[3단계 - Transaction 적용하기] 벨로(방예혁) 미션 제출합니다.

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

@@ -2,6 +2,7 @@
 
 import com.interface21.jdbc.core.JdbcTemplate;
 import com.techcourse.domain.User;
+import java.sql.Connection;
 import java.util.List;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -17,27 +18,43 @@ public UserDao(final JdbcTemplate jdbcTemplate) {
     }
 
     public void insert(final User user) {
-        final var sql = """
+        final String sql = """
                 INSERT INTO users (account, password, email)
                 VALUES (?, ?, ?)
                 """;
+        log.debug("Inserting user: {}", user);
         jdbcTemplate.insert(sql, user.getAccount(), user.getPassword(), user.getEmail());
     }
 
     public void update(final User user) {
-        final var sql = """
+        final String sql = """
                 UPDATE users
                 SET password = ?
                 WHERE id = ?
                 """;
+        log.debug("Updating user: {}", user);
         jdbcTemplate.update(sql, user.getPassword(), user.getId());
     }
 
+    public void update(
+            final Connection connection,
+            final User user
+    ) {
+        final String sql = """
+                UPDATE users
+                SET password = ?
+                WHERE id = ?
+                """;
+        log.debug("Updating user: {}", user);
+        jdbcTemplate.update(connection, sql, user.getPassword(), user.getId());
+    }
+
     public List<User> findAll() {
-        final var sql = """
+        final String sql = """
                 SELECT id, account, password, email
                 FROM users
                 """;
+        log.debug("Finding all users");
         return jdbcTemplate.findAll(sql, (rs) -> new User(
                 rs.getLong(1),
                 rs.getString(2),
@@ -47,11 +64,12 @@ public List<User> findAll() {
     }
 
     public User findById(final Long id) {
-        final var sql = """
+        final String sql = """
                 SELECT id, account, password, email
                 FROM users
                 WHERE id = ?
                 """;
+        log.debug("Finding user by id: {}", id);
         return jdbcTemplate.queryForObject(sql, (rs) -> new User(
                 rs.getLong(1),
                 rs.getString(2),
@@ -61,11 +79,12 @@ public User findById(final Long id) {
     }
 
     public User findByAccount(final String account) {
-        final var sql = """
+        final String sql = """
                 SELECT id, account, password, email
                 FROM users
                 WHERE account = ?
                 """;
+        log.debug("Finding user by account: {}", account);
         return jdbcTemplate.queryForObject(sql, (rs) -> new User(
                 rs.getLong("id"),
                 rs.getString("account"),

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

@@ -1,62 +1,53 @@
 package com.techcourse.dao;
 
-import com.techcourse.domain.UserHistory;
 import com.interface21.jdbc.core.JdbcTemplate;
+import com.techcourse.domain.UserHistory;
+import java.sql.Connection;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import javax.sql.DataSource;
-import java.sql.Connection;
-import java.sql.PreparedStatement;
-import java.sql.SQLException;
-
 public class UserHistoryDao {
 
     private static final Logger log = LoggerFactory.getLogger(UserHistoryDao.class);
 
-    private final DataSource dataSource;
-
-    public UserHistoryDao(final DataSource dataSource) {
-        this.dataSource = dataSource;
-    }
+    private final JdbcTemplate jdbcTemplate;
 
     public UserHistoryDao(final JdbcTemplate jdbcTemplate) {
-        this.dataSource = null;
+        this.jdbcTemplate = jdbcTemplate;
     }
 
     public void log(final UserHistory userHistory) {
-        final var sql = "insert into user_history (user_id, account, password, email, created_at, created_by) values (?, ?, ?, ?, ?, ?)";
-
-        Connection conn = null;
-        PreparedStatement pstmt = null;
-        try {
-            conn = dataSource.getConnection();
-            pstmt = conn.prepareStatement(sql);
-
-            log.debug("query : {}", sql);
-
-            pstmt.setLong(1, userHistory.getUserId());
-            pstmt.setString(2, userHistory.getAccount());
-            pstmt.setString(3, userHistory.getPassword());
-            pstmt.setString(4, userHistory.getEmail());
-            pstmt.setObject(5, userHistory.getCreatedAt());
-            pstmt.setString(6, userHistory.getCreateBy());
-            pstmt.executeUpdate();
-        } catch (SQLException e) {
-            log.error(e.getMessage(), e);
-            throw new RuntimeException(e);
-        } finally {
-            try {
-                if (pstmt != null) {
-                    pstmt.close();
-                }
-            } catch (SQLException ignored) {}
+        final var sql = """
+                INSERT INTO user_history (user_id, account, password, email, created_at, created_by)
+                VALUES (?, ?, ?, ?, ?, ?)
+                """;
+        log.debug("User history log: {}", userHistory);
+        jdbcTemplate.update(sql,
+                userHistory.getUserId(),
+                userHistory.getAccount(),
+                userHistory.getPassword(),
+                userHistory.getEmail(),
+                userHistory.getCreatedAt(),
+                userHistory.getCreateBy()
+        );
+    }
 
-            try {
-                if (conn != null) {
-                    conn.close();
-                }
-            } catch (SQLException ignored) {}
-        }
+    public void log(
+            final Connection connection,
+            final UserHistory userHistory
+    ) {
+        final String sql = """
+                INSERT INTO user_history (user_id, account, password, email, created_at, created_by)
+                VALUES (?, ?, ?, ?, ?, ?)
+                """;
+        log.debug("User history log: {}", userHistory);
+        jdbcTemplate.update(connection, sql,
+                userHistory.getUserId(),
+                userHistory.getAccount(),
+                userHistory.getPassword(),
+                userHistory.getEmail(),
+                userHistory.getCreatedAt(),
+                userHistory.getCreateBy()
+        );
     }
 }

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

@@ -1,18 +1,28 @@
 package com.techcourse.service;
 
+import com.interface21.dao.DataAccessException;
 import com.techcourse.dao.UserDao;
 import com.techcourse.dao.UserHistoryDao;
 import com.techcourse.domain.User;
 import com.techcourse.domain.UserHistory;
+import java.sql.Connection;
+import java.sql.SQLException;
+import javax.sql.DataSource;
 
-public class UserService {
+public final class UserService {
 
     private final UserDao userDao;
     private final UserHistoryDao userHistoryDao;
+    private final DataSource dataSource;
 
-    public UserService(final UserDao userDao, final UserHistoryDao userHistoryDao) {
+    public UserService(
+            final UserDao userDao,
+            final UserHistoryDao userHistoryDao,
+            final DataSource dataSource
+    ) {
         this.userDao = userDao;
         this.userHistoryDao = userHistoryDao;
+        this.dataSource = dataSource;
     }
 
     public User findById(final long id) {
@@ -23,10 +33,25 @@ public void insert(final User user) {
         userDao.insert(user);
     }
 
-    public void changePassword(final long id, final String newPassword, final String createBy) {
-        final var user = findById(id);
+    public void changePassword(
+            final long id,
+            final String newPassword,
+            final String createBy
+    ) {
+        final User user = findById(id);
         user.changePassword(newPassword);
-        userDao.update(user);
-        userHistoryDao.log(new UserHistory(user, createBy));
+        try (final Connection connection = dataSource.getConnection()) {
+            connection.setAutoCommit(false);
+            try {
+                userDao.update(connection, user);
+                userHistoryDao.log(connection, new UserHistory(user, createBy));
+                connection.commit();
+            } catch (final Exception e) {
+                connection.rollback();
+                throw new DataAccessException("비밀번호 변경 중 오류가 발생했습니다.", e);
+            }
+        } catch (final SQLException e) {
+            throw new DataAccessException("데이터베이스 연결 중 오류가 발생했습니다.", e);
+        }
     }
 }

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

@@ -1,9 +1,10 @@
 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 com.techcourse.dao.UserHistoryDao;
+import com.techcourse.domain.UserHistory;
+import java.sql.Connection;
 
 public class MockUserHistoryDao extends UserHistoryDao {
 
@@ -12,7 +13,10 @@ public MockUserHistoryDao(final JdbcTemplate jdbcTemplate) {
     }
 
     @Override
-    public void log(final UserHistory userHistory) {
-        throw new DataAccessException();
+    public void log(
+            final Connection connection,
+            final UserHistory userHistory
+    ) {
+        throw new DataAccessException("Mock exception for transaction test");
     }
 }

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

@@ -1,20 +1,18 @@
 package com.techcourse.service;
 
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+import com.interface21.dao.DataAccessException;
+import com.interface21.jdbc.core.JdbcTemplate;
 import com.techcourse.config.DataSourceConfig;
 import com.techcourse.dao.UserDao;
 import com.techcourse.dao.UserHistoryDao;
 import com.techcourse.domain.User;
 import com.techcourse.support.jdbc.init.DatabasePopulatorUtils;
-import com.interface21.dao.DataAccessException;
-import com.interface21.jdbc.core.JdbcTemplate;
 import org.junit.jupiter.api.BeforeEach;
-import org.junit.jupiter.api.Disabled;
 import org.junit.jupiter.api.Test;
 
-import static org.assertj.core.api.Assertions.assertThat;
-import static org.junit.jupiter.api.Assertions.assertThrows;
-
-@Disabled
 class UserServiceTest {
 
     private JdbcTemplate jdbcTemplate;
@@ -33,7 +31,7 @@ void setUp() {
     @Test
     void testChangePassword() {
         final var userHistoryDao = new UserHistoryDao(jdbcTemplate);
-        final var userService = new UserService(userDao, userHistoryDao);
+        final var userService = new UserService(userDao, userHistoryDao, DataSourceConfig.getInstance());
 
         final var newPassword = "qqqqq";
         final var createBy = "gugu";
@@ -48,7 +46,7 @@ void testChangePassword() {
     void testTransactionRollback() {
         // 트랜잭션 롤백 테스트를 위해 mock으로 교체
         final var userHistoryDao = new MockUserHistoryDao(jdbcTemplate);
-        final var userService = new UserService(userDao, userHistoryDao);
+        final var userService = new UserService(userDao, userHistoryDao, DataSourceConfig.getInstance());
 
         final var newPassword = "newPassword";
         final var createBy = "gugu";

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

@@ -36,6 +36,19 @@ public int update(
         return executeUpdate(sql, args);
     }
 
+    public int update(
+            final Connection connection,
+            final String sql,
+            final Object... args
+    ) {
+        try (final PreparedStatement ps = createPreparedStatement(connection, sql, args)) {
+            return ps.executeUpdate();
+        } catch (final SQLException e) {
+            log.error("데이터베이스 처리 중 예외 발생", e);
+            throw new DataAccessException(e);
+        }
+    }
+
     public <T> List<T> findAll(
             final String sql,
             final RowMapper<T> rowMapper,
@@ -103,6 +116,7 @@ private PreparedStatement createPreparedStatement(
             final String sql,
             final Object[] args
     ) throws SQLException {
+        validateParameterCount(sql, args);
         final PreparedStatement ps = con.prepareStatement(sql);
         log.debug("query : {}", sql);
         log.trace("parameters : {}", Arrays.toString(args));
@@ -111,4 +125,16 @@ private PreparedStatement createPreparedStatement(
         }
         return ps;
     }
+
+    private void validateParameterCount(
+            final String sql,
+            final Object[] args
+    ) {
+        final long placeholderCount = sql.chars()
+                .filter(ch -> ch == '?')
+                .count();
+        if (placeholderCount != args.length) {
+            throw new DataAccessException("SQL 파라미터 개수 불일치: ? %d개, 인자 %d개".formatted(placeholderCount, args.length));
+        }
+    }
 }

jdbc/src/test/java/com/interface21/jdbc/core/JdbcTemplateTest.java

@@ -227,4 +227,33 @@ void throwDataAccessExceptionOnSqlException() throws SQLException {
         assertThatThrownBy(() -> jdbcTemplate.findAll(sql, userRowMapper))
                 .isInstanceOf(DataAccessException.class);
     }
+
+    @DisplayName("SQL의 파라미터 개수와 인자의 개수가 다르면 예외를 던진다 - 인자가 부족할 때")
+    @Test
+    void validateParameterCountWithNotEnoughArgs() {
+        // given
+        final String sql = "UPDATE users SET password = ?, email = ? WHERE account = ?"; // 3 params
+        final String newPassword = "new_password";
+        final String account = "gugu"; // 2 args
+
+        // when & then
+        assertThatThrownBy(() -> jdbcTemplate.update(sql, newPassword, account))
+                .isInstanceOf(DataAccessException.class)
+                .hasMessage("SQL 파라미터 개수 불일치: ? 3개, 인자 2개");
+    }
+
+    @DisplayName("SQL의 파라미터 개수와 인자의 개수가 다르면 예외를 던진다 - 인자가 많을 때")
+    @Test
+    void validateParameterCountWithTooManyArgs() {
+        // given
+        final String sql = "UPDATE users SET password = ? WHERE account = ?"; // 2 params
+        final String newPassword = "new_password";
+        final String account = "gugu";
+        final String extraArg = "extra"; // 3 args
+
+        // when & then
+        assertThatThrownBy(() -> jdbcTemplate.update(sql, newPassword, account, extraArg))
+                .isInstanceOf(DataAccessException.class)
+                .hasMessage("SQL 파라미터 개수 불일치: ? 2개, 인자 3개");
+    }
 }

study/src/test/java/connectionpool/stage0/Stage0Test.java

@@ -41,7 +41,7 @@ void driverManager() throws SQLException {
      * 구현체는 각 vendor에서 제공한다.
      * 테스트 코드의 JdbcDataSource 클래스는 h2에서 제공하는 클래스다.
      *
-     * DirverManager가 아닌 DataSource를 사용하는 이유
+     * DriverManager가 아닌 DataSource를 사용하는 이유
      * - 애플리케이션 코드를 직접 수정하지 않고 properties로 디비 연결을 변경할 수 있다.
      * - 커넥션 풀링(Connection pooling) 또는 분산 트랜잭션은 DataSource를 통해서 사용 가능하다.
      *