CSCM79.java

package main.servo;

import com.phidget22.*;

import java.io.IOException;

public class CSCM79 {

    private static final int SERVO_SERIAL_NUMBER = 19946;
    private static final int LCD_SERIAL_NUMBER = 39834;

    /*Variable for updating slider values, variable was
    made global to only update using getters and setters
    because slider keeps updating even on the same values every
    sec. Changes are only made if it's a new value. See getter
    and setter below
     */
    private static double voltageRatioNum = 0;

    public static void main(String[] args) {
        try {
            //Create the channels
            RCServo rcServo = new RCServo();
            LCD lcdScreen = new LCD();
            VoltageRatioInput slider = new VoltageRatioInput();

            //Setting address on channels
            rcServo.setDeviceSerialNumber(SERVO_SERIAL_NUMBER);
            lcdScreen.setDeviceSerialNumber(LCD_SERIAL_NUMBER);
            slider.setChannel(0);
            slider.setDeviceSerialNumber(LCD_SERIAL_NUMBER);

            //Attaching callbacks listeners to phidget objects when phidgets are connected
            rcServo.addAttachListener(attachEvent -> {
                try {
                    System.out.println("Server motor Device has been attached and device number is "
                            + attachEvent.getSource().getDeviceSerialNumber());
                } catch (PhidgetException e) {
                    e.printStackTrace();
                    System.out.println("Server motor Attach listener just threw an exception");
                }
            });
            lcdScreen.addAttachListener(attachEvent -> {
                try {
                    System.out.println("LCD Device has been attached and device number is "
                            + attachEvent.getSource().getDeviceSerialNumber());
                } catch (PhidgetException e) {
                    e.printStackTrace();
                    System.out.println("LCD Attach listener just threw an exception");
                }
            });
            slider.addAttachListener(attachEvent -> {
                try {
                    System.out.println("Slider Device has been attached and device number is "
                            + attachEvent.getSource().getDeviceSerialNumber());
                } catch (PhidgetException e) {
                    e.printStackTrace();
                    System.out.println("Slider Attach listener just threw an exception");
                }
            });

            //Opening the channel
            rcServo.open(5000);
            lcdScreen.open(5000);
            slider.open(5000);

            //Prepping LCD screen
            lcdScreen.setContrast(0.5);
            lcdScreen.setBacklight(0.5);
            lcdScreen.writeText(LCDFont.DIMENSIONS_5X8, 0, 0, "Starting Device");
            lcdScreen.flush();

            //Callback listeners for handling changes in event on phidgets
            rcServo.addPositionChangeListener(rcServoPositionChangeEvent -> {
                try {
                    lcdScreen.writeText(LCDFont.DIMENSIONS_6X12, 0, 0,
                            "" + rcServoPositionChangeEvent.getPosition());
                    lcdScreen.flush();
                    System.out.println("LCD triggered");
                } catch (PhidgetException e) {
                    e.printStackTrace();
                    System.out.println("RCServo threw an exception");
                }
            });
            slider.addVoltageRatioChangeListener(voltageRatioInputVoltageRatioChangeEvent -> {
                setVoltageRatioNum(voltageRatioInputVoltageRatioChangeEvent.getVoltageRatio());
                try {
                    /*RC servo default max rotation is 180 and slider is 1
                    scaling slider measurement to 180 by multiplying by 180
                     */
                    rcServo.setTargetPosition(getVoltageRatioNum() * 180);
                    rcServo.setEngaged(true);
                    System.out.println("RCServo position reported is " + getVoltageRatioNum() * 180);

                } catch (PhidgetException e) {
                    e.printStackTrace();
                    System.out.println("Slider threw an exception");
                }
            });


            //Open input stream to keep program running
            System.in.read();

            //Closing all Phidget connection to release resource
            rcServo.close();
            lcdScreen.close();
            slider.close();
        } catch (PhidgetException | IOException e) {
            e.printStackTrace();
        }
    }

    private static void setVoltageRatioNum(double regulator) {
        //Only set the value if input changes(reason stated above on variable declaration)
        if (voltageRatioNum != regulator) {
            voltageRatioNum = regulator;
        }
    }

    private static double getVoltageRatioNum() {
        return voltageRatioNum;
    }
}