正确书写事务代码

  public static void main(String[] args) {
       Connection conn = null;
       Statement stmt = null;
       try {
           // 动态导入数据库的驱动
           Class.forName("com.mysql.jdbc.Driver"); 
           // 获取数据库链接
           conn = DriverManager.getConnection(
                  "jdbc:mysql://localhost:3306/employee", "root", "wang314159");          
           // 开启事务
           //不把其设置为true之前都是一个当作一个事务来处理
           conn.setAutoCommit( false );
 
           // 创造SQL语句
           String sql = "INSERT INTO myrollback ( name,age,address,school ) VALUES ( 'test', 22,'大立即','hdu' )";           
           String sql2 = "INSERT INTO myrollback ( name,age,address,school ) VALUES ( 'test_Name', '33','大立即','hdu' ,'test')";
           // 执行SQL语句
           stmt = conn.createStatement();
           stmt.executeUpdate(sql);
           stmt.executeUpdate(sql2);
           // 提交事务
           conn.commit();
           System.out.println( "OK!" );
       } catch (Exception e) {
           e.printStackTrace();
           System.out.println("有错误！");
          
           try {
          // 回滚事务
          //撤销上面对事务的所有操作哈！
              conn.rollback();
           } catch ( Exception e2 ) {}
       } finally {
           // 关闭Statement
           try {
              stmt.close();
           } catch (Exception e) {}
           // 关闭Connection
           try {
              conn.close();
           } catch (Exception e) {}
       }
    }
}