Hello I am trying to write a simple function which allows you to create Spline curve by clicking the mouse. I have some basics in OOP but I am new to processing. here is my source code (which doesn't work :( )

1. void setup()
   {
     size(300, 200);
     background(255);
     smooth();
   }
   
   void draw() {
     Lasso lasso1 = new Lasso();
     lasso1.createLasso();
   }
   
   class Lasso {
     ArrayList points;
    
     Lasso(){
       this.points = new ArrayList();
     }
    
     void createLasso(){
       noFill();
       stroke(0);
       beginShape();
       if(mousePressed && (mouseButton == LEFT))  {
         points.add(mouseX);
         points.add(mouseY);
         curveVertex(mouseX,mouseY);
   
       }
       if(mousePressed && (mouseButton == RIGHT)) {
         endShape();
     }
     }
   }

I also need to store the information about the spline, no matter how many times the user clicks (that's why I am using array list, but I'm affraid it only stores objects not primitives :( ) and of course RMB closes the spline :)
Has anyone some Idea how to make it work? I will be really grateful :)