Modify the generated code as follows:

• Add the following imports:

     import edu.wpi.first.wpilibj.Encoder;
     import edu.wpi.first.wpilibj.Talon;
  

• Declare variables for the Encoders and Motor controllers in the Robot class

     private Talon leftMotor, rightMotor;
     private Encoder leftEncoder, rightEncoder;
  

• In robotInit() instantiate the Encoder and Motor objects

     // Quadrature encoder has A and B channels connected to DIO0,1, DIO2,3
     leftEncoder = new Encoder(0, 1);
     rightEncoder = new Encoder(2, 3);
     // Peanut wheels are 7.5" in diameter
     // Encoders provide 1 count per degree of rotation
     leftEncoder.setDistancePerPulse((3.141592*7.5)/360);
     rightEncoder.setDistancePerPulse((3.141592*7.5)/360);
     // PWM motor controllers connected to PWM0, PWM1
     leftMotor = new Talon(0);
     rightMotor = new Talon(1);
  

• In robotPeriodic() display the encoder values:

    SmartDashboard.putNumber("Left", leftEncoder.getDistance());
    SmartDashboard.putNumber("Right", rightEncoder.getDistance());
  

• In autonomousInit() reset the encoder counts and start the motors:

    // Reset encoder counts to 0
    leftEncoder.reset();
    rightEncoder.reset();
    // start motors turning forward at 20% power
    leftMotor.set(0.20);
    // to go forward, left motor turns clockwise, right motor counter-clockwise
    rightMotor.set(-0.20);
  

• In the default section of autonomousPeriodic() stop if we've gone the desired distance. Notice our first use of the logical OR operator (||) to test whether either of two conditions is true

    if ((leftEncoder.getDistance() > 36.0) || 
        (rightEncoder.getDistance() > 36.0)) {
        leftMotor.stopMotor();
        rightMotor.stopMotor();
    }
  

For the complete Robot.java see here