留言板代码.doc

package to;import java.io.IOException;import java.io.PrintWriter;import java.sql.DriverManager;import java.sql.ResultSet;import java.sql.SQLException;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import com.mysql.jdbc.Connection;import com.mysql.jdbc.Statement;public class gh extends HttpServlet String name;String message;static int count =0; /记数static String Message = ;/保存留言public void doPost(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException response.setContentType(text/html);response.setCharacterEncoding(GB2312);PrintWriter out = response.getWriter();String getMsg = Message; /获取之前的留言/获取用户名 name = new String(request.getParameter(name).getBytes(ISO8859_1),GB2312);/获取留言String message = new String(request.getParameter(message).getBytes(ISO8859_1),GB2312);count+; /计数器自增tryConnection con;Statement stmt;ResultSet rs;/加载驱动程序，下面的代码为加载MySQL驱动程序Class.forName(com.mysql.jdbc.Driver);/注册MySQL驱动程序DriverManager.registerDriver(new com.mysql.jdbc.Driver();/用适当的驱动程序连接到数据库String dbUrl = jdbc:mysql:/23:3306/LY1?useUnicode=true&characterEncoding=GB2312&charset=gb2312; String dbUser=dbuser;String dbPwd=1234;/建立数据库连接con = (Connection) java.sql.DriverManager.getConnection(dbUrl,dbUser,dbPwd);/创建一个JDBC声明stmt = (Statement) con.createStatement();/增加新记录stmt.executeUpdate(INSERT INTO pt1 (id,name,description) VALUES ( + count + , + name + , + message + );/查询记录rs = stmt.executeQuery(SELECT id,name,description from pt1);/输出查询结果out.println();while (rs.next()String col1 = rs.getString(1);/String col2 = new String(rs.getString(2).getBytes(GB2312),ISO8859_1);String col2 = rs.getString(2);String col3 = rs.getString(3);/String col3 = new String(rs.getString(3).getBytes(GB2312),ISO8859_1);/打印所显示的数据Message = 第+col1+楼：姓名：+col2+留言：+col3+;out.print(Message); /打印留言out.println(+col1+col2+col3+);/关闭数据库连结rs.close();stmt.close();con.close();/捕获错误信息catch (Exception e) out.println(e.getMessage(); Message = 第+count+楼：姓名：+name+留言：+message+;/*if(count1)/留言加载Message = 第