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storing cookies in client js and reading in java

I have stored a js array(key value pair) in cookie using JSON.stringify...
Ex:
var a={"aaa":"111","bbb":222};
document.cookie="mycookie="+JSON.stringify(a);
When I'm reading the cookie from js it returns the value for mycookie as a string {"aaa":"111","bbb":222} so I can parse it again using JSON.parse() and it works fine for me.
My need is to get the same cookie from java.. so I used HttpServletRequest's request.getCookie() method. It returns an array of cookies.. while iterating in to that, it does not have the cookie as "mycookie" instead of that it contains the following cookie list
cookie[0]= aaa:
cookie[1]= bbb:
why it does not return a value as
cookie[0]= mycookie:{"aaa":"111","bbb":222}
how does the getcookie method parses a single cookie in this mannar..
JS:
var dateOfVisiting=new Date().getTime().toString();
var mycookie = {‘page’:’example.com’,‘date’:dateOfVisiting};
var expiryDate = new Date();
expiryDate.setTime(expiryDate.getTime()+(30*24*60*60*1000));
var expires = "; expires="+expiryDate.toGMTString();
document.cookie="mycookie="+JSON.stringify(mycookie)+expires+"; path=/;"
Java
Cookie[] cookies = request.getCookies();
String myData = null;
for(Cookie cookie : cookies){
System.out.println(cookie.getName()+“:”+cookie.getValue());
if(“mycookie”.equals(cookie.getName())){
myData = cookie.getValue();
}
}
The result is
page:
date:
And its not getting inside the if condition

Cookie lost on multiple requests (spring mvc + jsp)

I set my cookie in my controller, return a new modelandview, the cookie gets set. However, on any other request, the cookie is lost.
Also, when I reset the cookie to some other value, the value doesn't change when the page is loaded. It does change after page refresh and it again gets lost on any other request.
During all these multiple requests, JSESSIONID remains the same.
In controller:
Cookie locationCookie = new Cookie("locCookie", loc);
locationCookie.setMaxAge(60*60*24*365); //one year
response.addCookie(locationCookie);
return FWD_HOME;
In JSP (FWD_HOME):
<jsp:include page="/WEB-INF/jsp/fragments/header.jsp"></jsp:include>
<jsp:forward page="/HOME"></jsp:forward>
In JSP (header):
<%
Cookie cookie = null;
Cookie[] cookies = null;
cookies = request.getCookies();
String locValue = null;
if( cookies != null ){
for (int i = 0; i < cookies.length; i++){
cookie = cookies[i];
out.print(cookie.getName()+"=");
out.print(cookie.getValue()+";");
if("locCookie".equals(cookie.getName())){
locValue = cookie.getValue();
}
}
}
out.print(locValue);
%>
What am I doing wrong here?

I got the solution. along with Cookies on localhost with explicit domain, setting the path to "/" made it work.

Remember me in jsp login page [duplicate]

This question already has answers here:
How do I keep a user logged into my site for months?
(2 answers)
Closed 5 years ago.
I have a login screen and i am authenticating users by checking credentials from database. But how can i implement Remember me check box? Like in gmail remember me(stay signed in) is present. I am using sign.jsp and Auth servlet (doPost) and oracle 10g ee for authentication.

You can use cookies for this purpose.
In your servlet response handler (doPost, doGet etc.) create a cookie in the following way -
if(remember_me_is_checked)
{
Cookie c = new Cookie("userid", userId.toString());
c.setMaxAge(24*60*60);
response.addCookie(c); // response is an instance of type HttpServletReponse
}
To read them, you can use something like this -
Cookie[] cookies = request.getCookies(); // request is an instance of type
//HttpServletRequest
boolean foundCookie = false;
for(int i = 0; i < cookies.length; i++)
{
Cookie c = cookies[i];
if (c.getName().equals("userid"))
{
string userId= c.getValue();
foundCookie = true;
}
}
Here is the official documentation for the Cookie class.

You can use cookies to help with your implementation. Something like this .
String userIdendificationKey="UserName";
Cookie cookie = new Cookie ("userIdendificationKey",userIdendificationKey);
// Set the age of the cokkie
cookie.setMaxAge(365 * 24 * 60 * 60);
//Then add the cookies to the response
response.addCookie(cookie);
and then check against the particular value later .

I don't know whether it is secure or not,but this is what i did.
In login.jsp head tag
<script type="text/javascript">
var isLoggedIn = "${isLoggedIn}";
if(isLoggedIn === true)
window.location.href="Home.jsp";
</script>
in body tag i added a check box for Remember Me as below
<input type="checkbox" id="RememberMe" name="rememberMe">
<label for="RememberMe">Remember Me</label>
In servlet doPost method i added the code below
if(userdetails are verified)
{
if(request.getParameter("rememberMe")!=null){
request.getSession().setAttribute("isLoggedIn", true);
}
RequestDispatcher rs = request.getRequestDispatcher("Home.jsp");
rs.forward(request, response);
}
else
{
RequestDispatcher rs = request.getRequestDispatcher("fail.jsp");
rs.include(request, response);
}
using this it will ask for the credentials at first time login,and it will store the login info in session parameters,if you try to access the site second time it will automatically goes to "Home.jsp" instead of "login.jsp"
please comment whether this method is good practice,any other modifications can be done.
Suggestions are welcome.

Take a look at Spring SecurityIt
It is a powerful and highly customizable authentication and access-control framework.
You can also check the code from Rose India, this will be more helpful to you.

how to recieve all the parameters from XMLHttpRequest request on server side?

I am using XMLHttpRequest to create a simple form submit and pass 2 parameters. On the server side I am receiving both the parameters but how to get them in different variables?
Here is the Servlet
PrintWriter out = response.getWriter();
response.setContentType("text/plain");
paramMap=request.getParameterMap();
if (paramMap == null)
throw new ServletException(
"getParameterMap returned null in: " + getClass().getName());
iterator=paramMap.entrySet().iterator();
System.out.println(paramMap.size());
String str="";
while(iterator.hasNext())
{
Map.Entry me=(Map.Entry)iterator.next();
String[] arr=(String[])me.getValue();
configId=arr[0];
System.out.println(me.getKey()+" > "+configId);
}
/***Above println** i get "name > Abhishek,filename=a.txt*/
rand=new Random();
randomInt=rand.nextInt(1000000);
configId=randomInt+configId;
System.out.println(configId);
out.println(configId);
/*creates a new session if a session does not exist already*/
session=request.getSession();
session.setAttribute("cid", configId);
out.close();
/*I also need to check a session name `uid` i.e., already created before calling this servlet and then only get both the parameters in parameterMap and store all the params in session. so i'd like to do something like this */
session=request.getSession(false);
if(session!=null) //then get all the parameters here and store them into session
{
uid=session.getAttribute("uid").toString();
/*get nameFromTheParameterMap and fileNameFromTheParameterMap from paramt
session.setAttribute("name", nameFromTheParameterMap);
session.setAttribute("filename", fileNameFromTheParameterMap);
}
Is this the correct approach? Also how will I get parameters from dataString to parameterMap
here is the saveConfig function
function saveConfig()
{
var url_action="/temp/SaveConfig";
var client;
var dataString;
if (window.XMLHttpRequest){ // IE7+, Firefox, Chrome, Opera, Safari
client=new XMLHttpRequest();
} else { // IE6, IE5
client=new ActiveXObject("Microsoft.XMLHTTP");
}
client.onreadystatechange=function(){
if(client.readyState==4&&client.status==200)
{
alert(client.responseText);
}
};
dataString="name="+document.getElementById("name").value+",filename="+document.getElementById("tfile").value;
client.open("POST",url_action,true);
client.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
client.send(dataString);
}

You are wrongly encoding the form-data, you have to seperate the fields by & and not by ,.
See Wikipedia for a summary:
This is a format for encoding key-value pairs with possibly
duplicate keys. Each key-value pair is
separated by an '&' character, and
each key is separated from its value
by an '=' character.
BTW, your Java-Code looks verbose, you could simplify by using for-each-loops.

creating login and welcomenpages using JSP

I want to create a login page thats when the user select either remember username or remember me check box, a cookie should be generated, when the remember username checkbox is selected, it should store the username, when the remember me checkbox is selected it should store both the username and password to avoid retyping whena user returns to the login page.
I wrote the preceeding code to incorporate the functionality but on testing the page the user has to retype the username each time the login page is loaded. I am not able to identify the cause of the problem, can someone help me with this?
<%
String userName = request.getParameter("username");
String password = request.getParameter("password");
String rm_me = request.getParameter("rm_me");
String rm_uname = request.getParameter("rm_uname");
if (userName != null && password != null) {
if (rm_me != null) {
Cookie ckU = new Cookie("username", userName);
Cookie ckP = new Cookie("password", password);
response.addCookie(ckP);
} else {
if (rm_uname != null) {
Cookie ckU = new Cookie("username", userName);
}
}
Cookie[] cookies = request.getCookies();
if (cookies != null) {
for (int i = 0; i < cookies.length; i++) {
if (cookies[i].getName().equals("username")) {
userName = cookies[i].getValue();
}
if (cookies[i].getName().equals("password")) {
password = cookies[i].getValue();
}
}
}
%>

You shouldn't be doing this kind of stuff in a JSP. You should use do it in a "controller" servlet and then forward the outcome to a JSP to (just) format the HTML response.
And I think your problem is most likely to be related to that. Specifically, I suspect that the response will already have been committed by the time that the scriptlet code executes. This means that your response.addCookie(...); call will be too late to add a SetCookie header to the response.
You should be able to confirm this by dumping the response headers when they leave the server or when they reach your browser ... or (less directly) by looking in the browser cookie store.

Pretty much any introductory book or tutorial on JSP would include examples of everything you want.
Any reasonably recent one will also tell you that using Java code in a JSP is very bad indeed, just don't do it.
Use JSTL instead.