Tuesday, July 17, 2012

Session Management in Android

Wanted to maintain Session, i.e. Session Management in Android.

This has nothing to do with Android. It has everything to do with Apache HttpClient, the library you are using for HTTP access.
Session cookies are stored in your DefaultHttpClient object. Instead of creating a newDefaultHttpClient for every request, hold onto it and reuse it, and your session cookies will be maintained.
Generally, in Java HttpURLConnection you can set / get a cookie this way (here is the whole connection process). The code below is in my ConnectingThread's run(), from which all the connecting activity classes inherit. All share common static sCookie string which is sent with all the requests. Therefore you can maintain a common state like being logged on / off:


   HttpURLConnection conn = (HttpURLConnection) url.openConnection();             

        //set cookie. sCookie is my static cookie string
        if(sCookie!=null && sCookie.length()>0){
            conn.setRequestProperty("Cookie", sCookie);                  
        }

        // Send data
        OutputStream os = conn.getOutputStream(); 
        os.write(mData.getBytes());
        os.flush();
        os.close(); 

        // Get the response!
        int httpResponseCode = conn.getResponseCode();         
        if (httpResponseCode != HttpURLConnection.HTTP_OK){
           throw new Exception("HTTP response code: "+httpResponseCode); 
        }

        // Get the data and pass them to the XML parser
        InputStream inputStream = conn.getInputStream();                
        Xml.parse(inputStream, Xml.Encoding.UTF_8, mSaxHandler);                
        inputStream.close();

        //Get the cookie
        String cookie = conn.getHeaderField("set-cookie");
        if(cookie!=null && cookie.length()>0){
            sCookie = cookie;              
        }

        /*   many cookies handling:                  
        String responseHeaderName = null;
        for (int i=1; (responseHeaderName = conn.getHeaderFieldKey(i))!=null; i++) {
            if (responseHeaderName.equals("Set-Cookie")) {                  
            String cookie = conn.getHeaderField(i);   
            }
        }*/                

        conn.disconnect();                

For Details - 
You can read about Apache HttpClient and read about cookie management in HttpClient


You need to use HttpContext. Set cookie store to context and pass context long with HttpGet/HttpPost in execute method. Hope this should help.
  // Create a local instance of cookie store
    CookieStore cookieStore = new BasicCookieStore();

    // Create local HTTP context
    HttpContext localContext = new BasicHttpContext();
    // Bind custom cookie store to the local context
    localContext.setAttribute(ClientContext.COOKIE_STORE, cookieStore);

    HttpGet httpget = new HttpGet("http://www.google.com/"); 

    System.out.println("executing request " + httpget.getURI());

    // Pass local context as a parameter
    HttpResponse response = httpclient.execute(httpget, localContext);

Follow below link -