JDBC依然是一个Java工程师必备的基本功

喜欢ヅ旅行 2024-03-30 13:11 88阅读 0赞

#### 1.基本逻辑实现 ####

#### public static void JDBCmysqlDemo() \{   // 1. 实例化资源   // 1.1 注册JDBC驱动   Class.forName("com.mysql.cj.jdbc.Driver");   // 1.2 创建数据库连接实例   String url = "jdbc:mysql://localhost:3306/database?useSSL=false&useUnicode=true&characterEncoding=UTF-8&serverTimezone=Asia/Shanghai";   String user = "root";   String pswd = "root";   Connection conn = DriverManager.getConnection(url, user, pswd); ####

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#### 2.完整代码实现   public static void JDBCmysql2() \{   Connection conn = null; ####

#### try \{   // 1. 实例化资源   // 1.1 注册JDBC驱动   Class.forName("com.mysql.cj.jdbc.Driver");   // 1.2 创建数据库连接实例   String url = "jdbc:mysql://localhost:3306/database?useSSL=false&useUnicode=true&characterEncoding=UTF-8&serverTimezone=Asia/Shanghai";   String user = "root";   String pswd = "root";   conn = DriverManager.getConnection(url, user, pswd); ####

#### // 2. 查询对象   // 2.1 实例话查询声明，以及查询语句   Statement st = conn.createStatement();   String query = "select \* from table1";   ResultSet rs = st.executeQuery(query);   // 2.2. 查询结果   while (rs.next()) \{   int uid = rs.getInt(1);   System.out.println(uid);   \}   \} catch (ClassNotFoundException | SQLException e) \{   throw new RuntimeException(e);   \} finally \{   // 3. 关闭连接，释放资源   try \{   if (conn != null & !conn.isClosed()) \{   conn.close();   \}   \} catch (SQLException e) \{   throw new RuntimeException(e);   \}   \} ####

#### \}      3.防SQL注入攻击      public static void JDBCDemo () \{   Connection conn = null; ####

#### // 2. 查询对象   // 2.1 实例话查询声明，以及查询语句   String query = "select \* from table1";   PreparedStatement st = conn.prepareStatement(query);   ResultSet rs = st.executeQuery(query);   // 2.2. 查询结果   while (rs.next()) \{   int uid = rs.getInt(1);   System.out.println(uid);   \}   \} catch (ClassNotFoundException | SQLException e) \{   throw new RuntimeException(e);   \} finally \{   // 3. 关闭连接，释放资源   try \{   if (conn != null & !conn.isClosed()) \{   conn.close();   \}   \} catch (SQLException e) \{   throw new RuntimeException(e);   \}   \} ####

#### \} ####