Worked for me -  use the . operator after the object name to access any of the class attributes see here

1. Deflector mouseDeflector;
2. void setup() {
3.   size(500, 500);
4.   mouseDeflector = new Deflector(0.01);
5.   println(mouseDeflector.rotRate);
6.   println(mouseDeflector.lenX);
7. }
8. 
   
9. void mousePressed() {
10.   mouseDeflector.mousePressed();
11. }
12. 
    
13. void mouseReleased() {
14.   mouseDeflector.mouseReleased();
15. }
16. 
    
17. void draw() {
18.   background (128);
19.   mouseDeflector.draw();
20. }

Thanks! Didn't know it was that simple.. I assumed the . operator only worked for functions.

In short, you need operator . to access anything outside a class and/or isn't inherited.
Take notice though that a Processing sketch itself is a disguised parent class which extends PApplet!