Develop Reference

Android HTTPS Request

I have tried so many options, I'm going to go crazy. I continue to get an SSL exception every time I try to post to a URL.
This works like a dream in C# using an HttpWebRequest.
The errors I get are:
Not trusted server certificate
java.security.cert.CertPathValidatorException: TrustAnchor for CertPath not found.
I am trying the following approach now, but I have tried custom SocketFactories, everything. Please help!
final String httpsURL = "https://...";
final DefaultHttpClient client = new DefaultHttpClient();
final HttpPost httppost = new HttpPost(httpsURL);
//authentication block:
final List<BasicNameValuePair> nvps = new ArrayList<BasicNameValuePair>();
nvps.add(new BasicNameValuePair("mail", username));
nvps.add(new BasicNameValuePair("password", password));
UrlEncodedFormEntity p_entity = null;
try {
p_entity = new UrlEncodedFormEntity(nvps, HTTP.UTF_8);
} catch (UnsupportedEncodingException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
httppost.setEntity(p_entity);
//sending the request and retrieving the response:
HttpResponse response = null;
try {
response = client.execute(httppost, _context);
} catch (ClientProtocolException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
HttpEntity responseEntity = response.getEntity();
//handling the response: responseEntity.getContent() is your InputStream
try {
final InputSource inputSource = new InputSource(responseEntity.getContent());
} catch (IllegalStateException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

You need to consider how Android determines the validity of certificates. When it needs to verify a certificate, it will look at the chain of signatures. If it can find a trusted authority at its top, and the certificate not being on the revocation list, then it will be trusted.
To reduce time-intensive queries, Android comes bundled with a list of common CAs that it trusts. As you noted in the comments, the error disappeared when you upgraded. This is most likely due to the CA you were using being added to the list of shipped trusted CAs.
You can, if you trust the certificate, add it to this list of trusted CAs. The accepted answer to this question has some details on this procedure for older versions! Newer versions are more likely to come shipped with the certificates you will need. With newer versions, you can install certificates directly from your SD card. Go to Settings -> Security. Under Credential storage you will find the option Install from device storage. As long as you are using a standard format, you should be able to install your certificate!
My source: Security with HTTPS and SSL | Android Developers

How to delete Auth Token From Application Class For sign Out Functionality in Twitter app in android

I Want to remove Auth token from Application Class,In My Twitter app How can I do this Please help me
Thank You

there is no need to remove auth token, u just need to post one query to twitter api as follow. it will delete all store cookies and tokens stored by twitter.
public void logoutToTwitter() {
// Create a new HttpClient and Post Header
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost("http://api.twitter.com/1/account/end_session.format");
try {
// Execute HTTP Post Request
httpclient.execute(httppost);
} catch (ClientProtocolException e) {
// TODO Auto-generated catch block
} catch (IOException e) {
// TODO Auto-generated catch block
} }
just call the above method on your "twitter logout button"
enjoy the code.

TwitterApp mTwitter = new TwitterApp(MyProfile.this, Constants.TWITTER_CONSUMER_KEY,
Constants.TWITTER_SECRET_KEY);
mTwitter.resetAccessToken();
This much worked well for me, ussing the twitter4j. Just calling the resetAccessToken is equivalent to logout.

UnknownHostException is thrown in android app if hostname is used instead of IP address

I have the following code which I use to send a request to the server.
String inputXML = createInputXML(searchText);
HttpClient httpclient = new DefaultHttpClient();
String url = "http://mysite.com/action";//Works fine if I use IP address directly,for eg:http://1.2.3.4/action
HttpPost httppost = new HttpPost(url);
HttpResponse response=null;
StringEntity se = null;
try {
se = new StringEntity(inputXML, HTTP.UTF_8);
} catch (UnsupportedEncodingException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
se.setContentType("text/xml");
httppost.setHeader("Content-Type","application/xml;charset=UTF-8");
httppost.setEntity(se);
try {
response = httpclient.execute(httppost);
} catch (ClientProtocolException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
When I run the program on emulator I am getting a UnKnownHostException on the line
response = httpclient.execute(httppost);
If I use the ip address directly instead of host name,the request is sent correctly.
Please note the following points:
I am using Android 2.3.3
I have added <uses-permission android:name="android.permission.INTERNET"></uses-permission> in the manifest xml
Proxy settings are updated in the emulator's APN.
Using the browser in the emulator I can access a website with their host names.
Any idea why this is causing an issue?

Please make sure, you followed all steps 1-4 user700284 described in his Question.
HttpClient client = new DefaultHttpClient();
//Get the default settings from APN (could be also hard coded stuff)
String proxyHost = android.net.Proxy.getDefaultHost();
int proxyPort = android.net.Proxy.getDefaultPort();
//Set Proxy params of client, if they are not the standard
if (proxyHost != null && proxyPort > 0) {
HttpHost proxy = new HttpHost(proxyHost, proxyPort);
client.getParams().setParameter(ConnRoutePNames.DEFAULT_PROXY, proxy);
}
HttpGet request = new HttpGet("http://www.google.com");

The url has nothing to do with the line
se = new StringEntity(inputXML, HTTP.UTF_8);
are you sure it is this line?

Web Service using HTTP Protocol in Android

can anyone give me an idea of using web service using HTTP protocol.

Here is an example for "Executing a HTTP POST Request with HttpClient":
public void postData() {
// Create a new HttpClient and Post Header
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost("http://www.yoursite.com/script.php");
try {
// Add your data
List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(2);
nameValuePairs.add(new BasicNameValuePair("id", "123"));
nameValuePairs.add(new BasicNameValuePair("username", "Paresh"));
httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
// Execute HTTP Post Request
HttpResponse response = httpclient.execute(httppost);
} catch (ClientProtocolException e) {
// TODO Auto-generated catch block
} catch (IOException e) {
// TODO Auto-generated catch block
}
}

We can use web services in our application to send and receive data from a remote server. Consider the case of an login section from a application where you need to pass username and password to the server for checking the whether the user is a valid user or not. In this case the username and password are attached with a url and send it to the remote server for validation and in response you get a value stating whether the user is a valid user or not. Usually the response will be either in XML format or JSON format from there we need to parse that response to get the necessary values. Check out the following example code in this I have created a class named "parsing" and it using the http protocol to receive a data.
public class parsing extends Activity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
try {
HttpClient client = new DefaultHttpClient();
String postURL = "http://services.digg.com/topics?appkey=http://example.com&type=json";
HttpPost post = new HttpPost(postURL);
HttpResponse responsePOST = client.execute(post);
HttpEntity resEntity = responsePOST.getEntity();
String response=EntityUtils.toString(resEntity);
response=response.trim();
Log.i("RESPONSE=",response);
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
See the response on the Logcat and do not for get to include <uses-permission android:name="android.permission.INTERNET" />
because we are fetching the data from the remote server which needs internet permission.

Why doesn't HttpClient work but HttpUrlConnenction do when posting data to form

I'm building an android app which should perform a GET on my site to get two cookies and then perform a post to the same site with these cookies.
As mentioned I start of with the GET and I'm using org.apache.http.client.HttpClient to perform this operation.
String requiredCookies = "";
HttpContext localContext = null;
System.out.println("------------------GET----------------------");
HttpClient httpClient = new DefaultHttpClient();
HttpGet get = new HttpGet("www.mysitegeturl.com");
//Creating a local instance of cookie store.
CookieStore cookieJar = new BasicCookieStore();
// Creating a local HTTP context
localContext = new BasicHttpContext();
// Bind custom cookie store to the local context
localContext.setAttribute(ClientContext.COOKIE_STORE, cookieJar);
HttpResponse response;
try {
response = httpClient.execute(get, localContext);
HttpEntity entity = response.getEntity();
System.out.println(response.getStatusLine());
if (entity != null) {
System.out.println("Response content length: " + entity.getContentLength());
}
//Do this so that Java.net impl should work
List<Cookie> cookies = cookieJar.getCookies();
for (int i = 0; i < cookies.size(); i++) {
requiredCookies += cookies.get(i).getName()+"="+cookies.get(i).getValue()+";";
}
if (entity != null) {
entity.consumeContent();
}
} catch (ClientProtocolException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
} catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
System.out.println("------------------GET-END---------------------");
So far so good. Don't mind the requiredCookies line yet, it will be used in the Java.net impl since I can't get the HttpClient one to work =(.
Let's take a look at the non working HttpClient Post part.
System.out.println("------------------HttpClient - POST----------------------");
HttpPost post = new HttpPost("www.mysiteposturl.com");
//Params
HttpParams params = new BasicHttpParams();
params.setParameter("foo", "post");
params.setParameter("bar", "90");
params.setParameter("action", "search");
post.setParams(params);
post.setHeader("Content-Type", "application/x-www-form-urlencoded");
try {
HttpResponse response2 = httpClient.execute(post, localContext);
System.out.println(response2.getStatusLine());
} catch (ClientProtocolException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
System.out.println("------------------POST END---------------------");
What happens now is that I perform a POST with the localContext where the cookies are stored. This doesn't work. I get a HTTP/1.1 401 No session. Since I had no luck with this I tried another approach(java.net.HttpURLConnection). Remember I still use the same GET part
URL url = new URL("www.mysiteposturl");
HttpURLConnection connection = null;
String dataString = "bar=90&foo=post&action=search";
try {
connection = (HttpURLConnection)url.openConnection();
connection.setRequestProperty("Cookie", requiredCookies);
//Set to POST
connection.setDoOutput(true);
Writer writer = new OutputStreamWriter(connection.getOutputStream());
writer.write(dataString);
writer.flush();
writer.close();
connection.connect();
if (connection.getResponseCode() == 200 || connection.getResponseCode() == 201) {
System.out.println(connection.getContent().toString());
} else {
System.out.println("Error");
}
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (MalformedURLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
System.out.println("------------------POST END---------------------");
And VIOLA a 200 is displayed and everything works like a charm. What do you guys think? Could someone please provide me with an answer because I can't figure it out.

The problem appears to be that you have two different host names in the setup. This will cause HTTP Client to not send cookies for a different host. You could try changing the domain of the cookies in the cookie store, or using the same host for GET and POST. Additionally you could manually add the cookies to the headers in HTTP Client as you did in the HttpURLConnection example.

I guess it was a mistake that you used two completely different domains for your two requests — i.e. you were trying to mask your real URL? If not, then that's why you're not getting any cookies. If were just trying to mask your URL, well that's why example.com exists. :)
Alternatively, and this is completely off the top of my head from code I wrote last week — it worked fine across multiple GETs, POSTs and subdomains:
DefaultHttpClient httpClient = new DefaultHttpClient();
CookieStore cookieJar = new BasicCookieStore();
httpClient.setCookieStore(cookieJar);
i.e. I'm explicitly using a DefaultHttpClient, which I believe has those extra get/setters for the cookie store. I don't think I used any context objects either.