Using Cookies across Activities when using HttpClient

Question

I'm trying a simple app to read in the HTML of a website, and tranform it to create an easily readable UI in Android (This is an exersize in learning android, not to make a useable app). The problem I'm having is persisting a users session across Activities and then using the session in a HttpClient once recalled.

I would like to do this "Correctly", the recommended approach seem to be to use CookieManager. I've had problems with this however - I cannot seem to find the "Correct" way to take a Cookie from the CookieManager and use it in a later instantiation of HttpClient in a seperate Activities.

When using a CookieManager I can save the Cookie and the Cookie is then in scope in other Activities (See code snippet 2). I haven't found how to use this later (See code snippet 3) when requesting a page.

Enough talking, here is some code. First my login action and Cookie storage:

private OnClickListener loginActionListener = new OnClickListener() 
{
    public void onClick(View v) 
    {
        EditText usernameTextView = (EditText) findViewById(R.id.Username);
        EditText passwordTextView = (EditText) findViewById(R.id.Password);
        String username = usernameTextView.getText().toString();
        String password = passwordTextView.getText().toString();

        try {
            HttpPost postMethod = new HttpPost(URI);                
            HttpParams params   = new BasicHttpParams();

            params.setParameter("mode", "login");
            params.setParameter("autologin", true);
            params.setParameter("username", username);
            params.setParameter("password", password);
            postMethod.setParams(params);

            DefaultHttpClient httpClient = new DefaultHttpClient();
            HttpResponse response        = httpClient.execute(postMethod);
            List<Cookie> cookies = httpClient.getCookieStore().getCookies();

            if(cookies != null)
            {
                for(Cookie cookie : cookies)
                {
                    String cookieString = cookie.getName() + "=" + cookie.getValue() + "; domain=" + cookie.getDomain();                        
                    CookieManager.getInstance().setCookie(cookie.getDomain(), cookieString);  
                }
            }
            CookieSyncManager.getInstance().sync();

            Intent intent = new Intent(v.getContext(), IndexAction.class);
            startActivity(intent);
    } catch (Exception e) {...}
}

The startup Activity which decides wether to make the user login or go to the index is below. You can see from this code that the cookie is in scope and can be read:

public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    CookieSyncManager.createInstance(this);

    if(CookieManager.getInstance().getCookie(URI) == null)
    {
        Intent intent = new Intent(this, LoginAction.class);
        startActivity(intent);
    }
    else
    {
        Intent intent = new Intent(this, IndexAction.class);
        startActivity(intent);
    }
}

But from my code to read the Index page I'm hoping you can suggest what i'm missing:

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    CookieSyncManager.createInstance(this);

    try
    {
            HttpGet getMethod = new HttpGet(URI_INDEX);  

            HttpParams params   = new BasicHttpParams();                        
            HttpConnectionParams.setConnectionTimeout(params, 30000);
            HttpConnectionParams.setSoTimeout(params, 30000);

            // This code results in a ClassCastException, I'm assuming i've found a red herring with this solution.
            // HttpContext localContext = new BasicHttpContext();    
            // localContext.setAttribute(ClientContext.COOKIE_STORE, CookieManager.getInstance().getCookie(URI));

            DefaultHttpClient httpClient = new DefaultHttpClient(params);
            HttpResponse response        = httpClient.execute(getMethod);

            if(response.getStatusLine().getStatusCode() > 299 && response.getStatusLine().getStatusCode() < 400)
            {
                // Not logged in doesn't give a redirect response. Very annoying.
            }

            final char[] buffer = new char[0x10000];
            StringBuilder out = new StringBuilder();
            Reader in = new InputStreamReader(response.getEntity().getContent(), "UTF-8");
            int read = 0;
            while (read>=0)
            {
              read = in.read(buffer, 0, buffer.length);
              if (read>0) {
                out.append(buffer, 0, read);
              }
            }

            String returnString = out.toString();
    } catch (ClientProtocolException e) {...}
}

The HttpClient on execute(getMethod) isn't using the Cookie (double checked this in debug) to pull back the page. It would be great if someone could fill this hole in my knowledge.

Thanks in advance.

EDIT

When commented code is added back in (with the httpClient.execute(getMethod) method change to httpClient.execute(getMethod, localContext)) this strack trace is produced - Assumedly because i'm filling the attribute ClientContext.COOKIE_STORE with a Cookie String rather than a CookieStore:

*org.apache.http.client.protocol.RequestAddCookies.process(RequestAddCookies.java:88), org.apache.http.protocol.BasicHttpProcessor.process(BasicHttpProcessor.java:290), org.apache.http.protocol.HttpRequestExecutor.preProcess(HttpRequestExecutor.java:160), org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:401)
org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:555), org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:487), 
com.testapp.site.name.IndexAction.onCreate(IndexAction.java:47), 
android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047), 
android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1611), 
android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1663), 
android.app.ActivityThread.access$1500(ActivityThread.java:117), 
android.app.ActivityThread$H.handleMessage(ActivityThread.java:931), 
android.os.Handler.dispatchMessage(Handler.java:99), 
android.os.Looper.loop(Looper.java:123), 
android.app.ActivityThread.main(ActivityThread.java:3683), 
java.lang.reflect.Method.invokeNative(Native Method), 
java.lang.reflect.Method.invoke(Method.java:507), 
com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839), 
com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597), 
dalvik.system.NativeStart.main(Native Method)*

Answer 1

CookieManager is used by the Java's internal HTTP client. It has nothing to do with Apache HttpClient.

In your code you always create for each request a new instance of HttpClient and therefore a new CookieStore instance, which obviously gets garbage collected along with all cookies stored in as soon as that HttpClient instance goes out of scope.

You should either

(1) Re-use the same instance of HttpClient for all logically related HTTP requests and share it between all logically related threads (which is the recommended way of using Apache HttpClient)

(2) or, at the very least, share the same instance of CookieStore between logically related threads

(3) or, if you insist on using CookieManager to store all your cookies, create a custom CookieStore implementation backed by CookieManager

Answer 2

(As promised a solution to this. I still don't like it and feel like I'm missing out on the "Correct" way of doing this but, it works.)

You can use the CookieManager to register your cookies (and therefore make these cookies available between apps) with the following code:

Saving cookies into the CookieManager:

List<Cookie> cookies = httpClient.getCookieStore().getCookies();

if(cookies != null)
{
    for(Cookie cookie : cookies)
    {
        String cookieString = cookie.getName() + "=" + cookie.getValue() + "; domain=" + cookie.getDomain();                        
        CookieManager.getInstance().setCookie(cookie.getDomain(), cookieString);  
    }
}
CookieSyncManager.getInstance().sync();

Checking for cookies on specified domain: if(CookieManager.getInstance().getCookie(URI_FOR_DOMAIN)

To reconstruct values for HttpClient:

DefaultHttpClient httpClient = new DefaultHttpClient(params);
String[] keyValueSets = CookieManager.getInstance().getCookie(URI_FOR_DOMAIN).split(";");
for(String cookie : keyValueSets)
{
    String[] keyValue = cookie.split("=");
    String key = keyValue[0];
    String value = "";
    if(keyValue.length>1) value = keyValue[1];
    httpClient.getCookieStore().addCookie(new BasicClientCookie(key, value));
}

Answer 3

In my application server wants to use same session with same cookies... After few hours of "googling" and painful headache I just saved cookies to SharedPreference or just put in some object and set DefaultHttpClient with same cookies again ... onDestroy just remove SharedPreferences ... that's all:

1. First copy SerializableCookie class to your package: SerializableCookie

Look the following example:

public class NodeServerTask extends AsyncTask<Void, Void, String> {
private DefaultHttpClient client;


protected String doInBackground(Void... params) {
  HttpPost httpPost = new HttpPost(url);
    List<NameValuePair> urlParameters = new ArrayList<NameValuePair>();
    urlParameters.add(nameValuePair);
    try {
        httpPost.setEntity(new UrlEncodedFormEntity(urlParameters));
        List<Cookie> cookies = loadSharedPreferencesCookie();
        if (cookies!=null){
            CookieStore cookieStore = new BasicCookieStore();
            for (int i=0; i<cookies.size(); i++)
                cookieStore.addCookie(cookies.get(i));
            client.setCookieStore(cookieStore);
        }
        HttpResponse response = client.execute(httpPost);
        cookies = client.getCookieStore().getCookies();

        saveSharedPreferencesCookies(cookies);

// two methods to save and load cookies ...

 private void saveSharedPreferencesCookies(List<Cookie> cookies) {
    SerializableCookie[] serializableCookies = new SerializableCookie[cookies.size()];
    for (int i=0;i<cookies.size();i++){
        SerializableCookie serializableCookie = new SerializableCookie(cookies.get(i));
        serializableCookies[i] = serializableCookie;
    }
    SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(context);
    SharedPreferences.Editor editor = preferences.edit();
    ObjectOutputStream objectOutput;
    ByteArrayOutputStream arrayOutputStream = new ByteArrayOutputStream();
    try {
        objectOutput = new ObjectOutputStream(arrayOutputStream);


        objectOutput.writeObject(serializableCookies);
        byte[] data = arrayOutputStream.toByteArray();
        objectOutput.close();
        arrayOutputStream.close();

        ByteArrayOutputStream out = new ByteArrayOutputStream();
        Base64OutputStream b64 = new Base64OutputStream(out, Base64.DEFAULT);
        b64.write(data);
        b64.close();
        out.close();

        editor.putString("cookies", new String(out.toByteArray()));
        editor.apply();
    } catch (IOException e) {
        e.printStackTrace();
    }
}

private List<Cookie> loadSharedPreferencesCookie() {
    SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(context);
    byte[] bytes = preferences.getString("cookies", "{}").getBytes();
    if (bytes.length == 0 || bytes.length==2)
        return null;
    ByteArrayInputStream byteArray = new ByteArrayInputStream(bytes);
    Base64InputStream base64InputStream = new Base64InputStream(byteArray, Base64.DEFAULT);
    ObjectInputStream in;
    List<Cookie> cookies = new ArrayList<Cookie>();
    SerializableCookie[] serializableCookies;
    try {
        in = new ObjectInputStream(base64InputStream);
        serializableCookies = (SerializableCookie[]) in.readObject();
        for (int i=0;i<serializableCookies.length; i++){
            Cookie cookie = serializableCookies[i].getCookie();
            cookies.add(cookie);
        }
        return cookies;
    } catch (IOException e) {
        e.printStackTrace();
    } catch (ClassNotFoundException e) {
        e.printStackTrace();
    }
    return null;
}

Google Luck

Answer 4

I had the same problem. Since I am using Volley and not HTTPClient directly the Singleton for HTTPClient didn't seem like the correct solution. But using that same idea I simply saved the CookieManager in my application singleton. So if app is my application singleton then in the onCreate() of each activity I add this:

    if (app.cookieManager == null) {
        app.cookieManager = new CookieManager(null, CookiePolicy.ACCEPT_ALL);
    }
    CookieHandler.setDefault(app.cookieManager);

To make this even better, all of my activities are subclasses of MyAppActivity so all I have to do is put it in the onCreate for MyAppActivity and then all of my activities inherit this functionality. Now all my activities are using the same cookie manager and my web service session is shared by all the activities. Simple and it works great.

Answer 5

I suppose one of best thing is apply Singleton Pattern to your HTTPClient so you just have only one instance!

import org.apache.http.client.HttpClient;
import org.apache.http.impl.client.DefaultHttpClient;

public class myHttpClient {
    private static HttpClient mClient;
    private myHttpClient() {};
    public static HttpClient getInstance() {
        if(mClient==null)
            mClient = new DefaultHttpClient();
        return mClient;
    }
}

Answer 6

A good solution for the cookie storage would be to follow the ThreadLocal pattern in order to avoid storing cookies randomly.

This will help keeping a one and only CookieStore. For more explanation of this pattern, you can follow this useful link.

http://veerasundar.com/blog/2010/11/java-thread-local-how-to-use-and-code-sample/

Cheers