主要内容
案例需求介绍
业务实现
一、 案例需求
1 需求：
实现用户登录与退出登录功能，要求一个用户只能在一处登录。
完成对用户表的 CRUD 操作。
使用技术：
JSP、Servlet、Filter、Listener、JDBC、MySQL
2 创建数据库表
CREATE TABLE `users` (
`userid` int(11) NOT NULL AUTO_INCREMENT,
`username` varchar(30) DEFAULT NULL,
`userpwd` varchar(30) DEFAULT NULL,
`usersex` varchar(2) DEFAULT NULL,
`phonenumber` varchar(30) DEFAULT NULL,
`qqnumber` varchar(20) DEFAULT NULL,
PRIMARY KEY (`userid`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
3 搭建环境
3.1创建项目
3.2添加 jar 包
3.3添加 jstl 标签库的约束文件
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
3.4创建包
3.5创建 POJO
package com.bjsxt.pojo;
public class Users {
private int userid;
private String username;
private String userpwd;
private String usersex;
private String phonenumber;
private String qqnumber;
public int getUserid() {
return userid;
}
public void setUserid(int userid) {
this.userid = userid;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getUserpwd() {
return userpwd;
}
public void setUserpwd(String userpwd) {
this.userpwd = userpwd;
}
public String getUsersex() {
return usersex;
}
public void setUsersex(String usersex) {
this.usersex = usersex;
}
public String getPhonenumber() {
return phonenumber;
}
public void setPhonenumber(String phonenumber) {
this.phonenumber = phonenumber;
}
public String getQqnumber() {
return qqnumber;
}
public void setQqnumber(String qqnumber) {
this.qqnumber = qqnumber;
}
}
3.6创建 JDBC 工具类
db.properties
jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/bjsxt?useUnicode=true&characterEncoding=utf8
jdbc.username=root
jdbc.password=root
JdbcUtils
package com.bjsxt.commons;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.util.ResourceBundle;
public class JdbcUtils {
private static String driver;
private static String url;
private static String username;
private static String password;
static{
try {
ResourceBundle bundle = ResourceBundle.getBundle("db");
driver = bundle.getString("jdbc.driver");
url = bundle.getString("jdbc.url");
username = bundle.getString("jdbc.username");
password = bundle.getString("jdbc.password");
Class.forName(driver);
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
}
//获取连接方法
public static Connection getConnection(){
Connection conn = null;
try{
conn = DriverManager.getConnection(url,username,password);
}catch(Exception e){
e.printStackTrace();
}
return conn;
}
//关闭连接
public static void closeConnection(Connection conn){
try {
conn.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
二、 业务实现
1 用户登录
1.1创建登录页面
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>欢迎登录后台管理系统</title>
<link href="css/style.css" rel="stylesheet" type="text/css" />
<script language="JavaScript" src="js/jquery.js"></script>
<script src="js/cloud.js" type="text/javascript"></script>
<script language="javascript">
if(window.parent.length > 0){
window.parent.location="login.jsp";
}
$(function(){
$('.loginbox').css({
'position':'absolute','left':($(window).width()-692)/2});
$(window).resize(function(){
$('.loginbox').css({
'position':'absolute','left':($(window).width()-692)/2});
})
});
function change(){
$("#code").attr("src","validateCode.do?"+Math.random());
}
</script>
</head>
<body style="background-color:#1c77ac; background-image:url(images/light.png); background-repeat:no-repeat; background-position:center top; overflow:hidden;">
<div id="mainBody">
<div id="cloud1" class="cloud"></div>
<div id="cloud2" class="cloud"></div>
</div>
<div class="logintop">
<ul>
<li><a href="#">回首页</a></li>
<li><a href="#">帮助</a></li>
<li><a href="#">关于</a></li>
</ul>
</div>
<div class="loginbody">
${
msg}
<div class="loginbox loginbox2">
<form action="login.do" method="post">
<ul>
<li><input name="username" type="text" class="loginuser" value="admin" onclick="JavaScript:this.value=''"/></li>
<li><input name="userpwd" type="passwor" class="loginpwd" value="密码" onclick="JavaScript:this.value=''"/></li>
<li class="yzm">
<span><input name="code" type="text" value="验证码" onclick="JavaScript:this.value=''"/></span><cite><img id="code" src="validateCode.do" onclick="change()"></cite>
</li>
<li><input name="" type="submit" class="loginbtn" value="登录" onclick="javascript:window.location='main.html'" /></li>
</ul>
</form>
</div>
</div>
</body>
</html>
1.2创建登录业的务持久层
package com.bjsxt.dao;
import com.bjsxt.pojo.Users;
public interface UserLoginDao {
public Users selectUsersByUserNameAndUserPwd(String username,String userpwd);
}
package com.bjsxt.dao.impl;
import com.bjsxt.commons.JdbcUtils;
import com.bjsxt.dao.UserLoginDao;
import com.bjsxt.pojo.Users;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
public class UserLoginDaoImpl implements UserLoginDao {
/**
* 用户登录的数据库查询
* @param username
* @param userpwd
* @return
*/
@Override
public Users selectUsersByUserNameAndUserPwd(String username, String userpwd) {
Users user = null;
Connection conn = null;
try{
conn = JdbcUtils.getConnection();
PreparedStatement ps = conn.prepareStatement("select * from users where username = ? and userpwd = ?");
ps.setString(1,username);
ps.setString(2,userpwd);
ResultSet resultSet = ps.executeQuery();
while(resultSet.next()){
user = new Users();
user.setUsersex(resultSet.getString("usersex"));
user.setUserpwd(resultSet.getString("userpwd"));
user.setUsername(resultSet.getString("username"));
user.setUserid(resultSet.getInt("userid"));
user.setPhonenumber(resultSet.getString("phonenumber"));
user.setQqnumber(resultSet.getString("qqnumber"));
}
}catch(Exception e){
e.printStackTrace();
}finally{
}
return user;
}
}
1.3创建登录业务的业务层
创建自定义异常
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package com.bjsxt.exception;
/**
* 用户登录状态的自定义异常
*/
public class UserNotFoundException extends RuntimeException{
public UserNotFoundException() {
}
public UserNotFoundException(String message) {
super(message);
}
public UserNotFoundException(String message, Throwable cause) {
super(message, cause);
}
}
创建业务层
package com.bjsxt.service;
import com.bjsxt.pojo.Users;
public interface UserLoginService {
Users userLogin(String username,String userpwd);
}
package com.bjsxt.service.impl;
import com.bjsxt.dao.UserLoginDao;
import com.bjsxt.dao.impl.UserLoginDaoImpl;
import com.bjsxt.exception.UserNotFoundException;
import com.bjsxt.pojo.Users;
import com.bjsxt.service.UserLoginService;
/**
* 用户登录业务
*/
public class UserLoginServiceImpl implements UserLoginService {
/**
* 用户登录
* @param username
* @param userpwd
* @return
*/
@Override
public Users userLogin(String username, String userpwd) {
UserLoginDao userLoginDao = new UserLoginDaoImpl();
Users users = userLoginDao.selectUsersByUserNameAndUserPwd(username, userpwd);
if(users == null){
throw new UserNotFoundException("用户名或密码有误！");
}
return users;
}
}
1.4创建登录业务的 web 层
1.4.1 创建 Servlet
package com.bjsxt.web.servlet;
import com.bjsxt.commons.Constants;
import com.bjsxt.exception.UserNotFoundException;
import com.bjsxt.pojo.Users;
import com.bjsxt.service.UserLoginService;
import com.bjsxt.service.impl.UserLoginServiceImpl;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.io.IOException;
/**
* 处理用户登录请求
*/
@WebServlet("/login.do")
public class UserLoginServlet extends HttpServlet {
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
this.doPost(req, resp);
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
String username = req.getParameter("username");
String userpwd = req.getParameter("userpwd");
try{
UserLoginService userLoginService = new UserLoginServiceImpl();
Users users = userLoginService.userLogin(username, userpwd);
//建立客户端与服务端的会话状态
HttpSession session = req.getSession();
session.setAttribute(Constants.USER_SESSION_KEY,users);
//使用重定向方式跳转首页
resp.sendRedirect("main.jsp");
}catch(UserNotFoundException e){
req.setAttribute("msg",e.getMessage());
req.getRequestDispatcher("login.jsp").forward(req,resp);
}catch (Exception e){
resp.sendRedirect("error.jsp");
}
}
}
1.4.2 添加登录后的首页
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>信息管理系统界面</title>
</head>
<frameset rows="*,31" cols="*" frameborder="no" border="0" framespacing="0">
<frameset cols="187,*" frameborder="no" border="0" framespacing="0">
<frame src="left.jsp" name="leftFrame" scrolling="No" noresize="noresize" id="leftFrame" title="leftFrame" />
<frame src="index.jsp" name="rightFrame" id="rightFrame" title="rightFrame" />
</frameset>
<frame src="footer.jsp" name="bottomFrame" scrolling="No" noresize="noresize" id="bottomFrame" title="bottomFrame" />
</frameset>
<noframes><body>
</body></noframes>
</html>
</html>
1.4.3 创建登录业务的 Filter
package com.bjsxt.web.filter;
import com.bjsxt.commons.Constants;
import com.bjsxt.pojo.Users;
import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;
import java.io.IOException;
/**
* 判断当前客户端浏览器是否登录的Filter
*/
@WebFilter(urlPatterns = {
"*.do","*.jsp"})
public class UserLoginFilter implements Filter {
@Override
public void init(FilterConfig filterConfig) throws ServletException {
}
@Override
public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
HttpServletRequest request = (HttpServletRequest)servletRequest;
String uri = request.getRequestURI();
//判断当前请求的是否为login.jsp或者login.do，如果请求的是用户登录的资源那么需要放行。
if(uri.indexOf("login.jsp") != -1 || uri.indexOf("login.do") != -1|| uri.indexOf("validateCode.do") != -1){
filterChain.doFilter(servletRequest, servletResponse);
}else{
HttpSession session = request.getSession();
Users users = (Users) session.getAttribute(Constants.USER_SESSION_KEY);
if(users != null){
filterChain.doFilter(servletRequest, servletResponse);
}else{
request.setAttribute(Constants.REQUEST_MSG,"不登录不好使！");
request.getRequestDispatcher("login.jsp").forward(servletRequest, servletResponse);
}
}
}
@Override
public void destroy() {
}
}
1.5用户只能在一处登录
1.5.1 修改处理登录请求的 Servlet
package com.bjsxt.web.servlet;
import com.bjsxt.commons.Constants;
import com.bjsxt.exception.UserNotFoundException;
import com.bjsxt.pojo.Users;
import com.bjsxt.service.UserLoginService;
import com.bjsxt.service.impl.UserLoginServiceImpl;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.io.IOException;
/**
* 处理用户登录请求
*/
@WebServlet("/login.do")
public class UserLoginServlet extends HttpServlet {
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
this.doPost(req, resp);
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
String username = req.getParameter("username");
String userpwd = req.getParameter("userpwd");
try{
UserLoginService userLoginService = new UserLoginServiceImpl();
Users users = userLoginService.userLogin(username, userpwd);
//建立客户端与服务端的会话状态
HttpSession session = req.getSession();
session.setAttribute(Constants.USER_SESSION_KEY,users);
ServletContext servletContext = this.getServletContext();
HttpSession temp = (HttpSession) servletContext.getAttribute(users.getUserid()+"");
if(temp != null){
servletContext.removeAttribute(users.getUserid()+"");
temp.invalidate();
}
servletContext.setAttribute(users.getUserid()+"",session);
//使用重定向方式跳转首页
resp.sendRedirect("main.jsp");
}catch(UserNotFoundException e){
req.setAttribute("msg",e.getMessage());
req.getRequestDispatcher("login.jsp").forward(req,resp);
}catch (Exception e){
resp.sendRedirect("error.jsp");
}
}
}
1.5.2 修改登录页面
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>欢迎登录后台管理系统</title>
<link href="css/style.css" rel="stylesheet" type="text/css" />
<script language="JavaScript" src="js/jquery.js"></script>
<script src="js/cloud.js" type="text/javascript"></script>
<script language="javascript">
if(window.parent.length > 0){
window.parent.location="login.jsp";
}
$(function(){
$('.loginbox').css({
'position':'absolute','left':($(window).width()-692)/2});
$(window).resize(function(){
$('.loginbox').css({
'position':'absolute','left':($(window).width()-692)/2});
})
});
function change(){
$("#code").attr("src","validateCode.do?"+Math.random());
}
</script>
</head>
<body style="background-color:#1c77ac; background-image:url(images/light.png); background-repeat:no-repeat; background-position:center top; overflow:hidden;">
<div id="mainBody">
<div id="cloud1" class="cloud"></div>
<div id="cloud2" class="cloud"></div>
</div>
<div class="logintop">
<ul>
<li><a href="#">回首页</a></li>
<li><a href="#">帮助</a></li>
<li><a href="#">关于</a></li>
</ul>
</div>
<div class="loginbody">
${
msg}
<div class="loginbox loginbox2">
<form action="login.do" method="post">
<ul>
<li><input name="username" type="text" class="loginuser" value="admin" onclick="JavaScript:this.value=''"/></li>
<li><input name="userpwd" type="passwor" class="loginpwd" value="密码" onclick="JavaScript:this.value=''"/></li>
<li class="yzm">
<span><input name="" type="text" value="验证码" onclick="JavaScript:this.value=''"/></span><cite>X3D5S</cite>
</li>
<li><input name="" type="submit" class="loginbtn" value="登录" onclick="javascript:window.location='main.html'" /></li>
</ul>
</form>
</div>
</div>
</body>
</html>
1.5.3 解决 HttpSession 超时销毁时的异常问题
package com.bjsxt.web.listener;
import com.bjsxt.commons.Constants;
import com.bjsxt.pojo.Users;
import javax.servlet.ServletContext;
import javax.servlet.annotation.WebListener;
import javax.servlet.http.HttpSession;
import javax.servlet.http.HttpSessionEvent;
import javax.servlet.http.HttpSessionListener;
/**
* 解决HttpSession被反复销毁的问题
*/
@WebListener
public class HttpSessionLifecycleListener implements HttpSessionListener {
@Override
public void sessionCreated(HttpSessionEvent se) {
}
@Override
public void sessionDestroyed(HttpSessionEvent se) {
//获取ServletContext对象，然后将所对应的HttpSession删除掉
HttpSession session = se.getSession();
ServletContext servletContext = session.getServletContext();
Users users = (Users) session.getAttribute(Constants.USER_SESSION_KEY);
servletContext.removeAttribute(users.getUserid()+"");
}
}
1.6在登录中添加验证码功能
添加产生验证的 Servlet
package com.bjsxt.commons;
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.util.Random;
import javax.imageio.ImageIO;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
@WebServlet("/validateCode.do")
public class ValidateCodeServlet extends HttpServlet {
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
// 在内存中创建图象
int width = 70, height = 45;
BufferedImage image = new BufferedImage(width, height,
BufferedImage.TYPE_INT_RGB);
// 获取图形上下文
Graphics g = image.getGraphics();
// 生成随机类
Random random = new Random();
// 设定背景色
g.setColor(getRandColor(200, 250));
g.fillRect(0, 0, width, height);
// 设定字体
g.setFont(new Font("Times New Roman", Font.PLAIN, 20));
// 随机产生155条干扰线，使图象中的认证码不易被其它程序探测到
g.setColor(getRandColor(160, 200));
for (int i = 0; i < 155; i++) {
int x = random.nextInt(width);
int y = random.nextInt(height);
int xl = random.nextInt(12);
int yl = random.nextInt(12);
g.drawLine(x, y, x + xl, y + yl);
}
// 取随机产生的认证码(4位数字)
String sRand = "";
for (int i = 0; i < 4; i++) {
String rand = String.valueOf(random.nextInt(10));
sRand += rand;
// 将认证码显示到图象中
g.setColor(new Color(20 + random.nextInt(110), 20 + random
.nextInt(110), 20 + random.nextInt(110)));
// 调用函数出来的颜色相同，可能是因为种子太接近，所以只能直接生成
g.drawString(rand, 13 * i + 6, 16);
}
// 图象生效
g.dispose();
try {
ImageIO.write(image, "JPEG", response.getOutputStream());
} catch (Exception e) {
System.out.println("验证码图片产生出现错误：" + e.toString());
}
//保存验证码到Session
request.getSession().setAttribute(Constants.VALIDATE_CODE_KEY, sRand);
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
this.doGet(request, response);
}
/*
* 给定范围获得随机颜色
*/
private Color getRandColor(int fc, int bc) {
Random random = new Random();
if (fc > 255)
fc = 255;
if (bc > 255)
bc = 255;
int r = fc + random.nextInt(bc - fc);
int g = fc + random.nextInt(bc - fc);
int b = fc + random.nextInt(bc - fc);
return new Color(r, g, b);
}
}
修改登录页面
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>欢迎登录后台管理系统</title>
<link href="css/style.css" rel="stylesheet" type="text/css" />
<script language="JavaScript" src="js/jquery.js"></script>
<script src="js/cloud.js" type="text/javascript"></script>
<script language="javascript">
if(window.parent.length > 0){
window.parent.location="login.jsp";
}
$(function(){
$('.loginbox').css({
'position':'absolute','left':($(window).width()-692)/2});
$(window).resize(function(){
$('.loginbox').css({
'position':'absolute','left':($(window).width()-692)/2});
})
});
function change(){
$("#code").attr("src","validateCode.do?"+Math.random());
}
</script>
</head>
<body style="background-color:#1c77ac; background-image:url(images/light.png); background-repeat:no-repeat; background-position:center top; overflow:hidden;">
<div id="mainBody">
<div id="cloud1" class="cloud"></div>
<div id="cloud2" class="cloud"></div>
</div>
<div class="logintop">
<ul>
<li><a href="#">回首页</a></li>
<li><a href="#">帮助</a></li>
<li><a href="#">关于</a></li>
</ul>
</div>
<div class="loginbody">
${
msg}
<div class="loginbox loginbox2">
<form action="login.do" method="post">
<ul>
<li><input name="username" type="text" class="loginuser" value="admin" onclick="JavaScript:this.value=''"/></li>
<li><input name="userpwd" type="passwor" class="loginpwd" value="密码" onclick="JavaScript:this.value=''"/></li>
<li class="yzm">
<span><input name="code" type="text" value="验证码" onclick="JavaScript:this.value=''"/></span><cite><img id="code" src="validateCode.do" onclick="change()"></cite>
</li>
<li><input name="" type="submit" class="loginbtn" value="登录" onclick="javascript:window.location='main.html'" /></li>
</ul>
</form>
</div>
</div>
</body>
</html>
修改用户登录过滤器
package com.bjsxt.web.filter;
import com.bjsxt.commons.Constants;
import com.bjsxt.pojo.Users;
import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;
import java.io.IOException;
/**
* 判断当前客户端浏览器是否登录的Filter
*/
@WebFilter(urlPatterns = {
"*.do","*.jsp"})
public class UserLoginFilter implements Filter {
@Override
public void init(FilterConfig filterConfig) throws ServletException {
}
@Override
public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
HttpServletRequest request = (HttpServletRequest)servletRequest;
String uri = request.getRequestURI();
//判断当前请求的是否为login.jsp或者login.do，如果请求的是用户登录的资源那么需要放行。
if(uri.indexOf("login.jsp") != -1 || uri.indexOf("login.do") != -1|| uri.indexOf("validateCode.do") != -1){
filterChain.doFilter(servletRequest, servletResponse);
}else{
HttpSession session = request.getSession();
Users users = (Users) session.getAttribute(Constants.USER_SESSION_KEY);
if(users != null){
filterChain.doFilter(servletRequest, servletResponse);
}else{
request.setAttribute(Constants.REQUEST_MSG,"不登录不好使！");
request.getRequestDispatcher("login.jsp").forward(servletRequest, servletResponse);
}
}
}
@Override
public void destroy() {
}
}
修改处理登录请求的 Servlet
package com.bjsxt.web.servlet;
import com.bjsxt.commons.Constants;
import com.bjsxt.exception.UserNotFoundException;
import com.bjsxt.pojo.Users;
import com.bjsxt.service.UserLoginService;
import com.bjsxt.service.impl.UserLoginServiceImpl;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.io.IOException;
/**
* 处理用户登录请求
*/
@WebServlet("/login.do")
public class UserLoginServlet extends HttpServlet {
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
this.doPost(req, resp);
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
String username = req.getParameter("username");
String userpwd = req.getParameter("userpwd");
String code = req.getParameter("code");
try{
HttpSession session = req.getSession();
String codeTemp = (String)session.getAttribute(Constants.VALIDATE_CODE_KEY);
if(codeTemp.equals(code)){
UserLoginService userLoginService = new UserLoginServiceImpl();
Users users = userLoginService.userLogin(username, userpwd);
//建立客户端与服务端的会话状态
session.setAttribute(Constants.USER_SESSION_KEY,users);
ServletContext servletContext = this.getServletContext();
HttpSession temp = (HttpSession) servletContext.getAttribute(users.getUserid()+"");
if(temp != null){
servletContext.removeAttribute(users.getUserid()+"");
temp.invalidate();
}
servletContext.setAttribute(users.getUserid()+"",session);
//使用重定向方式跳转首页
resp.sendRedirect("main.jsp");
}else{
req.setAttribute(Constants.REQUEST_MSG,"验证码有误，请重新输入");
req.getRequestDispatcher("login.jsp").forward(req,resp);
}
}catch(UserNotFoundException e){
req.setAttribute("msg",e.getMessage());
req.getRequestDispatcher("login.jsp").forward(req,resp);
}catch (Exception e){
e.printStackTrace();
resp.sendRedirect("error.jsp");
}
}
}
2 用户退出登录
修改 left.jsp 页面
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
<link href="css/style.css" rel="stylesheet" type="text/css" />
<script language="JavaScript" src="js/jquery.js"></script>
<script type="text/javascript">
$(function(){
//导航切换
$(".menuson .header").click(function(){
var $parent = $(this).parent();
$(".menuson>li.active").not($parent).removeClass("active open").find('.sub-menus').hide();
$parent.addClass("active");
if(!!$(this).next('.sub-menus').size()){
if($parent.hasClass("open")){
$parent.removeClass("open").find('.sub-menus').hide();
}else{
$parent.addClass("open").find('.sub-menus').show();
}
}
});
// 三级菜单点击
$('.sub-menus li').click(function(e) {
$(".sub-menus li.active").removeClass("active")
$(this).addClass("active");
});
$('.title').click(function(){
var $ul = $(this).next('ul');
$('dd').find('.menuson').slideUp();
if($ul.is(':visible')){
$(this).next('.menuson').slideUp();
}else{
$(this).next('.menuson').slideDown();
}
});
})
</script>
</head>
<body style="background:#f0f9fd;">
<div class="lefttop"><span></span>导航菜单</div>
<dl class="leftmenu">
<dd>
<div class="title"><span><img src="images/leftico03.png" /></span>用户管理</div>
<ul class="menuson">
<li><cite></cite><a href="usermanager/addUser.jsp" target="rightFrame">添加用户</a><i></i></li>
<li><cite></cite><a href="usermanager/findUser.jsp" target="rightFrame">查询用户</a><i></i></li>
<li><cite></cite><a href="logout.do" target="rightFrame">退出登录</a><i></i></li>
</ul>
</dd>
</dl>
</body>
</html>
创建 Servlet
package com.bjsxt.web.servlet;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.io.IOException;
/**
* 用户退出登录
*/
@WebServlet("/logout.do")
public class LogoutServlet extends HttpServlet {
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
this.doPost(req, resp);
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
HttpSession session = req.getSession();
session.invalidate();
resp.sendRedirect("login.jsp");
}
}
3 添加用户业务
3.1创建添加用户持久层
package com.bjsxt.dao;
import com.bjsxt.pojo.Users;
public interface UserManagerDao {
void insertUser(Users users);
}
package com.bjsxt.dao.impl;
import com.bjsxt.commons.JdbcUtils;
import com.bjsxt.dao.UserManagerDao;
import com.bjsxt.pojo.Users;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.util.ArrayList;
import java.util.List;
/**
* 用户管理持久层
*/
public class UserManagerDaoImpl implements UserManagerDao {
@Override
public void insertUser(Users users) {
Connection conn = null;
try{
conn = JdbcUtils.getConnection();
conn.setAutoCommit(false);
PreparedStatement ps = conn.prepareStatement("insert into users values(default,?,?,?,?,?)");
ps.setString(1,users.getUsername());
ps.setString(2,users.getUserpwd());
ps.setString(3,users.getUsersex());
ps.setString(4,users.getPhonenumber());
ps.setString(5,users.getQqnumber());
ps.execute();
conn.commit();
}catch(Exception e){
e.printStackTrace();
JdbcUtils.rollbackConnection(conn);
}finally{
JdbcUtils.closeConnection(conn);
}
}
}
3.2创建添加用户业务层
public interface UserManagerService {
void addUser(Users users);
}
package com.bjsxt.service.impl;
import com.bjsxt.dao.UserManagerDao;
import com.bjsxt.dao.impl.UserManagerDaoImpl;
import com.bjsxt.pojo.Users;
import com.bjsxt.service.UserManagerService;
import java.util.List;
/**
* 用户管理业务层
*/
public class UserManagerServiceImpl implements UserManagerService {
/**
* 添加用户
* @param users
*/
@Override
public void addUser(Users users) {
UserManagerDao userManagerDao = new UserManagerDaoImpl();
userManagerDao.insertUser(users);
}
}
3.3创建添加用户的 Servlet
/**
* 处理用管理请求
*/
@WebServlet("/userManager.do")
public class UserManagerServlet extends HttpServlet {
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
this.doPost(req, resp);
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
String flag = req.getParameter("flag");
if("addUser".equals(flag)){
this.addUser(req,resp);
}
}
//处理添加用户请求
private void addUser(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
Users users = this.createUsers(req);
try{
UserManagerService userManagerService = new UserManagerServiceImpl();
userManagerService.addUser(users);
resp.sendRedirect("ok.jsp");
}catch(Exception e){
e.printStackTrace();
resp.sendRedirect("error.jsp");
}
}
//获取用户提交数据
private Users createUsers(HttpServletRequest req){
String username = req.getParameter("username");
String userpwd = req.getParameter("userpwd");
String usersex = req.getParameter("usersex");
String phonenumber = req.getParameter("phonenumber");
String qqnumber = req.getParameter("qqnumber");
Users users = new Users();
users.setQqnumber(qqnumber);
users.setPhonenumber(phonenumber);
users.setUsername(username);
users.setUserpwd(userpwd);
users.setUsersex(usersex);
return users;
}
}
3.4创建添加用户页面
创建添加用户页面
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
<link href="../css/style.css" rel="stylesheet" type="text/css" />
<link href="../css/style.css" rel="stylesheet" type="text/css" />
<link href="../css/select.css" rel="stylesheet" type="text/css" />
</head>
<body>
<div class="place">
<span>位置：</span>
<ul class="placeul">
<li><a href="#">用户管理</a></li>
<li><a href="#">添加用户</a></li>
</ul>
</div>
<div class="formbody">
<div class="formtitle"><span>基本信息</span></div>
<form action="../userManager.do" method="post">
<input type="hidden" name="flag" value="addUser"/>
<ul class="forminfo">
<li>
<label>用户名</label>
<input name="username" type="text" class="dfinput" /></li>
<li>
<li>
<label>用户密码</label>
<input name="userpwd" type="text" class="dfinput" /><i></i></li>
<li>
<label>性别</label><cite>
<input name="usersex" type="radio" value="1" checked="checked" />男
<input name="usersex" type="radio" value="0" />女
</li>
<li>
<label>联系方式</label>
<input name="phonenumber" type="text" class="dfinput" />
</li>
<li>
<label>QQ号</label>
<input name="qqnumber" type="text" class="dfinput" />
</li>
<li>
<label> </label>
<input type="submit" class="btn" value="确认保存" />
</li>
</ul>
</form>
</div>
</body>
</html>
创建成功页面
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title></title>
<link href="css/style.css" rel="stylesheet" type="text/css" />
<script type="text/javascript">
function submitForm(){
window.close();
}
</script>
</head>
<body>
<div class="place">
<span>位置：</span>
<ul class="placeul">
<li><a href="#">操作提示</a></li>
</ul>
</div>
操作成功!
</body>
</html>
4 查询用户业务
4.1创建查询用户持久层
List<Users> selectUserByProperty(Users users);
/**
* 查询用户
* @param users
* @return
*/
@Override
public List<Users> selectUsersByProperty(Users users) {
Connection conn = null;
List<Users> list = new ArrayList<>();
try{
conn = JdbcUtils.getConnection();
String sql = this.createSQL(users);
PreparedStatement preparedStatement = conn.prepareStatement(sql);
ResultSet resultSet = preparedStatement.executeQuery();
while(resultSet.next()){
Users user = new Users();
user.setUserid(resultSet.getInt("userid"));
user.setPhonenumber(resultSet.getString("phonenumber"));
user.setQqnumber(resultSet.getString("qqnumber"));
user.setUserpwd(resultSet.getString("userpwd"));
user.setUsername(resultSet.getString("username"));
user.setUsersex(resultSet.getString("usersex"));
list.add(user);
}
}catch(Exception e){
e.printStackTrace();
}finally{
JdbcUtils.closeConnection(conn);
}
return list;
}
//拼接查询的SQL语句
private String createSQL(Users users){
StringBuffer stringBuffer = new StringBuffer("select * from users where 1=1 ");
if(users.getUsersex() != null && users.getUsersex().length() > 0){
stringBuffer.append(" and usersex = "+users.getUsersex());
}
if(users.getQqnumber() != null && users.getQqnumber().length() > 0){
stringBuffer.append(" and qqnumber = "+users.getQqnumber());
}
if(users.getUsername() != null && users.getUsername().length() > 0){
stringBuffer.append(" and username = "+users.getUsername());
}
if(users.getPhonenumber() != null &&users.getPhonenumber().length() > 0){
stringBuffer.append(" and phonenumber = "+users.getPhonenumber());
}
return stringBuffer.toString();
}
4.2创建查询用户业务层
List<Users> findUser(Users users);
/**
* 查询用户
* @param users
* @return
*/
@Override
public List<Users> findUser(Users users) {
UserManagerDao userManagerDao = new UserManagerDaoImpl();
return userManagerDao.selectUsersByProperty(users);
}
4.3创建查询用户的 Servlet
/**
* 处理查询用户请求
*/
private void findUser(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException{
Users user = this.createUsers(req);
try{
UserManagerService userManagerService = new UserManagerServiceImpl();
List<Users> list = userManagerService.findUser(user);
req.setAttribute("list",list);
req.getRequestDispatcher("usermanager/viewUser.jsp").forward(req,resp);
}catch(Exception e){
e.printStackTrace();
resp.sendRedirect("error.jsp");
}
}
4.4创建查询用户与显示结果的页面
创建 findUser.jsp 页面
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
<link href="../css/style.css" rel="stylesheet" type="text/css" />
<link href="../css/select.css" rel="stylesheet" type="text/css" />
</head>
<body>
<div class="place">
<span>位置：</span>
<ul class="placeul">
<li><a href="#">用户管理</a></li>
<li><a href="#">查询用户</a></li>
</ul>
</div>
<div class="rightinfo">
<form action="../userManager.do" method="post">
<input type="hidden" name="flag" value="findUser"/>
<ul class="prosearch">
<li>
<label>查询：</label>
<i>用户名</i>
<a>
<input name="username" type="text" class="scinput" />
</a>
</li>
<li>
<label>性别：</label>
<input name="usersex" type="radio" value="1" checked="checked" /> 男
<input name="usersex" type="radio" value="0" /> 女
</li>
<li>
<label>手机号：</label>
<a>
<input name="phonenumber" type="text" class="scinput" />
</a>
</li>
<li>
<label>QQ号：</label>
<a>
<input name="qqnumber" type="text" class="scinput" />
</a>
</li>
<a>
<input type="submit" class="sure" value="查询"/>
</a>
</ul>
</form>
</body>
</html>
创建 viewUser.jsp 页面
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
<link href="css/style.css" rel="stylesheet" type="text/css" />
</head>
<body>
<div class="place">
<span>位置：</span>
<ul class="placeul">
<li><a href="#">用户管理</a></li>
<li><a href="#">查询用户</a></li>
<li><a href="#">查询结果</a></li>
</ul>
</div>
<div class="rightinfo">
<div class="formtitle1"><span>用户列表</span></div>
<table class="tablelist" >
<thead>
<tr>
<th>序号</th>
<th>用户名</th>
<th>用户性别</th>
<th>手机号</th>
<th>QQ号</th>
<th>操作</th>
</tr>
</thead>
<tbody>
<c:forEach items="${list}" var="user" varStatus="status">
<tr>
<td>${
status.count}</td>
<td>${
user.username}</td>
<td>
<c:choose>
<c:when test="${user.usersex == 1}">
男
</c:when>
<c:otherwise>
女
</c:otherwise>
</c:choose>
</td>
<td>${
user.phonenumber}</td>
<td>${
user.qqnumber}</td>
<td><a href="userManager.do?flag=preUpdate&userid=${user.userid}" class="tablelink">修改</a> <a href="userManager.do?userid=${user.userid}" class="tablelink click"> 删除</a></td>
</tr>
</c:forEach>
</tbody>
</table>
<div class="tip">
<div class="tiptop"><span>提示信息</span><a></a></div>
<div class="tipinfo">
<span><img src="images/ticon.png" /></span>
<div class="tipright">
<p>是否确认对信息的修改 ？</p>
<cite>如果是请点击确定按钮 ，否则请点取消。</cite>
</div>
</div>
<div class="tipbtn">
<input name="" type="button" class="sure" value="确定" />
<input name="" type="button" class="cancel" value="取消" />
</div>
</div>
</div>
</body>
</html>
5 更新用户业务
5.1预更新用户的查询
5.1.1 创建预更新用户查询持久层
Users selectUserByUserId(int userid);
/**
* 根据用户ID查询用户
* @param userid
* @return
*/
@Override
public Users selectUserByUserId(int userid) {
Connection conn = null;
Users user = null;
try{
conn = JdbcUtils.getConnection();
PreparedStatement preparedStatement = conn.prepareStatement("select * from users where userid = ?");
preparedStatement.setInt(1,userid);
ResultSet resultSet = preparedStatement.executeQuery();
while(resultSet.next()){
user = new Users();
user.setUserid(resultSet.getInt("userid"));
user.setPhonenumber(resultSet.getString("phonenumber"));
user.setQqnumber(resultSet.getString("qqnumber"));
user.setUserpwd(resultSet.getString("userpwd"));
user.setUsername(resultSet.getString("username"));
user.setUsersex(resultSet.getString("usersex"));
}
}catch(Exception e){
e.printStackTrace();
}finally{
JdbcUtils.closeConnection(conn);
}
return user;
}
5.1.2 创建预更新用户业务层
Users findUserByUserId(int userid);
/**
* 预更新用户的查询
* @param userid
* @return
*/
@Override
public Users findUserByUserId(int userid) {
UserManagerDao userManagerDao = new UserManagerDaoImpl();
return userManagerDao.selectUserByUserId(userid);
}
5.1.3 创建预更新用户的 Servlet
/**
* 预更新查询
*/
private void preUpdate(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException{
String userid = req.getParameter("userid");
try{
UserManagerService userManagerService = new UserManagerServiceImpl();
Users user = userManagerService.findUserByUserId(Integer.parseInt(userid));
req.setAttribute("user",user);
req.getRequestDispatcher("usermanager/updateUser.jsp").forward(req,resp);
}catch(Exception e){
e.printStackTrace();
resp.sendRedirect("error.jsp");
}
}
5.1.4 创建更新用户页面
修改 viewUser.jsp
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
<link href="css/style.css" rel="stylesheet" type="text/css" />
</head>
<body>
<div class="place">
<span>位置：</span>
<ul class="placeul">
<li><a href="#">用户管理</a></li>
<li><a href="#">查询用户</a></li>
<li><a href="#">查询结果</a></li>
</ul>
</div>
<div class="rightinfo">
<div class="formtitle1"><span>用户列表</span></div>
<table class="tablelist" >
<thead>
<tr>
<th>序号</th>
<th>用户名</th>
<th>用户性别</th>
<th>手机号</th>
<th>QQ号</th>
<th>操作</th>
</tr>
</thead>
<tbody>
<c:forEach items="${list}" var="user" varStatus="status">
<tr>
<td>${
status.count}</td>
<td>${
user.username}</td>
<td>
<c:choose>
<c:when test="${user.usersex == 1}">
男
</c:when>
<c:otherwise>
女
</c:otherwise>
</c:choose>
</td>
<td>${
user.phonenumber}</td>
<td>${
user.qqnumber}</td>
<td><a href="userManager.do?flag=preUpdate&userid=${user.userid}" class="tablelink">修改</a> <a href="userManager.do?userid=${user.userid}" class="tablelink click"> 删除</a></td>
</tr>
</c:forEach>
</tbody>
</table>
<div class="tip">
<div class="tiptop"><span>提示信息</span><a></a></div>
<div class="tipinfo">
<span><img src="images/ticon.png" /></span>
<div class="tipright">
<p>是否确认对信息的修改 ？</p>
<cite>如果是请点击确定按钮 ，否则请点取消。</cite>
</div>
</div>
<div class="tipbtn">
<input name="" type="button" class="sure" value="确定" />
<input name="" type="button" class="cancel" value="取消" />
</div>
</div>
</div>
</body>
</html>
创建 updateUser.jsp
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
<link href="css/style.css" rel="stylesheet" type="text/css" />
</head>
<body>
<div class="place">
<span>位置：</span>
<ul class="placeul">
<li><a href="#">用户管理</a></li>
<li><a href="#">修改用户</a></li>
</ul>
</div>
<div class="formbody">
<div class="formtitle"><span>基本信息</span></div>
<form action="../userManager.do" method="post">
<ul class="forminfo">
<li><label>用户名</label><input name="username" type="text" class="dfinput" value="${user.username}"/> </li>
<li>
<label>性别</label><cite>
<c:choose>
<c:when test="${user.usersex == 1}">
<input name="usersex" type="radio" value="1" checked="checked" />男
<input name="usersex" type="radio" value="0" />女
</c:when>
<c:otherwise>
<input name="usersex" type="radio" value="1" />男
<input name="usersex" type="radio" value="0" checked="checked" />女
</c:otherwise>
</c:choose>
</li>
<li><label>手机号</label><input name="phonenumber" type="text" class="dfinput" value="${user.phonenumber}"/></li>
<li><label>QQ号</label><input name="qqnumber" type="text" class="dfinput" value="${user.qqnumber}"/></li>
<li><label> </label><input type="submit" class="btn" value="确认保存"/></li>
</ul>
</form>
</div>
</body>
</html>
5.2更新用户操作
5.2.1 创建更新用户持久层
void updateUserByUserId(Users users);
/**
* 更新用户
* @param users
*/
@Override
public void updateUserByUserId(Users users) {
Connection conn = null;
try{
conn = JdbcUtils.getConnection();
conn.setAutoCommit(false);
PreparedStatement preparedStatement = conn.prepareStatement("update users set username=? ,usersex = ?,phonenumber=?,qqnumber = ? where userid = ? ");
preparedStatement.setString(1,users.getUsername());
preparedStatement.setString(2,users.getUsersex());
preparedStatement.setString(3,users.getPhonenumber());
preparedStatement.setString(4,users.getQqnumber());
preparedStatement.setInt(5,users.getUserid());
preparedStatement.execute();
conn.commit();
}catch(Exception e){
e.printStackTrace();
JdbcUtils.rollbackConnection(conn);
}finally {
JdbcUtils.closeConnection(conn);
}
}
5.2.2 创建更新用户业务层
void modifyUser(Users users);
/**
* 修改用户
* @param users
*/
@Override
public void modifyUser(Users users) {
UserManagerDao userManagerDao = new UserManagerDaoImpl();
userManagerDao.updateUserByUserId(users);
}
5.2.3 创建更新用户 Servlet
/**
* 处理更新用户请求
*/
private void modifyUser(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException{
String userid = req.getParameter("userid");
Users users = this.createUsers(req);
users.setUserid(Integer.parseInt(userid));
try{
UserManagerService userManagerService = new UserManagerServiceImpl();
userManagerService.modifyUser(users);
resp.sendRedirect("ok.jsp");
}catch(Exception e){
e.printStackTrace();
resp.sendRedirect("error.jsp");
}
}
5.2.4 修改更新用户页面
修改 updateUser.jsp
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
<link href="css/style.css" rel="stylesheet" type="text/css" />
</head>
<body>
<div class="place">
<span>位置：</span>
<ul class="placeul">
<li><a href="#">用户管理</a></li>
<li><a href="#">修改用户</a></li>
</ul>
</div>
<div class="formbody">
<div class="formtitle"><span>基本信息</span></div>
<form action="userManager.do" method="post">
<input type="hidden" name="flag" value="modifyUser"/>
<input type="hidden" name="userid" value="${user.userid}"/>
<ul class="forminfo">
<li><label>用户名</label><input name="username" type="text" class="dfinput" value="${user.username}"/> </li>
<li>
<label>性别</label><cite>
<c:choose>
<c:when test="${user.usersex == 1}">
<input name="usersex" type="radio" value="1" checked="checked" />男
<input name="usersex" type="radio" value="0" />女
</c:when>
<c:otherwise>
<input name="usersex" type="radio" value="1" />男
<input name="usersex" type="radio" value="0" checked="checked" />女
</c:otherwise>
</c:choose>
</li>
<li><label>手机号</label><input name="phonenumber" type="text" class="dfinput" value="${user.phonenumber}"/></li>
<li><label>QQ号</label><input name="qqnumber" type="text" class="dfinput" value="${user.qqnumber}"/></li>
<li><label> </label><input type="submit" class="btn" value="确认保存"/></li>
</ul>
</form>
</div>
</body>
</html>
修改更新用户的 servlet 中的方法
/**
* 处理更新用户请求
*/
private void modifyUser(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException{
String userid = req.getParameter("userid");
Users users = this.createUsers(req);
users.setUserid(Integer.parseInt(userid));
try{
UserManagerService userManagerService = new UserManagerServiceImpl();
userManagerService.modifyUser(users);
resp.sendRedirect("ok.jsp");
}catch(Exception e){
e.printStackTrace();
resp.sendRedirect("error.jsp");
}
}
6 删除用户业务
6.1创建删除用户持久层
void deleteUserByUserId(int userid);
/**
* 根据用户ID删除用户
* @param userid
*/
@Override
public void deleteUserByUserId(int userid) {
Connection conn = null;
try{
conn = JdbcUtils.getConnection();
conn.setAutoCommit(false);
PreparedStatement ps = conn.prepareStatement("delete from users where userid = ?");
ps.setInt(1,userid);
ps.execute();
conn.commit();
}catch(Exception e){
e.printStackTrace();
JdbcUtils.rollbackConnection(conn);
}finally{
JdbcUtils.closeConnection(conn);
}
}
6.2创建删除用户业务层
void dropUser(int userid);
/**
* 删除用户
* @param userid
*/
@Override
public void dropUser(int userid) {
UserManagerDao userManagerDao = new UserManagerDaoImpl();
userManagerDao.deleteUserByUserId(userid);
}
6.3创建删除用户 Servlet
/**
* 处理删除用户的请求
*/
private void dropUser(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException{
String userid = req.getParameter("userid");
try{
UserManagerService userManagerService = new UserManagerServiceImpl();
userManagerService.dropUser(Integer.parseInt(userid));
resp.sendRedirect("ok.jsp");
}catch(Exception e){
e.printStackTrace();
resp.sendRedirect("error.jsp");
}
}
6.4修改 viewUser.jsp 页面完成用户删除
<%--
Created by IntelliJ IDEA.
User: Administrator
Date: 2020/6/2 0002
Time: 19:04
To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
<link href="css/style.css" rel="stylesheet" type="text/css" />
</head>
<body>
<div class="place">
<span>位置：</span>
<ul class="placeul">
<li><a href="#">用户管理</a></li>
<li><a href="#">查询用户</a></li>
<li><a href="#">查询结果</a></li>
</ul>
</div>
<div class="rightinfo">
<div class="formtitle1"><span>用户列表</span></div>
<table class="tablelist" >
<thead>
<tr>
<th>序号</th>
<th>用户名</th>
<th>用户性别</th>
<th>手机号</th>
<th>QQ号</th>
<th>操作</th>
</tr>
</thead>
<tbody>
<c:forEach items="${list}" var="user" varStatus="status">
<tr>
<td>${
status.count}</td>
<td>${
user.username}</td>
<td>
<c:choose>
<c:when test="${user.usersex == 1}">
男
</c:when>
<c:otherwise>
女
</c:otherwise>
</c:choose>
</td>
<td>${
user.phonenumber}</td>
<td>${
user.qqnumber}</td>
<td><a href="userManager.do?flag=preUpdate&userid=${user.userid}" class="tablelink">修改</a> <a href="userManager.do?userid=${user.userid}" class="tablelink click"> 删除</a></td>
</tr>
</c:forEach>
</tbody>
</table>
<div class="tip">
<div class="tiptop"><span>提示信息</span><a></a></div>
<div class="tipinfo">
<span><img src="images/ticon.png" /></span>
<div class="tipright">
<p>是否确认对信息的修改 ？</p>
<cite>如果是请点击确定按钮 ，否则请点取消。</cite>
</div>
</div>
<div class="tipbtn">
<input name="" type="button" class="sure" value="确定" />
<input name="" type="button" class="cancel" value="取消" />
</div>
</div>
</div>
</body>
</html>
项目练习源码：https://gitee.com/cutelili/web-combat-case-user-login
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