Make sure the provided URL is an instance of a String before doing the cast
HttpConn is not guaranteed to return a valid inputstream, so check for the special condition of null or empty stream
Separate the handling for 400- and 500-error codes
* For 400 errors we should probably chnage some parameters and resend the request
* For 500+ error codes we might only make the situation worse by resending requests
* Log the various cases, but no separate handling yet
Moved the base test class one level higher to make it more visible for other use with other unit test classes
Mark failed requests (400-505) as failed, and cancel the tasks depending on them
* Http-status constants in a separate class, rather than using framework classes or magic numbers
Improved handling of HTTP error codes
* Added constants for all the various HTTP methods and status codes
* Unit tests for basic cases of errors for the requests