jdbc连接Oracle

public static void main(String[] args) {
        //声明连接对象、执行sql对象、结果集对象
        Connection conn = null;
        PreparedStatement pre = null;
        ResultSet results  = null;
        //添加jar驱动
        try{
            //注册驱动
            Class.forName("oracle.jdbc.driver.OracleDriver");
            //获取连接数据库对象
            String url = "jdbc:oracle:thin:@127.0.0.1:1521:orcl";
            String name = "SCOTT";
            String pwd = "cpp123456";
            //DriverManage初始化时会扫描到注册的Driver实例
            conn = DriverManager.getConnection(url,name,pwd);
            System.out.println("连接成功");
            //定义要执行的sql
            String sql = "SELECT * FROM SCOTT.STUDENT";
            //获取执行sql对象
            pre = conn.prepareStatement(sql);
            //执行SQL并返回结果集
            results = pre.executeQuery();
            System.out.println("执行成功");
            while(results.next()){
                System.out.println("学生名:"+results.getString("STUDNETNAME"));
            }
        }catch (Exception  e){
            e.printStackTrace();
        }finally {
            try {
                if (results != null)
                    results.close();
                if (pre != null)
                    pre.close();
                if (conn != null)
                    conn.close();
                System.out.println("数据库连接已关闭！");
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
}