Connect robot servo to RPi and use Java Embedded to program it (Part 5)

/*
 * Java Embedded Raspberry Pi Servo app
 */
package jerpiservo;

import java.io.FileWriter;
import java.io.File;

/**
 *
 * @author hinkmond
 */
public class ServoController {
    
    static final String GPIO_OUT = "out";
    static final String GPIO_ON = "1";
    static final String GPIO_OFF = "0";
    static String[] GpioChannels =  { "24" };

    /**
     * @param args the command line arguments
     */
    @SuppressWarnings("UseSpecificCatch")
    public static void main(String[] args) {
        FileWriter[] commandChannels;
        try {
            /*** Init GPIO port for output ***/
            // Open file handles to GPIO port unexport and export controls
            FileWriter unexportFile = 
                    new FileWriter("/sys/class/gpio/unexport");
            FileWriter exportFile = 
                    new FileWriter("/sys/class/gpio/export");

            // Loop through all ports if more than 1
            for (String gpioChannel : GpioChannels) {
                System.out.println(gpioChannel);
    
                // Reset the port, if needed
                File exportFileCheck = 
				new File("/sys/class/gpio/gpio"+gpioChannel);
                if (exportFileCheck.exists()) {
                    unexportFile.write(gpioChannel);
                    unexportFile.flush();
                }
                // Set the port for use
                exportFile.write(gpioChannel);   
                exportFile.flush();

                // Open file handle to port input/output control
                FileWriter directionFile =
                    new FileWriter("/sys/class/gpio/gpio" + gpioChannel + "/direction");
                // Set port for output
                directionFile.write(GPIO_OUT);
                directionFile.flush();
            }
            /*** Send commands to GPIO port ***/
            // Set up a GPIO port as a command channel
            FileWriter commandChannel = new 
			FileWriter("/sys/class/gpio/gpio" +
              	GpioChannels[0] + "/value");
            // Set initial variables for PWM
            int period = 20;
            int repeatLoop = 25;
            int counter;
            // Loop forever to create Pulse Width Modulation - PWM
            while (true) {
                /*--- Move servo clockwise to 90 degree position ---*/
                // Create a pulse for repeatLoop number of cycles
                for (counter=0; counter