Last year, we used a "Bang Bang" controller, which Mr. Ether helped us implement (though he got the idea from another member here, IIRC) for controlling our shooter wheel.
My C++ (similar enough to Java to help) source code from last year lives here:
https://github.com/TeamExcel/Project.../Robot2012.cpp
Lines 1063 and 1346 are most interesting for you.
The basic proposition is that a PID controller is overkill, or the wrong tool for the job; when you power the wheel, the RPM will increase, when you don't power the wheel, the RPM will decrease. Since you have direct control over what you want to change (speed of the wheel), you simply apply power when the wheel isn't going fast enough, and remove power once it is going fast enough; it won't continue going faster when you remove power, so you don't have to reduce power as you approach the setpoint (one of the features of a PID), and once you pass your setpoint removing power is the best way to reduce your speed (rather than applying power in the negative direction).
Our output to the motor uses a voltage ramp to prevent any big snap on/off actions (ie if the motor is off, quickly ramp up the voltage toward 100%, rather than jumping there instantly), other than that, it's "On" when too slow, and "Off" when too fast.
Make sure you are not in "brake" mode on your motor controller (a jumper on the Jaguar controls this).