My iPhone 4 decided to stop charging?

My IPhone Is less then a year old, the problem is NOT the charge cable, power outlet, or a case of having a dirty charge point. I would suspect my battery has failed me, but since the phone is still so new I would have to assume that cannot be the problem. The phone has died now, and will not accept charge when it was on or now that it is off. If anyone has any ideas then that would be helpful. Thanks.