Multiple HTTP requests in one AsyncTask

Multiple HTTP requests in one AsyncTask

So I have an app that will first make a HTTPPOST request to validate login
details. If the login details are correct it should then further make
another two HTTPGET requests otherwise do nothing.
I know how to right the code to have this done with 3 AsyncTasks but is
there a way to do it from one ? Or is 3 seperate classes correct, coding
style wise ?
If not can someone point me in the right direction/give me an exampl of
how it would be done in one seeing as I have to evaluate the results of
the first HTTPPOST which I do in OnPostExecute and then have another
HTTPGET