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Android Volley error while posting data to server

here is the api response which works fine While posting data to the server I'm getting server volley error as response code but at the same time remaining API working fine.

HTTP 404 ordinary means "page not found" ...
host-name mydrivinglession.co.uk cannot even be resolved in DNS:
$ traceroute mydrivinglession.co.uk
mydrivinglession.co.uk: Name or service not known
... nor is it registered with co.uk
mydrivinglession.co.uk is available!
guess you would have to remove mydrivinglession.co.uk from your local hosts file... that most likely the only reason why the response, which you claim would be "working", appears to be "working".
one might want to establish a publicly available API, before attempting to perform requests... because your requests might run against a fantasy domain in the clouds, which nobody knows.

Call drive Rest API: 400 bad request

I am trying to use drive Rest API in my app by following the official quickstart documentation. I generated a SHA1 key, everything works fine but when I call drive API from android phone, I get 400 bad request.
How is this caused and how can I fix this?

HTTP 400 means that the server cannot or will not process the request due to an apparent client error (e.g., malformed request syntax, invalid request message framing, or deceptive request routing).
Could you please take a look at your HTTP request whether it is what you intended it to be?

HttpUrlConnection not working and shows different status code for GET and POST call

I am getting FileNotFoundException when making GET call to REST API. Here HTTP status code I get is 403.
For POST call I get IOException : No authentication challenges found, whereas I pass Authorization header. Here I get HTTP status code 401.
Look at my already asked question to see the code and logcat screen shot for POST call.
Below I am attaching logcat screen shot for GET call :
Note :
1) I have tried using Authenticator.
2) Tried different base64 flags such as NO_WRAP, URL_SAFE, DEFAULT.
3) My simple call to www.google.com works.
4) When I log urlConnection.getErrorStream(), last line in image is printed. I don't understand what is that and what does it mean. I have specified Content-type to application/json in header.
UPDATE : I tried using Burp and found that headers "Accept", "Content-type" were different. I used the same as in iOS app. But still it does not work.
Things to note :
1) It always throws an Exception on the line in = urlConnection.getInputStream();.
2) I logged few things and according to it, content-length is 114, which is not null. content-type is application/json; charser=utf-8.

There's a difference between your HTTP traffic for iOS and for Android. This is guaranteed, otherwise you'd get identical behaviour from the server. The difference is probably in HTTP header(s) &/or parameter(s).
This is very difficult to debug remotely via SO Q&A - E.g. we don't know what headers & parameters your iOS client is successfully using nor how your server is configured & programmed.
How to diagnose the problem & correct yourself:
Trace your working HTTP traffic: iOS client <-> server
Trace your non-working HTTP traffic: Android client <-> server
Compare (2) and (3). For the most thorough comparison, save each HTTP request and response message as a separate file for (2) and (3), then diff the corresponding files.
Recommended HTTP tracing tools:
Fiddler2 (windows only) See also Documentation
Burp (JVM-based: windows, linux, OSX, etc) See also Getting Started
WebScarab (JVM-based: windows, linux, OSX, etc) See also Getting Started
UPDATE
Seems you have the same problem for both GET and POST: the server is configured for BASIC authentication, but the client is not following the authentication protocol correctly. I think it just shows as a slightly different sympton in the two cases: for GET it says 'resource not found' (because you're not authenticated) and for POST the resource is given by you, but the server says you're not authorized to change the resource on the server. I suggest you've done enough (good!) debugging of request contents and now you should stop and focus on getting authentication working.
Send you GET/POST request to the server without Authorization header
Allow the server to prompt you for authentication with a 401 response with an WWW-Authenticate header containing a challenge string (e.g. WWW-Authenticate: Basic realm="Protected" see RFC 2617 HTTP Basic Authentication and Digest Authentication)
Now send an additional GET request to server that (either without/with the original request contents), but includes the Authentication header, with Base 64 encoded username:password (Authorization: Basic ZnJhbms6ZmllZGxlcg==)

I solved my problem and it is something I never tried to focus on while solving the problem.
I need not pass Authorization header. The thing is that there are 2 credentials come into the picture. one is server's authorization and second is credentials for login API. In my app, user creates an account and login to it. To authenticate the user I pass credentials to server and server authenticate it.
So when user enters correct credentials then response received is correct. And, in case of wrong credentials, my server passes a error message You are not authorized person, which I want to display to user(as in my iOS app). So the problem is here that HTTP status code (in case of wrong credentals) is 401 and that is why I don't receive the message sent by the server (and receive No authentication challenges found message).
The reason why I don't receive server message is that HttpUrlConnection don't give server response when HTTP status code is >= 400.
The only option to get error details in case status code 400 and above is to use getErrorStream() method and using that I was receiving No authentication challenges found message.
Finally, either I had to handle each status code, that is equal and above 400, at client side or I can use HttpClient, instead of HttpUrlConnection. And now I am moving to HttpClient.

I had a similar problem, and solved by passing the authenticated session cookie. Not sure if that is possible in your situation.

AuthUser="foobar"
AuthPass="password"
URL targetUrl = new URL("http://www.google.com/");
HttpURLConnection connection = (HttpURLConnection) targetUrl.openConnection();
connection.setRequestMethod("GET");
connection.setDoInput(true);
String authStr = Base64Variants.MIME_NO_LINEFEEDS.encode((AuthUser+":"+AuthPass).getBytes());
connection.addRequestProperty("Authorization", "Basic "+authStr);
InputStream inputStream= connection.getInputStream();
I just run something like this and it worked perfectly for me. Just make sure you use Base64Variants.MIME_NO_LINEFEEDS and you should be able to create a proper authentication header. If that doesn't work, then you might have some problem on the server side.

How to figure out if javax.servlet successfully sends the response

I'm using a jetty server to handle http requests. I would like to know if there is any way I can check if the response is successfully sent back to the client. Is there an error code or status that I can check, or an exception I can catch if the transfer to the client failed for any reason?
Thanks

Is there an error code or status that I can check, or an exception I can catch if the transfer to the client failed for any reason?
It sounds like you want the server to be able to know if the response was delivered completely to the client.
The simple answer is there isn't a way to know this. TCP/IP doesn't support this, HTTP does not support this, and the Servlet APIs don't support this.
In some circumstances, an exception may be throw if the server notices that the client has closed the connection early. But there are no guarantees that it will notice, or that it will result in an exception that will be visible to the application servlet code. Indeed it is quite likely that the close won't be noticed (if at all) until after the servlet call has returned.
If you want to implement some kind of "response delivered" acknowledgement for web pages, you could embed some "onload" Javascript in the webpage that sends an AJAX request back to the server. But then you have to consider the case where the user has disabled Javascript, or the original request was made by a non-browser application.

why this Https Post failed in Google App Engine

I'm simulating an HTTPS process with Google App Engine's URL fetch API. The process has 2 steps: first, a GET request will return an URL with URL-encoded session information and a cookie; and second, a POST with some payload to the returned URL.
I have used Firebug to capture the headers of the 2 requests, e.g User-agent, Keep-alive, Connection, Cookie. I used these same headers in my code (the cookie value is updated according to the response). Testing on my computer is successful but the code always fails at the POST step on Google's server. On my development box, the remote .NET app website replies to the POST request with a 200-OK with the information that I want, but on Google side, the remote .NET app website also give a 200-OK response but with a "Session timeout" message (which I don't want). So what have I missed?

Are you connectiong to the GAE applictation through appspot.com domain or a custom domain? SSL is supported only on appspot.com, so maybe this the reason?