I have an ArrayList in Processing that I need to send to my Arduino, and have the Arduino store each element of this ArrayList in an array. Or, if I could send the ArrayList as a single entity to the Arduino, which would then store each of the ArrayList's elements into a corresponding position in an array, that would work as well. The main problem I'm having is that I don't know how I can tell what elements are in the Arduino's array, and Serial.println won't work because the Processing code is using the serial bus. Here's what I have:

Processing Code:

1. import processing.serial.*;
   
   //The serial port that the Arduino is on
   Serial port;
   //The ArrayList
   ArrayList ar;
   
   void setup() {
     size(200,200);
     //Initialize the serial port at 9600 baud
     port = new Serial(this, Serial.list()[0], 9600);
     //Set initial size of ArrayList ar
     ar = new ArrayList(10);
     //Add numbers 0-9 to ar
     for (int i=0; i<10; i++) {
       ar.add(i);
     }
   }
   
   void draw() {
     //Loop through each element of ar
     for (int i=0; i<ar.size(); i++) {
       //Print the current element out below
       println(ar.get(i));
       //Convert the object cast by ar into an integer
       int curInt = (Integer)ar.get(i);
       //Write that integer to port
       port.write(curInt);
     }