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How to get session token form url?

Lets say..
if i hit google with https://www.google.com it will create a session, for the responce it
will create url with session tokn like..
https://www.google.co.in/?gfe_rd=cr&ei=oFBjVJSvLqnM8gft5YDwAQ&gws_rd=ssl.
My question is
am connecting to google with the code:
URL url = new URL(test);
URLConnection conn = url.openConnection();
this will connect to google.
for this google creates a session.
then how would i get a session token back to my code?

You can get the session token from the cookie of the browser. You can, find the cookie settings->advanced settings->privacy->content settings->allcookie and site data then search www.google.com and select sid and copy the content .

You can extract any cookie, not only the one containing the session with the following approach:
Since a server may set multiple cookies in a single request, we will need to loop through the response headers, looking for all headers named "Set-Cookie".
String headerName=null;
for (int i=1; (headerName = uc.getHeaderFieldKey(i))!=null; i++) {
if (headerName.equals("Set-Cookie")) {
String cookie = urlConn.getHeaderField(i);
The string returned by the getHeaderField(int index) method is a series of name=value separated by semi-colons (;). The first name/value pairing is actual data string we are interested in (i.e. "sessionId=0949eeee22222rtg"), the subsequent name/value pairings are meta-information that we would use to manage the storage of the cookie (when it expires, etc.).
cookie = cookie.substring(0, cookie.indexOf(";"));
String cookieName = cookie.substring(0, cookie.indexOf("="));
String cookieValue = cookie.substring(cookie.indexOf("=") + 1, cookie.length());
This is basically it. We now have the cookie name (cookieName) and the cookie value (cookieValue).
the above explanation was based on example provided in http://www.hccp.org/java-net-cookie-how-to.html#retrieving_cookies
A more sophisticated approach is to use CookieAccessor class:
public void getCookieUsingCookieHandler() {
try {
// Instantiate CookieManager;
// make sure to set CookiePolicy
CookieManager manager = new CookieManager();
manager.setCookiePolicy(CookiePolicy.ACCEPT_ALL);
CookieHandler.setDefault(manager);
// get content from URLConnection;
// cookies are set by web site
URL url = new URL("http://host.example.com");
URLConnection connection = url.openConnection();
connection.getContent();
// get cookies from underlying
// CookieStore
CookieStore cookieJar = manager.getCookieStore();
List <HttpCookie> cookies =
cookieJar.getCookies();
for (HttpCookie cookie: cookies) {
System.out.println("CookieHandler retrieved cookie: " + cookie);
}
} catch(Exception e) {
System.out.println("Unable to get cookie using CookieHandler");
e.printStackTrace();
}
}
In any approach you follow you need to know what is the name of the cookie holding the session id, so that you can get the value from it. E.g a java web application usually creates a cookie with name "JSESSIOINID"

Setting cookie in JSP and retrieving from non servlet class

I have a situation where i need to set cookie in JSP and i need to get those cookie in normal java class.
The JSP:
CookieManager manager = new CookieManager();
CookieHandler.setDefault(manager);
CookieStore cookieJar = manager.getCookieStore();
// create cookie
HttpCookie cookie = new HttpCookie("UserName", "John Doe");
// add cookie to CookieStore for a
// particular URL
URL url = new URL("http://localhost:8080");
url.openConnection().connect();
cookieJar.add(url.toURI(), cookie);
System.out.println("Added cookie using cookie handler");
%>
Below is the Java class [not a servlet class] and this class is running in the server and this is invoked not after the JSP call but somewhere in the application only if any event occurs. below is the code where i wrote to capture cookies.
URL url = new URL("http://localhost:8080");
URLConnection conn = url.openConnection();
conn.getContent();
CookieManager cm = new CookieManager();
CookieHandler.setDefault(cm);
cm.setCookiePolicy(CookiePolicy.ACCEPT_ALL);
CookieStore cs = cm.getCookieStore();
List <HttpCookie> cookies = cs.getCookies();
for (HttpCookie cookie: cookies) {
System.out.println("CookieHandler retrieved cookie: " + cookie);
}
would this scenario works if i want to retrieve the cookies in non servlet class?
The output of the above code will return empty list.
However if i write a servet class with request.getCookie("UserName") I will see the cookie value.
Here i need to understand how would i get the cookie value without using request object.
Because request object is not always passed in multiple invocation of java class. And i am not using session.
please let me know if you have any better approach.
Thanks-

Instead Use the getHeaderFields() method from the connection Object to get the full list of Name-Value pairs representing the header fields of the specific connection
Cookie information(if present)should be under the “Set-Cookie” header field.
Map<String, List<String>> headerFields = conn.getHeaderFields();
Set<String> headerFieldsSet = headerFields.keySet();
Iterator<String> hearerFieldsIter = headerFieldsSet.iterator();
Then iterate over the Set and check if the cookie is present. If it is present print it out.
while (hearerFieldsIter.hasNext()) {
String headerFieldKey = hearerFieldsIter.next();
if ("Set-Cookie".equalsIgnoreCase(headerFieldKey)) {
List<String> headerFieldValue = headerFields.get(headerFieldKey);
for (String headerValue : headerFieldValue) {
System.out.println("Cookie Found...");
String[] fields = headerValue.split(";\s*");
String cookieValue = fields[0];
System.out.println("cookieValue:" + cookieValue);
}
}
}
Y0u can refer this examle

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.

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.

How do you update an existing cookie in JSP?

I have a cookie, myCookie, that contains a hash value. This cookie is set to expire in one year and has a path of '/'. I need to update this cookie with a new hash value. When my JSP script is loaded I retrieve the cookie like so:
Cookie[] cookies = request.getCookies();
Cookie myCookie = null;
for (int i = 0; i < cookies.length; i += 1) {
if (cookies[i].getName().equals("myCookie")) {
myCookie = cookies[i];
break;
}
}
After determining that the value of the cookie needs to be updated, I do the following to update it:
myCookie.setValue("my new value");
response.addCookie(myCookie);
Examining the results, I now have two instances of myCookie: the original version with the correct expiration date and path, and the old, invalid, value; and a new cookie named "myCookie" that expires at the end of the session, with the correct value, and a path of the JSP document.
If I do:
myCookie.setValue("my new value");
myCookie.setPath(myCookie.getPath());
myCookie.setMaxAge(myCookie.getMaxAge());
response.addCookies(myCookie);
The same thing happens. I get two cookies with the same name and different properties.
Does a Cookie object not retain the properties from when it was retrieved? How can I update this cookie?
Note: I do not want to modify the path or the expiration date. I only want to update the value of the already set cookie.

Per section 3.3.4 of RFC 2965, the user agent does not include the expiration information in the cookie header that is sent to the server. Therefore, there is no way to update an existing cookie's value while retaining the expiration date that was initially set based solely on the information associated with the cookie.
So the answer to this question is: you can't do that.

Just set the path, ex:
cookie.setPath("/");
This should overwrite the old cookie value.

If you are manipulating cookies from within a JSP, one thing you will need to watch out for is whether or not the response has already been committed. Once content is written to the output stream, adding a cookie to the response is futile.
ServletResponseWrapper.isCommitted()

You can delete the old cookie, if the new one does not contain the same name, path, and domain by setting MaxAge to (0) http://download.oracle.com/javaee/1.3/api/javax/servlet/http/Cookie.html#setMaxAge(int)

def member = SecUser.get(userService.currentUser().id)
def cookies = request.getCookies()
def cookie;
def sum = 0;
def cookieSum = 0;
def cookieItems;
for(def i=0; i<cookies.size(); i++){
if (cookies[i].name == 'c17'){
cookie = cookies[i]
cookieItems = cookie.value.split('-')
println "cookieItems......."+cookieItems
if(params.itemId != null){
for(def j=0; j<cookieItems.size(); j++){
def oldItem = cookieItems[j].split('\\|')[0]
if(params.itemId != oldItem){
sum = sum + 1
}
}//Below code for Update your cookie value
if(sum == cookieItems.size()){
cookie.value = cookie.value +"-"+params.itemId+"|"+member.id
def b = cookie.value
cookie.setValue(b);
response.addCookie(cookie);
}
}
break
}
else{
cookieSum = cookieSum + 1
}
}
if ((cookieSum) == cookies.size()){
// Here ADD new cookie........
def a = params.itemId+"|"+member.id
cookie = new Cookie('c17',a.toString())
cookie.path = '/'
response.addCookie(cookie)
}
The Above code can help you for ADD a cookie and UPDATE the cookie value