<%@ page contentType="text/html; charset=gb2312" %>            <%@ page language="java" %>            <%@ page import="com.mysql.jdbc.Driver" %>            <%@ page import="java.sql.*" %>            <%            //驱动程序名            String driverName="com.mysql.jdbc.Driver";            //数据库用户名            String userName="cl41";            //密码            String userPasswd="123456";            //数据库名            String dbName="db";            //表名            String tableName="dbtest";            //联结字符串            String url="jdbc:mysql://localhost/"+dbName+"?user="+userName+"&password="+userPasswd;            Class.forName("com.mysql.jdbc.Driver").newInstance();            Connection connection=DriverManager.getConnection(url);            Statement statement = connection.createStatement();            String sql="SELECT * FROM "+tableName;            ResultSet rs = statement.executeQuery(sql);            //获得数据结果集合            ResultSetMetaData rmeta = rs.getMetaData();            //确定数据集的列数，亦字段数            int numColumns=rmeta.getColumnCount();            // 输出每一个数据值            out.print("id");            out.print("|");            out.print("num");            out.print("<br>");            while(rs.next()) {            out.print(rs.getString(1)+" ");            out.print("|");            out.print(rs.getString(2));            out.print("<br>");            }            out.print("<br>");            out.print("数据库操作成功，恭喜你");            rs.close();            statement.close();            connection.close();            %>