Compressor programming

#include “WPILib.h”
#include “Vision/AxisCamera.h”
#include “Vision/HSLImage.h”
#include “DriverStationLCD.h”
//#include “AxisCamera.h”
//#include “FrcError.h”
#include “Vision/PCVideoServer.h”
#include “Compressor.h”

class RobotDemo : public SimpleRobot
{

RobotDrive myRobot; // robot drive system
Joystick leftjoy;
Joystick rightjoy;
Joystick armjoy;
Jaguar arm;
Relay piston;
Relay compressor;
DigitalInput compressor_switch;
DigitalInput limitswitch_foward;
DigitalInput limitswitch_reverse;
Servo x_axis;
Servo y_axis;

myRobot(1, 2),
leftjoy(1),
rightjoy(2),
armjoy(3),
arm(3),
piston(4),
compressor(5),
compressor_switch(1),
limitswitch_foward(2),
limitswitch_reverse(3),
x_axis(10),
y_axis(9)
{
GetWatchdog().SetExpiration(1.00);
}
void OperatorControl(void)

compressor.Set(Relay::kOn);

Ok this is everything in my code that is relevant to the compressor can you please help me to understand why it is not turning? because i want to get a pressure switch to turn the compressor off when its at 115 but its not working, so when i manually set it to turn on using a button, it wont stop at 115 please help

Check out the Compressor class in WPILib. It takes a pressure switch and a relay as an input and automatically controls the air pressure.