JavaWeb_利用Cookie技术实现自动登录

//------------------------------------存储Cookie-------------------------------
package com.MainServlet;

import java.io.File;
import java.io.IOException;

import javax.servlet.ServletException;
import javax.servlet.annotation.MultipartConfig;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.Part;

/**
* Servlet implementation class MainServlet
*/
@WebServlet(name = "/MainSerlet", urlPatterns = { "/Login", "/Result", "/SH" })
@MultipartConfig(location = "D:\\", fileSizeThreshold = 10 * 1024)
public class MainServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
private String username = null;

/**
* @see HttpServlet#HttpServlet()
*/
public MainServlet() {
super();
// TODO Auto-generated constructor stub
}

/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse
*      response)
*/
protected void doGet(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
response.setContentType("text/html;charset=UTF-8");
String uri = request.getRequestURI();
if (uri.endsWith("/Login")) {
String username = request.getParameter("username");
String password = request.getParameter("password");
String checked = "checked";
if (!username.equals("Admin") || !password.equals("123")) {
response.sendRedirect("Login.jsp");
}else{
if ((request.getParameter("checkbox") != null)
&& (request.getParameter("checkbox").equals("1"))) {
Cookie namecookie = new Cookie("username", username);
Cookie wordcookie = new Cookie("password", password);
Cookie checkedcookie = new Cookie("checked", checked);
namecookie.setMaxAge(3600);
wordcookie.setMaxAge(3600);
checkedcookie.setMaxAge(3600);
response.addCookie(namecookie);
response.addCookie(wordcookie);
response.addCookie(checkedcookie);

}
request.getSession().setAttribute("AAA", username);
response.sendRedirect("LoginPage.jsp");
}
} else if (uri.endsWith("/Result")) {
Result(request, response);
} else if (uri.endsWith("/SH")) {
SH(request, response);
}
}

/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse
*      response)
*/
protected void doPost(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
doGet(request, response);
}

protected void Result(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
String quest1 = request.getParameter("quest1");
// System.out.println(quest1);
String quest2 = request.getParameter("quest2");
String[] quest3 = request.getParameterValues("quest3");
String quest4 = request.getParameter("quest4").trim();
int score = 0;
if (quest1 != null && quest1.equals("1")) {
score += 25;
}
if (quest2 != null && quest2.equals("3")) {
score += 25;
}
if (quest3 != null && quest3.length == 2 && quest3[0].equals("1")
&& quest3[1].equals("3")) {
score += 25;
}
if (quest4 != null && quest4.equals("HttpServlet")
|| quest4.equals("javax.servlet.http.HttpServlet")) {
score += 25;
}
// System.out.println(score);
request.getSession().setAttribute("score", score);
request.getSession().setAttribute("username", username);
response.sendRedirect("Score.jsp");
}

protected void SH(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
String path = "D:" + "\\" + request.getParameter("number");
Part p = request.getPart("filename");
String message = null;
File f = new File(path);
if (!f.exists()) {
f.mkdirs();
}
// String h = p.getHeader("content - disposition");
// System.out.println(h);
// String name = h.substring(h.lastIndexOf("\\")+1, h.length()-1);
// System.out.println("aaa");
p.write(path + "\\" + request.getParameter("number") + ".JPG");
message = "文件上传成功";
double size = p.getSize() * 1.0 / 1024 / 1024;
request.getSession().setAttribute("message", message);
request.getSession().setAttribute("username", username);
request.getSession().setAttribute("size", size + "");
response.sendRedirect("SHS.jsp");
}

}

<pre name="code" class="java"><!------------------------读取Cookie----------------------------------->
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<link href="Test.css" type="text/css" rel="stylesheet"></link>
<title>登录界面</title>
</head>
<body>
<%
String value1 = "";
String value2 = "";
String value3 = "";
Cookie cookie = null;
boolean flag = false;
Cookie[] cookies = request.getCookies();
if (cookies != null) {
for (int i = 0; i < cookies.length; i++) {
cookie = cookies[i];
if (cookie.getName().equals("username")) {
value1 = cookie.getValue();
}
if (cookie.getName().equals("password")) {
value2 = cookie.getValue();
}
if (cookie.getName().equals("checked")) {
value3 = cookie.getValue();
}
}

}
%>

<div class="Login" style="background: url('Images/Face.jpg');">
<h1 align="center" style="margin-top: 80px">登录界面</h1>
<form action="Login" method="post">
<table border="1" align="center"
style="border-collapse: collapse; width: 300px; height: 120px; margin-top: 60px;">
<tr>
<td align="center" style="font-size: 15px;">用户名</td>
<td><input type="text" name="username" value="<%=value1%>" /></td>
</tr>
<tr>
<td align="center" style="font-size: 15px;">密    码</td>
<td><input type="password" name="password" size="21"
value="<%=value2%>" /></td>
</tr>
<tr>
<td> </td>
<td style="font-size: 15px;"><input type="checkbox"
name="checkbox" value="1" size="25" checked="<%=value3%>"/>自动登录</td>
</tr>
<tr>
<td></td>
<td><input type="submit" value="登录" />        <input
type="reset" value="重置" /></td>
</tr>
</table>
</form>
</div>
</body>
</html>