;
+import org.springframework.transaction.support.TransactionTemplate;
+
+public class TxUserService implements UserService {
+
+    private final UserService userService;
+    private final TransactionTemplate transactionTemplate;
+
+    public TxUserService(final UserService userService, final TransactionTemplate transactionTemplate) {
+        this.userService = userService;
+        this.transactionTemplate = transactionTemplate;
+    }
+
+    @Override
+    public User findById(final long id) {
+        return transactionTemplate.queryWithTransaction(() -> userService.findById(id));
+    }
+
+    @Override
+    public void insert(final User user) {
+        transactionTemplate.executeWithTransaction(() -> userService.insert(user));
+    }
+
+    @Override
+    public void changePassword(final long id, final String newPassword, final String createBy) {
+        transactionTemplate.executeWithTransaction(() -> userService.changePassword(id, newPassword, createBy));
+    }
+}

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

@@ -1,83 +1,12 @@
 package com.techcourse.service;
 
-import com.techcourse.config.DataSourceConfig;
-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 javax.sql.DataSource;
-import java.sql.Connection;
-import java.sql.SQLException;
-import java.util.NoSuchElementException;
+public interface UserService {
 
-public class UserService {
+    User findById(final long id);
 
-    private static final Logger log = LoggerFactory.getLogger(UserService.class);
+    void insert(final User user);
 
-    private final UserDao userDao;
-    private final UserHistoryDao userHistoryDao;
-
-    UserService(final UserDao userDao, final UserHistoryDao userHistoryDao) {
-        this.userDao = userDao;
-        this.userHistoryDao = userHistoryDao;
-    }
-
-    User findById(final long id) {
-        return userDao.findById(id)
-                .orElseThrow(() -> new NoSuchElementException("id 값으로 해당하는 User 를 찾을 수 없습니다."));
-    }
-
-    public void insert(final User user) {
-        userDao.insert(user);
-    }
-
-    void changePassword(final long id, final String newPassword, final String createBy) {
-        final var user = findById(id);
-        user.changePassword(newPassword);
-
-        Connection connection = null;
-        try {
-            final DataSource dataSource = DataSourceConfig.getInstance();
-            connection = dataSource.getConnection();
-            connection.setAutoCommit(false);
-
-            userDao.update(connection, user);
-            userHistoryDao.log(connection, new UserHistory(user, createBy));
-
-            connection.commit();
-        } catch (final SQLException | DataAccessException e) {
-            rollback(connection);
-            log.error("SQLException occurred");
-            throw new DataAccessException(e);
-        } finally {
-            release(connection);
-        }
-    }
-
-    private void rollback(final Connection connection) {
-        if (connection != null) {
-            try {
-                connection.rollback();
-            } catch (final SQLException ex) {
-                log.error("rollback callback");
-                throw new DataAccessException(ex);
-            }
-        }
-    }
-
-    private void release(final Connection connection) {
-        if (connection != null) {
-            try {
-                connection.setAutoCommit(true);
-                connection.close();
-            } catch (final SQLException e) {
-                log.error("Cannot close Connection");
-                throw new DataAccessException(e);
-            }
-        }
-    }
+    void changePassword(final long id, final String newPassword, final String createBy);
 }

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

@@ -5,16 +5,14 @@
 import org.springframework.dao.DataAccessException;
 import org.springframework.jdbc.core.JdbcTemplate;
 
-import java.sql.Connection;
-
 public class MockUserHistoryDao extends UserHistoryDao {
 
     MockUserHistoryDao(final JdbcTemplate jdbcTemplate) {
         super(jdbcTemplate);
     }
 
     @Override
-    public void log(final Connection connection, final UserHistory userHistory) {
+    public void log(final UserHistory userHistory) {
         throw new DataAccessException();
     }
 }

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

@@ -9,6 +9,7 @@
 import org.junit.jupiter.api.Test;
 import org.springframework.dao.DataAccessException;
 import org.springframework.jdbc.core.JdbcTemplate;
+import org.springframework.transaction.support.TransactionTemplate;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.junit.jupiter.api.Assertions.assertThrows;
@@ -33,7 +34,7 @@ void setUp() {
 
     @Test
     void testChangePassword() {
-        final var userService = new UserService(userDao, userHistoryDao);
+        final var userService = new AppUserService(userDao, userHistoryDao);
 
         final var newPassword = "qqqqq";
         final var createBy = "gugu";
@@ -47,7 +48,10 @@ void testChangePassword() {
     @Test
     void testTransactionRollback() {
         // 트랜잭션 롤백 테스트를 위해 mock으로 교체
-        final var userService = new UserService(userDao, mockUserHistoryDao);
+        // 애플리케이션 서비스
+        final var appUserService = new AppUserService(userDao, mockUserHistoryDao);
+        // 트랜잭션 서비스 추상화
+        final var userService = new TxUserService(appUserService, new TransactionTemplate(DataSourceConfig.getInstance()));
 
         final var newPassword = "newPassword";
         final var createBy = "gugu";

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

@@ -3,6 +3,7 @@
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.dao.DataAccessException;
+import org.springframework.jdbc.datasource.DataSourceUtils;
 
 import javax.sql.DataSource;
 import java.sql.Connection;
@@ -24,8 +25,8 @@ public JdbcTemplate(final DataSource dataSource) {
     }
 
     public void execute(final String sql, final Object... params) {
+        final Connection conn = DataSourceUtils.getConnection(dataSource);
         try (
-                final Connection conn = dataSource.getConnection();
                 final PreparedStatement pstmt = conn.prepareStatement(sql)
         ) {
             log.debug("query : {}", sql);
@@ -34,27 +35,13 @@ public void execute(final String sql, final Object... params) {
 
             pstmt.executeUpdate();
         } catch (final SQLException e) {
-            log.error(e.getMessage(), e);
-            throw new DataAccessException(e);
-        }
-    }
-
-    public void executeWithConnection(final Connection conn, final String sql, final Object... params) {
-        try (final PreparedStatement pstmt = conn.prepareStatement(sql)) {
-            log.debug("query : {}", sql);
-
-            setCondition(params, pstmt);
-
-            pstmt.executeUpdate();
-        } catch (final SQLException e) {
-            log.error(e.getMessage(), e);
             throw new DataAccessException(e);
         }
     }
 
     public <T> List<T> query(final String sql, final RowMapper<T> rowMapper) {
+        final Connection conn = DataSourceUtils.getConnection(dataSource);
         try (
-                final Connection conn = dataSource.getConnection();
                 final PreparedStatement pstmt = conn.prepareStatement(sql);
                 final ResultSet rs = pstmt.executeQuery()
         ) {
@@ -69,14 +56,13 @@ public <T> List<T> query(final String sql, final RowMapper<T> rowMapper) {
 
             return results;
         } catch (final SQLException e) {
-            log.error(e.getMessage(), e);
             throw new DataAccessException(e);
         }
     }
 
     public <T> Optional<T> queryForObject(final String sql, final RowMapper<T> rowMapper, final Object... params) {
+        final Connection conn = DataSourceUtils.getConnection(dataSource);
         try (
-                final Connection conn = dataSource.getConnection();
                 final PreparedStatement pstmt = getPreparedStatement(conn, sql, params);
                 final ResultSet rs = pstmt.executeQuery()
         ) {
@@ -89,7 +75,6 @@ public <T> Optional<T> queryForObject(final String sql, final RowMapper<T> rowMa
 
             return Optional.empty();
         } catch (final SQLException e) {
-            log.error(e.getMessage(), e);
             throw new DataAccessException(e);
         }
     }

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

@@ -12,7 +12,7 @@ public abstract class DataSourceUtils {
 
     private DataSourceUtils() {}
 
-    public static Connection getConnection(DataSource dataSource) throws CannotGetJdbcConnectionException {
+    public static Connection getConnection(final DataSource dataSource) throws CannotGetJdbcConnectionException {
         Connection connection = TransactionSynchronizationManager.getResource(dataSource);
         if (connection != null) {
             return connection;
@@ -22,15 +22,15 @@ public static Connection getConnection(DataSource dataSource) throws CannotGetJd
             connection = dataSource.getConnection();
             TransactionSynchronizationManager.bindResource(dataSource, connection);
             return connection;
-        } catch (SQLException ex) {
+        } catch (final 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, final DataSource dataSource) {
         try {
             connection.close();
-        } catch (SQLException ex) {
+        } catch (final SQLException ex) {
             throw new CannotGetJdbcConnectionException("Failed to close JDBC Connection");
         }
     }

jdbc/src/main/java/org/springframework/transaction/TransactionException.java

@@ -0,0 +1,8 @@
+package org.springframework.transaction;
+
+public class TransactionException extends RuntimeException {
+
+    public TransactionException(final String message) {
+        super(message);
+    }
+}

jdbc/src/main/java/org/springframework/transaction/support/TransactionCommandExecutor.java

@@ -0,0 +1,7 @@
+package org.springframework.transaction.support;
+
+@FunctionalInterface
+public interface TransactionCommandExecutor {
+
+    void run();
+}

jdbc/src/main/java/org/springframework/transaction/support/TransactionQueryExecutor.java

@@ -0,0 +1,7 @@
+package org.springframework.transaction.support;
+
+@FunctionalInterface
+public interface TransactionQueryExecutor<T> {
+
+    T get();
+}