[SOLVED] PIC to PC communication and value storage

int analogDevice   = 0; //Device connected to pin AN0

void setup()
{
  Serial.begin(9600);  //Serial Comm start at 9600 baud                     
}
 
void loop()                     
{
 //Grab inputs
 int deviceReading = analogRead(analogDevice);  

 ///////////////PRINT TO CLI//////////////////////
 
 // print out the voltage
 Serial.print("\n");//Newline
 Serial.print(deviceReading); Serial.print(","); //Comma as delimiter

 delay(1000); //Print Rate
}

import processing.serial.*;
Serial mySerial;
String val;
int x = 0;
PrintWriter output;
void setup() {
   mySerial = new Serial( this, Serial.list()[0], 9600);
   output = createWriter( "data.txt" );
   output.println("INPUT PROTOTYPE"); //HEADER
}
void draw() {
    if (mySerial.available() > 0 ) {
         String value = mySerial.readStringUntil('\n'); //Read until new line
         if ( value != null ) {
              output.println( value );
            x++; 
         }
    }

}

void keyPressed() {
    output.flush();  // Writes the remaining data to the file
    output.close();  // Finishes the file
    exit();  // Stops the program
}