JavaWeb投票系统
目的
帮她完成JavaWeb课程设计，也做为练手的小项目；
功能
1、可以实现在个人登陆，在线投票，票数统计的功能；
2、规定每个投票者每天只能投一票，并要求登录成功后才可以投票；
####分块
1、Login类：实现登录
2、Vote类：实现投票
3、Vote_Filter类：过滤器类，控制登录和刷票
4、UserService类：Service类用来调用UserDao操作数据库
5、UserDao类：操作数据库类
6、Voter类：投票者模型类
7、User类： 被投者模型类
8、DBUtils类：Jdbc连接MySQL工具类
数据库（表）
投票者信息表
| 字段 | 数据类型 | 说明 |
|---|---|---|
| id | int | 序号，主键 |
| username | varchar | 用户名 |
| password | varchar | 密码 |
| record | varchar | 最后一天投票时间 |
被投者信息表
| 字段 | 数据类型 | 说明 |
|---|---|---|
| id | int | 序号，主键 |
| name | varchar | 用户名 |
| count | int | 票数 |
Login类
package cn.sy.servlet;
import java.io.IOException;
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 cn.sy.domain.Voter;
import cn.sy.service.UserService;
@WebServlet(name = "LoginServlet", urlPatterns = { "/login" })
public class Login extends HttpServlet {
@Override
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
// 1、得到登录名和密码
String username = request.getParameter("username");// 得到用户输入的登录名
String password = request.getParameter("password");// 得到用户输入的密码
// 2、将信息封装
Voter voter = new Voter();
voter.setUsername(username);
voter.setPassword(password);
UserService service = new UserService();
try {
Voter existVoter = service.login(voter);// 3、调用service中登录方法
if (existVoter == null) {// 代表用户名或密码错误，存储错误信息在request域中，请求转发到login.jsp
request.setAttribute("message", "登录失败：用户名或密码错误！");
// 登录失败，请求转发到登录页面显示错误信息message
request.getRequestDispatcher("/login.jsp").forward(request,
response);
return;
} else {// 登录成功
// 存到session里
request.getSession().setAttribute("user",
existVoter.getUsername());
// 重定向到成功页面
response.sendRedirect(request.getContextPath() + "/success.jsp");
return;
}
} catch (Exception e) {
e.printStackTrace();
}
}
}
login.jsp登录页面
<%@ page language="java" import="java.util.*" %>
<%@ page contentType="text/html;charset=UTF-8" pageEncoding="UTF-8" %>
登录
${message}
success.jsp登录成功页面
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
登录成功！
Vote类
package cn.sy.servlet;
import java.io.IOException;
import java.sql.SQLException;
import java.text.SimpleDateFormat;
import java.util.Date;
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 cn.sy.domain.User;
import cn.sy.service.UserService;
@WebServlet(name = "VoteServlet", urlPatterns = { "/vote" })
public class Vote extends HttpServlet {
Date currentTime;
SimpleDateFormat formatter;
String dateString = null;
@Override
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
User exsitUser = new User();
String name = request.getParameter("username");
// System.out.println(name);
User user = new User();
user.setName(name);
UserService service = new UserService();
currentTime = new Date();
formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");// 格式化当前时间
dateString = formatter.format(currentTime);// 转成字符串
//从session域中得到当前投票者
String username = (String) request.getSession().getAttribute("user");
//System.out.println(username);
try {
//调用修改记录方法，修改数据库最后投票时间
service.changeRecord(username,dateString);
} catch (SQLException e2) {
e2.printStackTrace();
}
// 调用Service中的查询方法
try {
//查询当前票数
exsitUser = service.findCount(user);
// System.out.println(exsitUser.getCount());
} catch (SQLException e) {
e.printStackTrace();
}
if (exsitUser != null && name.equals("zhaoliu")) {
int count = exsitUser.getCount();// 得到被投人当前票数
count += 1;// 票数加1
try {
service.addCount(name, count);
} catch (SQLException e) {
e.printStackTrace();
}
request.setAttribute("count", "投票成功：" + name + "当前票数为" + count);
//投票成功请求转发到投票页面显示投票成功信息
request.getRequestDispatcher("/vote.jsp")
.forward(request, response);
return;
} else if (exsitUser != null && name.equals("wangwu")) {
int count = exsitUser.getCount();// 得到被投人当前票数
count += 1;// 票数加1
try {
service.addCount(name, count);
} catch (SQLException e) {
e.printStackTrace();
}
request.setAttribute("count", "投票成功：" + name + "当前票数为" + count);
request.getRequestDispatcher("/vote.jsp")
.forward(request, response);
return;
} else {
request.setAttribute("message", "请选中你要投的人！");
request.getRequestDispatcher("/vote.jsp")
.forward(request, response);
return;
}
}
}
vote.jsp投票页面
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme() + "://"
+ request.getServerName() + ":" + request.getServerPort()
+ path + "/";
%>
投票
${message}
Vote_Filter类
package cn.sy.filter;
import java.io.IOException;
import java.sql.SQLException;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import cn.sy.service.UserService;
import cn.sy.domain.Voter;
@WebFilter(filterName = "VoteFilter", urlPatterns = { "/*" })
public class Vote_Filter implements Filter {
Date currentTime;
SimpleDateFormat formatter;
String dateString = null;
@Override
public void doFilter(ServletRequest req, ServletResponse resp,
FilterChain chain) throws IOException, ServletException {
// 1.强制转换
HttpServletRequest request = (HttpServletRequest) req;
HttpServletResponse response = (HttpServletResponse) resp;
// 2.操作
// 判断当前资源是否需要权限控制.
String uri = request.getRequestURI();
String contextPath = request.getContextPath();
String path = uri.substring(contextPath.length());
if (path.equals("/vote") || path.equals("/success")) {
String recordTime = null;
// 判断用户是否登录了.
String voter = (String) request.getSession().getAttribute("user");
UserService service = new UserService();
if (voter == null) {
request.setAttribute("message", "对不起，你还没用登录，请先登录！");
request.getRequestDispatcher("/login.jsp").forward(request,
response);
}
try { // 调用查看当前数据库记录的投票者最后一次投票时间
Voter voter2 = service.findRecord(voter);
recordTime = voter2.getRecord();// 得到时间
currentTime = new Date();
formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");// 格式化当前时间
dateString = formatter.format(currentTime);// 将服务器当前时间转成字符串
try {
Date one = formatter.parse(dateString);
Date two = formatter.parse(recordTime);
long time1 = one.getTime();
long time2 = two.getTime();
long c = time1 - time2;
if(c<24*60*60){
request.setAttribute("message", "对不起，您已经投过票了，明天再来吧！");
request.getRequestDispatcher("/vote.jsp").forward(request,
response);
}
//System.out.println(c);
} catch (ParseException e1) {
//e1.printStackTrace();
System.out.println(voter+"想重复投票！");
}
// System.out.println("最后一次投票时间为："+recordTime);
} catch (SQLException e) {
e.printStackTrace();
}
}
// 3.放行
chain.doFilter(request, response);
}
@Override
public void destroy() {
// TODO Auto-generated method stub
}
@Override
public void init(FilterConfig arg0) throws ServletException {
// TODO Auto-generated method stub
}
}
UserService类
package cn.sy.service;
import java.sql.SQLException;
import cn.sy.dao.UserDao;
import cn.sy.domain.User;
import cn.sy.domain.Voter;
public class UserService {
public Voter login(Voter voter) throws SQLException {
return new UserDao().login(voter);
}
public User findCount(User user) throws SQLException {
return new UserDao().findCount(user);
}
public void addCount(String name,int count) throws SQLException {
new UserDao().addCount(name,count);
}
public void changeRecord(String username, String dateString) throws SQLException {
new UserDao().changeRecord(username, dateString);
}
public Voter findRecord(String voter) throws SQLException {
return new UserDao().findRecord(voter);
}
}
UserDao类
package cn.sy.dao;
import java.sql.SQLException;
import org.apache.commons.dbutils.QueryRunner;
import org.apache.commons.dbutils.handlers.BeanHandler;
import cn.sy.domain.User;
import cn.sy.domain.Voter;
import cn.sy.utils.DBUtils;
public class UserDao {
// 登录
public Voter login(Voter voter) throws SQLException {
String sql = "select * from voter_info where username=? and password=?";
// 使用c3p0数据库连接池，使用封装好的DBUtils获取数据库连接
QueryRunner runner = new QueryRunner(DBUtils.getDataSource());
// BeanHandler(User.class)将结果集中的第一行数据封装到一个对应的JavaBean实例中
// 执行上面写好的sql语句
return runner.query(sql, new BeanHandler(Voter.class),
voter.getUsername(), voter.getPassword());
}
public User findCount(User user) throws SQLException {
String sql = "select count from person_info where name=?";
// 使用c3p0数据库连接池，使用封装好的DBUtils获取数据库连接
QueryRunner runner = new QueryRunner(DBUtils.getDataSource());
// BeanHandler(User.class)将结果集中的第一行数据封装到一个对应的JavaBean实例中
// 执行上面写好的sql语句
return runner.query(sql, new BeanHandler(User.class),
user.getName());
}
public void addCount(String name, int count) throws SQLException {
String sql = "update person_info set count=" + count + " where name=?";
// 使用c3p0数据库连接池，使用封装好的DBUtils获取数据库连接
QueryRunner runner = new QueryRunner(DBUtils.getDataSource());
// BeanHandler(User.class)将结果集中的第一行数据封装到一个对应的JavaBean实例中
// 执行上面写好的sql语句
runner.update(sql, name);
}
public void changeRecord(String username, String dateString)
throws SQLException {
String sql = "update voter_info set record=? where username=?";
// 使用c3p0数据库连接池，使用封装好的DBUtils获取数据库连接
QueryRunner runner = new QueryRunner(DBUtils.getDataSource());
// BeanHandler(User.class)将结果集中的第一行数据封装到一个对应的JavaBean实例中
// 执行上面写好的sql语句
runner.update(sql, dateString,username);
}
public Voter findRecord(String voter) throws SQLException {
String sql = "select * from voter_info where username=?";
QueryRunner runner = new QueryRunner(DBUtils.getDataSource());
return runner.query(sql, new BeanHandler(Voter.class), voter);
}
}
效果图
注意
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