My Android App does http posts to URLs like http://example.com/abc.php?email=abc@xyz.com So the Android App basically talks to PHPs on the server side and receives JSON response
As Kaj said in the comment, one option is to catch the exception, and perhaps retry or post a failure message.
For response codes != 200, just read them an do your job inside an if (con.getResponseCode() == 200)
block
Another alternative option, is to use the much nicer Apache classes:
http://developer.android.com/reference/org/apache/http/package-summary.html
For a snippet, check BalusC's tutorial here in SO: Using java.net.URLConnection to fire and handle HTTP requests