jsp4 Cookie

(1)

（2）Session----Coolie

(3)

(4)

cookie保存

index.jsp

<%@ page language="java" import="java.util.*,java.net.*"  contentType="text/html; charset=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">
  </head>
  
  <body>
 
		<h1>用户登录</h1>
		<hr>
			<%
			 request.setCharacterEncoding("utf-8");
		String username = "";
		String password = "";
		Cookie[] cookies = request.getCookies();
		if (cookies != null && cookies.length > 0) {
			for (Cookie c : cookies) {
				if (c.getName().equals("username")) {//(名称)
					username=URLDecoder.decode(c.getValue(),"utf-8");
				}
				if( c.getName().equals("password")){
					password=URLDecoder.decode(c.getValue(),"utf-8");
				}
			}
		}
	%>
			<form action="dologin.jsp" method="post" name="loginForm">
			<table>
			  <tr><td>用户名：</td><td><input type="text" name="username" value="<%=username %>" /> </td></tr>
			   <tr><td>密码：</td><td><input	type="password" name="password" value="<%=password %>" /></td></tr>
			    <tr><td colspan="2" ><input type="checkbox" name="isUseCookie" checked="checkd" />十天内记住登陆状态</td></tr>
			    <tr><td colspan="2" aligin="center"><input type="submit" value="登录"></td></tr>
			</table>
				
			</form>
		
  </body>
</html>

dologin.jsp

<%@ page language="java" import="java.util.*,java.net.*"  contentType="text/html; charset=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 'dologin.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">
  </head>
  
  <body>
    <h1>登陆成功</h1> <br><br><br><br>
    <%
    request.setCharacterEncoding("utf-8");//防止中文乱码
       //首先判断用户是否选择了记录登陆状态
       String[] isUseCookie=request.getParameterValues("isUseCookie");//返回包含参数name的所有值的数组
       if(isUseCookie!=null&&isUseCookie.length>0){
    	   //吧用户名和密码保存在Cookie对象里面
    	   String username= URLEncoder.encode(request.getParameter("username"),"utf-8");//返回name指定函数的参数值
    	   //URLEncoder.encode(s, enc)防止中文乱码。。短码
    	   String password= URLEncoder.encode(request.getParameter("password"),"utf-8");  
    	 
    	   Cookie usernameCookie=new Cookie("username",username);//创建cookie对象
    	   Cookie passwordCookie=new Cookie("password",password);
    	   usernameCookie.setMaxAge(8640000);//设置最大生存期限为10天(有效期)
    	   passwordCookie.setMaxAge(8640000);
    	   response.addCookie(usernameCookie);//加入cookie对象
    	   response.addCookie(passwordCookie);
       }else{
    	   Cookie[] cookies=request.getCookies();//读取cookie对象
    	   if(cookies!=null&&cookies.length>0){
    		   for(Cookie c:cookies){
    			   if(c.getName().equals("username")||c.getName().equals("password")){//(名称)
    				   c.setMaxAge(0);//设置cookie失效
    			        response.addCookie(c);//重新保存
    			   }
    		   }
    	   }
       }
    %>
    <a href="users.jsp" target="_blank">查看用户信息</a>
  </body>
</html>

users.jsp

<%@ page language="java" import="java.util.*,java.net.*"
	contentType="text/html; charset=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 'users.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">
</head>
<body>
	<h1>用户信息</h1>
	<br>
	<br>
	<br>
	<br>
	<%
	 request.setCharacterEncoding("utf-8");
		String username = "";
		String password = "";
		Cookie[] cookies = request.getCookies();
		if (cookies != null && cookies.length > 0) {
			for (Cookie c : cookies) {
				if (c.getName().equals("username")) {//(名称)
					//解码用URLDecoder.decode(s, enc)
					username=URLDecoder.decode(c.getValue(),"utf-8");
				}
				if( c.getName().equals("password")){
					password=URLDecoder.decode(c.getValue(),"utf-8");
				}
			}
		}
	%>
	用户名：<%=username %>
	<br> 密码：<%=password %>
	<br>
</body>
</html>

(5)Session-Cookie

来自为知笔记(Wiz)

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原文地址：https://www.cnblogs.com/liuruimiku/p/5459225.html