[1단계 - JDBC 라이브러리 구현하기] 베베(최원용) 미션 제출합니다.

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

@@ -10,6 +10,7 @@
 import java.sql.PreparedStatement;
 import java.sql.ResultSet;
 import java.sql.SQLException;
+import java.util.ArrayList;
 import java.util.List;
 
 public class UserDao {
@@ -27,27 +28,27 @@ public UserDao(final JdbcTemplate jdbcTemplate) {
     }
 
     public void insert(final User user) {
-        final var sql = "insert into users (account, password, email) values (?, ?, ?)";
+        final String sql = "insert into users (account, password, email) values (?, ?, ?)";
 
         Connection conn = null;
-        PreparedStatement pstmt = null;
+        PreparedStatement preparedStatement = null;
         try {
             conn = dataSource.getConnection();
-            pstmt = conn.prepareStatement(sql);
+            preparedStatement = conn.prepareStatement(sql);
 
             log.debug("query : {}", sql);
 
-            pstmt.setString(1, user.getAccount());
-            pstmt.setString(2, user.getPassword());
-            pstmt.setString(3, user.getEmail());
-            pstmt.executeUpdate();
+            preparedStatement.setString(1, user.getAccount());
+            preparedStatement.setString(2, user.getPassword());
+            preparedStatement.setString(3, user.getEmail());
+            preparedStatement.executeUpdate();
         } catch (SQLException e) {
             log.error(e.getMessage(), e);
             throw new RuntimeException(e);
         } finally {
             try {
-                if (pstmt != null) {
-                    pstmt.close();
+                if (preparedStatement != null) {
+                    preparedStatement.close();
                 }
             } catch (SQLException ignored) {}
 
@@ -60,25 +61,82 @@ public void insert(final User user) {
     }
 
     public void update(final User user) {
-        // todo
+        Connection connection = null;
+        PreparedStatement preparedStatement = null;
+        try {
+            connection = dataSource.getConnection();
+            final String sql = "update users set account=?, password=?, email=? where id=?";
+            preparedStatement = connection.prepareStatement(sql);
+            preparedStatement.setString(1, user.getAccount());
+            preparedStatement.setString(2, user.getPassword());
+            preparedStatement.setString(3, user.getEmail());
+            preparedStatement.setLong(4, user.getId());
+            preparedStatement.executeUpdate();
+        } catch (SQLException e) {
+            log.error(e.getMessage(), e);
+            throw new RuntimeException(e);
+        } finally {
+            try {
+                if (preparedStatement != null) {
+                    preparedStatement.close();
+                }
+            } catch (SQLException ignored) {}
+
+            try {
+                if (connection != null) {
+                    connection.close();
+                }
+            } catch (SQLException ignored) {}
+        }
     }
 
     public List<User> findAll() {
-        // todo
-        return null;
+        Connection connection = null;
+        PreparedStatement preparedStatement = null;
+        try {
+            connection = dataSource.getConnection();
+            final String sql = "select * from users";
+            preparedStatement = connection.prepareStatement(sql);
+            final ResultSet resultSet = preparedStatement.executeQuery();
+
+            final List<User> users = new ArrayList<>();
+            while (resultSet.next()) {
+                final Long id = resultSet.getLong("id");
+                final String account = resultSet.getString("account");
+                final String password = resultSet.getString("password");
+                final String email = resultSet.getString("email");
+                users.add(new User(id, account, password, email));
+            }
+            return users;
+        } catch (SQLException e) {
+            log.error(e.getMessage(), e);
+            throw new RuntimeException(e);
+        } finally {
+            try {
+                if (preparedStatement != null) {
+                    preparedStatement.close();
+                }
+            } catch (SQLException ignored) {}
+
+            try {
+                if (connection != null) {
+                    connection.close();
+                }
+            } catch (SQLException ignored) {}
+        }
     }
 
     public User findById(final Long id) {
         final var sql = "select id, account, password, email from users where id = ?";
 
         Connection conn = null;
-        PreparedStatement pstmt = null;
+        PreparedStatement preparedStatement = null;
         ResultSet rs = null;
         try {
             conn = dataSource.getConnection();
-            pstmt = conn.prepareStatement(sql);
-            pstmt.setLong(1, id);
-            rs = pstmt.executeQuery();
+            preparedStatement = conn.prepareStatement(sql);
+            preparedStatement.setLong(1, id);
+            rs = preparedStatement.executeQuery();
 
             log.debug("query : {}", sql);
 
@@ -101,8 +159,8 @@ public User findById(final Long id) {
             } catch (SQLException ignored) {}
 
             try {
-                if (pstmt != null) {
-                    pstmt.close();
+                if (preparedStatement != null) {
+                    preparedStatement.close();
                 }
             } catch (SQLException ignored) {}
 
@@ -115,7 +173,38 @@ public User findById(final Long id) {
     }
 
     public User findByAccount(final String account) {
-        // todo
+        Connection connection = null;
+        PreparedStatement preparedStatement = null;
+        try {
+            connection = dataSource.getConnection();
+            final String sql = "select * from users where account = ?";
+            preparedStatement = connection.prepareStatement(sql);
+            preparedStatement.setString(1, account);
+            final ResultSet resultSet = preparedStatement.executeQuery();
+
+            while (resultSet.next()) {
+                final Long id = resultSet.getLong("id");
+                final String password = resultSet.getString("password");
+                final String email = resultSet.getString("email");
+                return new User(id, account, password, email);
+            }
+        } catch (SQLException e) {
+            log.error(e.getMessage(), e);
+            throw new RuntimeException(e);
+        } finally {
+            try {
+                if (preparedStatement != null) {
+                    preparedStatement.close();
+                }
+            } catch (SQLException ignored) {}
+
+            try {
+                if (connection != null) {
+                    connection.close();
+                }
+            } catch (SQLException ignored) {}
+        }
         return null;
     }
+
 }

app/src/main/java/com/techcourse/support/jdbc/init/DatabasePopulatorUtils.java

@@ -6,6 +6,7 @@
 import javax.sql.DataSource;
 import java.io.File;
 import java.io.IOException;
+import java.net.URL;
 import java.nio.file.Files;
 import java.sql.Connection;
 import java.sql.SQLException;
@@ -19,9 +20,10 @@ public static void execute(final DataSource dataSource) {
         Connection connection = null;
         Statement statement = null;
         try {
-            final var url = DatabasePopulatorUtils.class.getClassLoader().getResource("schema.sql");
-            final var file = new File(url.getFile());
-            final var sql = Files.readString(file.toPath());
+            final URL url = DatabasePopulatorUtils.class.getClassLoader().getResource("schema.sql");
+            final File file = new File(url.getFile());
+            final String sql = Files.readString(file.toPath());
+
             connection = dataSource.getConnection();
             statement = connection.createStatement();
             statement.execute(sql);

app/src/test/java/com/techcourse/dao/UserDaoTest.java

@@ -6,6 +6,8 @@
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
+import java.sql.SQLException;
+
 import static org.assertj.core.api.Assertions.assertThat;
 
 class UserDaoTest {
@@ -17,7 +19,7 @@ void setup() {
         DatabasePopulatorUtils.execute(DataSourceConfig.getInstance());
 
         userDao = new UserDao(DataSourceConfig.getInstance());
-        final var user = new User("gugu", "password", "[email protected]");
+        final User user = new User("gugu", "password", "[email protected]");
         userDao.insert(user);
     }
 

study/src/test/java/connectionpool/stage1/Stage1Test.java

@@ -26,17 +26,31 @@ class Stage1Test {
      * Connection Pooling and Statement Pooling
      * https://docs.oracle.com/en/java/javase/11/docs/api/java.sql/javax/sql/package-summary.html
      */
+
+    // 여기서 드는 의문
+    // 미리 만들어둔 커넥션은 재사용이 가능하니,
+    // 미리 만들지 않았을 때는 초기 연결만 느리고,
+    // 데이터베이스 최대 커넥션만큼 다 만들어 졌을 때는
+    // 미리 커넥션을 만들어 둔 것과 비교해서 차이가 있는가?
+    // (나는 없을 것 같다고 생각한다.)
     @Test
     void testJdbcConnectionPool() throws SQLException {
         final JdbcConnectionPool jdbcConnectionPool = JdbcConnectionPool.create(H2_URL, USER, PASSWORD);
 
+        // 커넥션이 미리 만들어져 있지 않음을 검증한다.
         assertThat(jdbcConnectionPool.getActiveConnections()).isZero();
+
+        // 커넥션 풀에서 커넥션을 꺼내온다.
         try (final var connection = jdbcConnectionPool.getConnection()) {
+            // 꺼내온 커넥션이 유효한 커넥션인가?
             assertThat(connection.isValid(1)).isTrue();
+            // 꺼내온 커넥션이 활성 상태인가?
             assertThat(jdbcConnectionPool.getActiveConnections()).isEqualTo(1);
         }
+        // 커넥션 풀에 활성 상태인 커넥션이 없는가?
         assertThat(jdbcConnectionPool.getActiveConnections()).isZero();
 
+        // 커넥션 풀 닫기
         jdbcConnectionPool.dispose();
     }
 
@@ -65,6 +79,7 @@ void testHikariCP() {
         hikariConfig.setUsername(USER);
         hikariConfig.setPassword(PASSWORD);
         hikariConfig.setMaximumPoolSize(5);
+
         hikariConfig.addDataSourceProperty("cachePrepStmts", "true");
         hikariConfig.addDataSourceProperty("prepStmtCacheSize", "250");
         hikariConfig.addDataSourceProperty("prepStmtCacheSqlLimit", "2048");

study/src/test/java/connectionpool/stage2/Stage2Test.java

@@ -50,9 +50,12 @@ void test() throws InterruptedException {
         }
 
         // 동시에 많은 요청이 몰려도 최대 풀 사이즈를 유지한다.
+        System.out.println("hikariPool.getTotalConnections() = " + hikariPool.getTotalConnections());
+        System.out.println("DataSourceConfig.MAXIMUM_POOL_SIZE = " + DataSourceConfig.MAXIMUM_POOL_SIZE);
         assertThat(hikariPool.getTotalConnections()).isEqualTo(DataSourceConfig.MAXIMUM_POOL_SIZE);
 
         // DataSourceConfig 클래스에서 직접 생성한 커넥션 풀.
+        System.out.println("hikariDataSource.getPoolName() = " + hikariDataSource.getPoolName());
         assertThat(hikariDataSource.getPoolName()).isEqualTo("gugu");
     }