servlet的增删改查

这是一个简单的servlet增删改查界面

t3.sql数据库：

/*SQLyog 企业版 - MySQL GUI v8.14 MySQL - 5.5.25a : Database - test**********************************************************************//*!40101 SET NAMES utf8 */;/*!40101 SET SQL_MODE=''*/;/*!40014 SET @OLD_UNIQUE_CHECKS=@@UNIQUE_CHECKS, UNIQUE_CHECKS=0 */;/*!40014 SET @OLD_FOREIGN_KEY_CHECKS=@@FOREIGN_KEY_CHECKS, FOREIGN_KEY_CHECKS=0 */;/*!40101 SET @OLD_SQL_MODE=@@SQL_MODE, SQL_MODE='NO_AUTO_VALUE_ON_ZERO' */;/*!40111 SET @OLD_SQL_NOTES=@@SQL_NOTES, SQL_NOTES=0 */;CREATE DATABASE /*!32312 IF NOT EXISTS*/`test` /*!40100 DEFAULT CHARACTER SET utf8 */;USE `test`;/*Table structure for table `t3` */DROP TABLE IF EXISTS `t3`;CREATE TABLE `t3` (  `id` int(11) NOT NULL AUTO_INCREMENT,  `password` varchar(32) DEFAULT NULL,  `userName` varchar(32) DEFAULT NULL,  `sex` varchar(5) DEFAULT NULL,  `age` int(2) DEFAULT NULL,  `address` varchar(1024) DEFAULT NULL,  PRIMARY KEY (`id`)) ENGINE=InnoDB AUTO_INCREMENT=50 DEFAULT CHARSET=utf8;/*Data for the table `t3` */insert  into `t3`(`id`,`password`,`userName`,`sex`,`age`,`address`) values (1,'23','123','女',12,' '),(36,'5345423','李四','男',12,'沙河'),(37,'654321','admin','男',30,'中国北京'),(38,'123456','admin2','女',28,'中国北京'),(39,'654321','admin','男',29,'中国河北'),(40,'123456','admin3','男',29,'中国河北'),(41,'12345678','admin4','男',29,'中国河北'),(42,'123','张三','男',22,'中国'),(43,'12345','王五','男',32,'山东济南'),(44,'123456','老刘','男',33,'中国河南'),(45,'654321','老刘','男',33,'中国河南'),(46,'123','老王','男',33,'中国河南'),(48,'12345678','老八','男',21,'234'),(49,'456123','admin','女',21,'123456');/*!40101 SET SQL_MODE=@OLD_SQL_MODE */;/*!40014 SET FOREIGN_KEY_CHECKS=@OLD_FOREIGN_KEY_CHECKS */;/*!40014 SET UNIQUE_CHECKS=@OLD_UNIQUE_CHECKS */;/*!40111 SET SQL_NOTES=@OLD_SQL_NOTES */;

servletAction.java源代码：

package com.action;import java.io.IOException;import java.io.PrintWriter;import java.io.UnsupportedEncodingException;import java.util.List;import java.util.Map;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import com.service.stuInfoService;@SuppressWarnings("serial")public class servletAction extends HttpServlet {//导入service服务包stuInfoService stuinfoService=new stuInfoService();//影响行数默认为-1，因为数据操作后的返回结果不为-1private int i=-1;//创建list数组private List list=null;//设定初始状态private boolean state=false;/* * servlet action * */public servletAction() {super();}/* * servlet销毁方法 * */public void destroy() {super.destroy(); // Just puts "destroy" string in log// Put your code here}/* * doGet方法 * */public void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {//如果是get方法，自动带参数跳转到post()方法doPost(request, response);}/* * doPost()方法 * */public void doPost(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {//设置页面编码格式为utf-8request.setCharacterEncoding("utf-8");response.setCharacterEncoding("utf-8");//获取页面路径请求参数actionString action=request.getParameter("action");//根据页面路径请求参数判断应该跳转的页面if(action.equals("insert")){//跳转到插入页面insert(request,response);}else if(action.equals("delete")){//跳转到删除页面delete(request,response);}else if(action.equals("update")){//跳转到修改页面update(request,response);}else if(action.equals("select")){//跳转到查询页面select(request,response);}}/* * 查询方法 * */private void select(HttpServletRequest request, HttpServletResponse response) throws UnsupportedEncodingException,ServletException, IOException {// TODO Auto-generated method stub//设置页面编码格式为utf-8request.setCharacterEncoding("utf-8");response.setCharacterEncoding("utf-8");System.out.println("这里是查询方法！");//获取页面请求参数String userName=request.getParameter("userName");String password=request.getParameter("password");String sex=request.getParameter("sex");String age=request.getParameter("age");String address=request.getParameter("address");//判断性别是否则”请选择“，如果是则置空，因为性别中只有”男“，”女“，没有”请选择“if("请选择".equals(sex)){sex="";System.out.println("sex:"+sex);}//在控制台打印出来页面传递过来的参数System.out.println("userName:"+userName+"   password："+password+"   sex："+sex+"   age："+age+"   address："+address);//穿点String数组，方便参数调用String[] keyOption=new String[]{"userName","password","sex","age","address"};String[] valOption=new String[]{userName,password,sex,age,address};//循环遍历页面参数for(int i=0;i<valOption.length;i++){//判断页面传递来的参数是否存在，如果不存在则置空if(null==valOption[i]){valOption[i]="";}}//查询方法，获取mysql数据库的返回结果数组list=stuinfoService.select(keyOption,valOption);//将servlet获取的查询结果打印到控制台System.out.println("姓名"+"     密码"+"     性别"+"     年龄"+"     地址");//判断获取的来自mysql数据库的数组是否存在if(list!=null){//判断list数组是否为空if(list.size()>0){//循环遍历list数组for(int i=0;i<list.size();i++){//创建Map数组接受list传递来的每一行参数Map<String,String> map=(Map<String, String>) list.get(i);//在控制台打印出每一行数组System.out.println(map.get("userName")+"  "+map.get("password")+"  "+map.get("sex")+"  "+map.get("age")+"  "+map.get("address"));}}else{System.out.println("这里是select()方法，list数组为空！");}}else{System.out.println("这里是select()方法，list数组不存在！");}//将查询结果打印到前台界面response.setContentType("text/html");PrintWriter out = response.getWriter();out.println("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">");out.println("<HTML>");out.println("  <HEAD><TITLE>Select Servlet</TITLE></HEAD>");out.println("  <BODY>");out.println("<table>");//在servlet页面打印出每一行的航标题out.println("<tr>  <th>姓名</th>  <th>密码</th>  <th>性别</th>  <th>年龄</th>   <th>地址</th>  </tr>");//判断list数组是否存在if(list!=null){//判断list数组是否为空if(list.size()>0){//循环遍历list数组for(int i=0;i<list.size();i++){//创建Map容器接收list传递来的每一行参数Map<String,String> map=(Map<String, String>) list.get(i);//打印出每一行的结果out.println("<tr>");out.println("<th>");out.println(map.get("userName"));out.println("</th>");out.println("<th>");out.println(map.get("password"));out.println("</th>");out.println("<th>");out.println(map.get("sex"));out.println("</th>");out.println("<th>");out.println(map.get("age"));out.println("</th>");out.println("<th>");out.println(map.get("address"));out.println("</th>");out.println("</tr>");}}else{System.out.println("这里是select()方法，list数组为空！");}}else{System.out.println("这里是select()方法，list数组不存在！");}out.println("</table>");out.println("  </BODY>");out.println("</HTML>");out.flush();out.close();}/* * 修改方法 * */private void update(HttpServletRequest request, HttpServletResponse response) throws UnsupportedEncodingException,ServletException, IOException {// TODO Auto-generated method stub//设置页面编码格式为utf-8request.setCharacterEncoding("utf-8");response.setCharacterEncoding("utf-8");System.out.println("这里是update方法");//获取页面请求参数String userName=request.getParameter("userName");String upOption=request.getParameter("upOption");String upValue=request.getParameter("upValue");//在控制台打印出获取的页面参数System.out.println("userName:"+userName+"   upOption:"+upOption+"   upValue:"+upValue);//判断upOption是否为”请选择“if("请选择".equals(upOption)){//如果参数是”请选择“，则认为没有任何参数，所以说不进行任何操作，自动返回原始页面response.sendRedirect("index.jsp");}else{//判断upValue参数是否存在if(upValue!=null){//判断upValue参数是否为空if("".equals(upValue)){//如果为空，不进行任何操作，直接返回原始页面response.sendRedirect("index.jsp");System.out.println("upValue参数为空！");}else{//将获取的下拉列表汉语信息转换成对应的字符串if("姓名".equals(upOption)){upOption="userName";}else if("密码".equals(upOption)){upOption="password";}else if("性别".equals(upOption)){upOption="sex";}else if("年龄".equals(upOption)){upOption="age";}else if("地址".equals(upOption)){upOption="address";}//在控制台打印出转换参数后的结果System.out.println("userName:"+userName+"   upOption:"+upOption+"   upValue:"+upValue);//执行修改数据库操作，返回影响行数i=stuinfoService.update(userName,upOption,upValue);//根据返回的影响行数判断数据是否插入成功if(i!=-1){System.out.println("这里是update()方法，数据修改成功！");}else{System.out.println("这里是update()方法，数据修改失败！");}//修改后自动跳转到查询方法，方便自己查看修改的参数结果response.sendRedirect("servletAction?action=select");}}else{//如果不存在，不进行任何操作，直接返回原始页面response.sendRedirect("index.jsp");System.out.println("upValue参数并不存在！");}}}/* * 数据删除方法 * */private void delete(HttpServletRequest request, HttpServletResponse response) throws UnsupportedEncodingException,ServletException, IOException {// TODO Auto-generated method stubSystem.out.println("这里是删除方法！");//这只页面编码格式request.setCharacterEncoding("utf-8");response.setCharacterEncoding("utf-8");//获取页面请求参数String delOption=request.getParameter("delOption");String delValue=request.getParameter("delValue");//打印获取的页面请求参数System.out.println("delOption:"+delOption+"      delValue:"+delValue);//将jsp页面传来的参数转换成与数据库对应的参数if("id".equals(delOption)){delOption="id";}else if("姓名".equals(delOption)){delOption="userName";}else if("密码".equals(delOption)){delOption="password";}else if("性别".equals(delOption)){delOption="sex";}else if("年龄".equals(delOption)){delOption="age";}else if("地址".equals(delOption)){delOption="address";}//其实以前我创建的是Object，但是后来为了方便对sql语句的拼接，所以就改成了String类型，所以说这里用哪种都是一样能用的String deleteOption=delOption;String deleteValue=delValue;//打印对应的Object或者是StringSystem.out.println("deleteOption:"+deleteOption+"   deleteValue:"+deleteValue);//执行删除方法，获取影响行数i=stuinfoService.delete(deleteOption,deleteValue);//判断数据是否删除成功if(i!=-1){System.out.println("这里是delete()方法，数据删除成功！");}else{System.out.println("这里是delete()方法，数据删除失败！");}//删除后自动跳转到查询方法，方便对于删除结果的查看response.sendRedirect("servletAction?action=select");}/* * 插入方法 * */private void insert(HttpServletRequest request, HttpServletResponse response) throws UnsupportedEncodingException,ServletException, IOException,NullPointerException {// TODO Auto-generated method stub//设置页面编码格式为utf-8request.setCharacterEncoding("utf-8");response.setCharacterEncoding("utf-8");System.out.println("这里是插入界面！");//获取页面请求参数String userName=request.getParameter("userName");String password=request.getParameter("password");String sex=request.getParameter("sex");String age=request.getParameter("age");String address=request.getParameter("address");//判断userName是否存在if(userName!=null){//判断userName是否为空if("".equals(userName)){state=true;}}else{state=true;}//判断password是否存在        if(password!=null){        //判断password是否为空if("".equals(password)){state=true;}}else{state=true;}                //判断sex是否存在        if(sex!=null){        //判断sex是否为空if("".equals(sex)){state=true;}}else{state=true;}                //判断age是否存在        if(age!=null){        //判断age是否为空if("".equals(age)){state=true;}}else{state=true;}        //判断address是否存在        if(address!=null){        //判断address是否为空if("".equals(address)){state=true;}}else{state=true;}/*//判断插入的数据是否存在if((userName!=null)&&(password!=null)&&(sex!=null)&&(age!=null)&&(address!=null)){//判断插入的数据是否为空if(("".equals(userName))&&("".equals(password))&&("".equals(sex))&&("".equals(age))&&("".equals(address))){//改变状态state=true;}}else{//改变状态state=true;}*/                if("true".equals(state)){                response.sendRedirect("index.jsp");                }else{                //在控制台打印页面请求参数    System.out.println("userName:"+userName+"   password:"+password+"   sex:"+sex+"   age:"+age+"   address:"+address);                }//在控制台打印页面请求参数System.out.println("userName:"+userName+"   password:"+password+"   sex:"+sex+"   age:"+age+"   address:"+address);//创建String[]数组，接受页面传递的参数String[] object=new String[]{userName,password,sex,age,address};//判断参数是否存在if(object!=null){//判断参数是否为空if(object.length>0){/*//循环遍历object中的每一个元素//目的就是将插入的不完善信息筛选出来for(int i=0;i<object.length;i++){//判断每一个元素是否存在if(object[i]!=null){//判断每一个元素是否为空if("".equals(object[i])){//改变state状态为truestate=true;}}else{//改变state状态为truestate=true;}}*/if("true".equals(state)){//说明插入信息不全，不进行任何操作，直接返回原始页面response.sendRedirect("index.jsp");}else{//执行插入方法，返回影响行数i=stuinfoService.insert(object);//根据影响行数判断数据是否插入成功if(i!=-1){System.out.println("这里是insert()方法，数据插入成功！");}else{System.out.println("这里是insert()方法，数据插入失败！");}//删除后自动跳转到查询方法，方便查看删除结果response.sendRedirect("servletAction?action=select");}}else{//不进行任何操作，直接返回原始页面response.sendRedirect("index.jsp");System.out.println("这里是insert()方法，object为空数组！");}}else{//不进行任何操作，直接返回原始页面response.sendRedirect("index.jsp");System.out.println("这里是insert()方法，object数组不存在！");}}//servlet的初始化public void init() throws ServletException {// Put your code here}}

mySqlConnection.java源代码：

package com.dbdao.mysql;import java.sql.Connection;import java.sql.DriverManager;import java.sql.PreparedStatement;import java.sql.ResultSet;import java.sql.SQLException;import org.junit.Test;public class mySqlConnection {//创建数据库驱动名称private static String Driver_class="com.mysql.jdbc.Driver";//数据库链接地址private String url="jdbc:mysql://localhost:3306/test";//数据库用户名private String user="root";//数据库密码private String password="11";//数据库链接private Connection con=null;//准备声明sql语句private PreparedStatement pstmt=null;//结果集private ResultSet rs=null;//影响行数private int i;/* * 创建驱动 * */static{try {Class.forName(Driver_class);} catch (ClassNotFoundException e) {// TODO Auto-generated catch blocke.printStackTrace();}}/* * 加载驱动 * */@Testpublic void getConnect() {// TODO Auto-generated method stubtry {con=DriverManager.getConnection(url, user, password);} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}//判断数据库是否加载成功if(con!=null){System.out.println("数据库加载成功！");}else{System.out.println("数据库加载失败！");}}/* * 执行sql语句 * */public void doSql(String sql,Object[] object) {// TODO Auto-generated method stub//判断sql语句是否存在if(sql!=null){//加载驱动getConnect();//判断object数组是否存在if(object==null){//如果不存在，创建一个，防止出现空指针异常object=new Object[0];}try {//声明一条准备的sql语句pstmt=con.prepareStatement(sql);//为Object对象一一赋值for(int i=0;i<object.length;i++){pstmt.setObject(i+1, object[i]);}//执行声明的sql语句pstmt.execute();} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}}else{System.out.println("sql语句并不存在！");}}/* * 获取结果集 * */public ResultSet getRS(){try {//获取结果集方法rs=pstmt.getResultSet();} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}//返回结果集return rs;}/* * 获取影响行数 * */public int getUpdateCount() {// TODO Auto-generated method stubtry {//获取影响行数方法i=pstmt.getUpdateCount();} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}//返回影响行数return i;}/* * 关闭方法 * */public void getClose() {// TODO Auto-generated method stub//关闭结果集try {//结果集关闭方法if(rs!=null){rs.close();}} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}finally{//关闭声明的sql语句try {//关闭声明的sql语句方法if(pstmt!=null){pstmt.close();}} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}finally{//卸载驱动try {//驱动卸载方法if(con!=null){con.close();}} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}}}}}

stuInfoService.java源代码：

package com.service;import java.sql.ResultSet;import java.sql.SQLException;import java.util.ArrayList;import java.util.HashMap;import java.util.List;import java.util.Map;import org.junit.Test;import com.dbdao.mysql.mySqlConnection;public class stuInfoService {//导入mySqlConnection类mySqlConnection mysqlCon=new mySqlConnection();//准备sql语句private String sql;//影响行数（数据变更后，影响行数都是大于0，等于0时没变更，所以说如果变更失败，那么影响行数必定为负）private int i=-1;//结果集private ResultSet rs;//创建list数组private List list=null;//判断状态private boolean state=false;/* * 插入方法 * */@Testpublic int insert(String[] object) {// TODO Auto-generated method stub//创建sql语句sql="insert into t3 (userName,password,sex,age,address) values(?,?,?,?,?) ";//判断Object数组是否存在if(object!=null){//判断Object数组是否为空if(object.length>0){//执行插入方法mysqlCon.doSql(sql, object);}else{System.out.println("object是空数组！");}}else{System.out.println("object数组不存在！");}//获取影响行数i=mysqlCon.getUpdateCount();//判断是否插入成功if(i!=-1){System.out.println("数据插入成功！");}else{System.out.println("数据插入失败！");}//关闭链接mysqlCon.getClose();//返回影响行数return i;}/* * 删除数据 * */public int delete(String deleteOption, String deleteValue) {// TODO Auto-generated method stub//创建sql语句sql="delete from t3 where "+deleteOption+"="+"'"+deleteValue+"' ";//在控制台打印拼接的sql语句System.out.println("sql语句为："+sql);//执行sql语句mysqlCon.doSql(sql, null);//获取影响行数i=mysqlCon.getUpdateCount();//判断数据是否插入成功if(i!=-1){System.out.println("数据删除成功！");}else{System.out.println("数据删除失败！");}//关闭链接mysqlCon.getClose();//返回影响行数return i;}/* * 更新数据 * */@Testpublic int update(String userName, String upOption, String upValue) {// TODO Auto-generated method stub//创建sql语句sql="update t3 set "+upOption+"="+"'"+upValue+"'"+" where userName="+"'"+userName+"'";//在控制台打印拼接的sql语句System.out.println("sql语句为："+sql);//执行sql语句mysqlCon.doSql(sql, null);//获取影响行数i=mysqlCon.getUpdateCount();//判断数据是否更新成功if(i!=-1){System.out.println("数据更新成功！");}else{System.out.println("数据更新失败！");}//关闭链接mysqlCon.getClose();//返回影响行数return i;}/* * 遍历数据 * */@SuppressWarnings("unchecked")@Testpublic List select(String[] keyOption, String[] valOption) {// TODO Auto-generated method stub//创建String字符串，用于拼接sql的条件语句        String condition="";        //循环遍历keyOption数组for(int i=0;i<keyOption.length;i++){//判断valOption[i]是否存在            if(valOption[i].length()>0){            //拼接sql的条件语句condition=condition+keyOption[i]+"="+"'"+valOption[i]+"'"+" and ";//在控制台逐条打印sql的条件语句System.out.println(condition);}}//拼接完成的sql条件语句System.out.println("语句的拼接结果："+condition);//判断condition是否为空if(condition.length()>0){//剪切拼接的sql条件语句condition=condition.substring(0,condition.length()-4);}//在控制台打印出来剪切后的sql的条件拼接语句System.out.println("剪切后的condition语句为:"+condition);//继续拼接成完整的sql语句        sql="select * from t3 where "+condition;        //在控制台打印出来拼接的完整语句System.out.println("完整的sql语句为："+sql);//循环遍历valOption数组for(int i=0;i<valOption.length;i++){//判断valOption[i]元素是否为空if(valOption[i].length()>0){//如果不为空则将状态置为truestate=true;}}//判断状态if(true==state){//如果为TRUE则不进行任何操作sql=sql;}else{//如果为false则将sql语句置换成新语句sql="select * from t3";}//在控制台打印出最适合的sql语句System.out.println("适合的sql语句为："+sql);//执行sql语句mysqlCon.doSql(sql, null);//获取结果集rs=mysqlCon.getRS();//判断结果集是否为空if(rs!=null){try {//将光标移动到结果集末端,注意此处不能使用rs.afterLast();否则为空值。rs.last();//获取结果集行数i=rs.getRow();//判断结果集是否存在if(i>0){//将光标移动到结果集前端rs.beforeFirst();//创建list队列list=new ArrayList();//循环遍历所有行数while(rs.next()){//创建Map容器Map<String,String> map=new HashMap<String,String >();//遍历每行元素的内容String userName=rs.getString("userName");String password=rs.getString("password");String sex=rs.getString("sex");String age=rs.getString("age");String address=rs.getString("address");//将获取的参数放到Map容器中map.put("userName", userName);map.put("password", password);map.put("sex", sex);map.put("age", age);map.put("address", address);//将Map容器添加到list队列中list.add(map);//在控制台打印出每一行的结果System.out.println("userName："+userName+"   password："+password+"   sex："+sex+"   age："+age+"   address："+address);}}else{System.out.println("结果集为空！");}} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}}else{System.out.println("结果集不存在！");}//关闭链接mysqlCon.getClose();//返回list队列return list;}}

web.xml源代码：

<?xml version="1.0" encoding="UTF-8"?><web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">  <servlet>        <servlet-name>servletAction</servlet-name>    <servlet-class>com.action.servletAction</servlet-class>  </servlet>  <servlet-mapping>    <servlet-name>servletAction</servlet-name>    <url-pattern>/servletAction</url-pattern>  </servlet-mapping>  <welcome-file-list>    <welcome-file>index.jsp</welcome-file>  </welcome-file-list></web-app>

index.jsp源代码：

<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%><%String path = request.getContextPath();String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";%><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"><html>  <head>    <base href="<%=basePath%>">        <title>My JSP 'index.jsp' starting page</title><meta http-equiv="pragma" content="no-cache"><meta http-equiv="cache-control" content="no-cache"><meta http-equiv="expires" content="0">    <meta http-equiv="keywords" content="keyword1,keyword2,keyword3"><meta http-equiv="description" content="This is my page"><!--<link rel="stylesheet" type="text/css" href="styles.css">-->  </head>    <body>     插入新的学生<br>  <form action="servletAction?action=insert" method="post">  姓名:<input type="text" name="userName">  密码:<input type="password" name="password">  性别:<select name="sex">  <option>男</option>  <option>女</option>  </select>  年龄:<input type="text" name="age" size="5">  地址:<input type="text" name="address">  <input type="submit" value="确定"><input type="reset" value="重置">  </form> 修改学生信息<br>  <form action="servletAction?action=update" method="post">  姓名:<input type="text" name="userName">  <select name="upOption">  <option>请选择</option>  <option>姓名</option>   <option>密码</option>    <option>性别</option>     <option>年龄</option>      <option>地址</option>  </select><input type="text" name="upValue" >  <input type="submit" value="确定"><input type="reset" value="重置">  </form>  删除学生信息<br>  <form action="servletAction?action=delete" method="post">  <select name="delOption">  <option>id</option>  <option>姓名</option>   <option>密码</option>    <option>性别</option>     <option>年龄</option>      <option>地址</option>  </select><input type="text" name="delValue" >  <input type="submit" value="确定"><input type="reset" value="重置">  </form>    查询学生信息<br>  <form action="servletAction?action=select" method="post">  姓名:<input type="text" name="userName">  密码:<input type="password" name="password">  性别:<select name="sex">  <option>请选择</option>  <option>男</option>  <option>女</option>  </select>  年龄:<input type="text" name="age" size="5">  地址:<input type="text" name="address">  <input type="submit" value="确定"><input type="reset" value="重置">  </form>    </body></html>

运行界面：

查询结果界面：