Greetings again;

Another question for another sketch.

This sketch is just a draft where the user can click to create a rectangle that then bounces around the screen. However, not only is my rectangle changing sizes but it is only bouncing off the top and left walls. Any advice?

1. Star[] stars = {
   };
   
   void setup() {
     size(600, 600);
     background(255);
   }
   
   void draw() {
     background(255);
     for (int i = 0; i < stars.length; i++) {
       stars[i].move();
       stars[i].display();
     }
   }
   
   void mouseClicked() {
     Star newStar = new Star(mouseX, mouseY);
     stars = (Star[]) append (stars, newStar);
   }
   
2. class Star {
     float x = 0;
     float y = 0;
     float speed = 1;
     int xdir = -1;
     int ydir = 1;
     int w = 10;
     int h = 10;
   
     Star(int x, int y) {
       this.x = x;
       this.y = y;
       this.speed = int(random(2, 10));
     }
       void move() {
         x += (xdir * speed);
         if (x < 0 || x > width ) {
           xdir = xdir * -1;
           x =+ (xdir * speed);
         }
         w=50*xdir;
         y+= (ydir * speed);
         if (y < 0|| y > height){
           ydir = ydir * -1;
           y =+ (ydir * speed);
         }
         h=50*ydir;
       }
   
       void display() {
         rect(x, y, x+50, y+50);
       }
     }
   

Thanks