import java.util.ArrayList; // Include this import at the beginning of your code

// Lets make some PVector objects with X and Y positions based on the object class
PVector vector1 = new PVector(10, 20);
PVector vector2 = new PVector(15, 30);
PVector vector3 = new PVector(20, 40);
PVector vector4 = new PVector(25, 50);
PVector vector5 = new PVector(30, 60);

// Now lets add them to a new arraylist
ArrayList<PVector> listOfPVectors = new ArrayList<PVector>();
listOfPVectors.add(vector1);
listOfPVectors.add(vector2);
listOfPVectors.add(vector3);
listOfPVectors.add(vector4);
listOfPVectors.add(vector5);

// Finally, now we have some objects in our list, lets iterate through all of them
for(int index = 0; index < listOfPVectors.size(); index ++) {
    PVector pvector = listOfPVectors.get(index);
    System.out.println(pvector.getXPosition());
    System.out.println(pvector.getYPosition());
}