Joystick not initialized Error

[GeeTwo]

These three are the most obvious issue:

Originally Posted by Technette

Description Resource Path Location Type
The type 'Joystick' must implement the inherited pure virtual method 'GenericHID::GetPOV' OI.cpp /GrabNGo/src line 30 Code Analysis Problem
The type 'Joystick' must implement the inherited pure virtual method 'GenericHID::GetRawAxis' OI.cpp /GrabNGo/src line 30 Code Analysis Problem
The type 'Joystick' must implement the inherited pure virtual method 'GenericHID::GetRawButton' OI.cpp /GrabNGo/src line 30 Code Analysis Problem

Joystick is a wpilib class, so it should inherit everything from GenericHID, with implementations.
From the opening paragraph in the javadoc for Joystick in WPIlibj (I'm assuming C/C++ is similar):

Handle input from standard Joysticks connected to the Driver Station. This class handles standard input that comes from the Driver Station. Each time a value is requested the most recent value is returned. There is a single class instance for each joystick and the mapping of ports to hardware buttons depends on the code in the driver station.

Three things I can think of to check:

1. Is Joystick in this context wpilib.Joystick, or something else?
2. Are you using a controller which does not match the description of the Joystick class?
3. Did you include configuration/code to map the joystick ports to hardware buttons in your Driver Station?