Hit the rectangle and make a counter

Hamzeh_89

please i am very beginner of using processing , my question is how to make the balls hit the rectangle ? and make counter for the balls that hit it i will be very thankful for your help

here is the code

int totalDots = 80;
Dot[] dots = new Dot[totalDots];

int width, height;
color fillColor;
float diameter = 12.0;
 float rectSize = 100;

void setup() {
    // initialization
    width = 480;
    height = 400;
    size(480, 400);
    // initial fill colour
    fillColor = color(255, 0, 0);
    fill(fillColor);
    noStroke();
    // array of dots
    for (int i = 0; i < totalDots; i++) {
        Dot d = new Dot();
        d.x = random(width);
        d.y = random(height);
        d.vx = random(2.0) - 1.0;
        d.vy = random(2.0) - 1.0;
        dots[i] = d;
    }
    background(0);
};

void draw() {
    fill(0, 70);
    rect(0, 0, width, height);

    float r = 255;
    float g = 255;
    float b = 255;

    for (int i = 0; i < totalDots; i++) {
        r = map(dots[i].x, 0, width, 0, 255);
        g = map(dots[i].y, 0, height, 0, 255);
        fill(r, g, b);
        dots[i].update();
        ellipse(dots[i].x, dots[i].y, diameter, diameter);

        { rect(0, 0, 0, height);
      rect(width-10, mouseY-rectSize/2, 10, rectSize);

        }


    }
};

class Dot {
    float x = 0.0;
    float y = 0.0;
    float vx = 0.0;
    float vy = 0.0;

    void update(){
      // update the velocity
      this.vx += random(2.0) - 1.0;
      this.vx *= .96;
      this.vy += random(2.0) - 1.0;
      this.vy *= .96;
      // update the position
      this.x += this.vx;
      this.y += this.vy;
      // handle boundary collision
      if (this.x > width) { this.x = width; this.vx *= -1.0; }
      if (this.x < 0) { this.x = 0; this.vx *= -1.0; }
      if (this.y > height) { this.y = height; this.vy *= -1.0; }
      if (this.y < 0) { this.y = 0; this.vy *= -1.0; }
    }
}

jeremydouglass

Please do not post duplicates on this forum. This is a continuation of

https://forum.processing.org/two/discussion/25073/counting-the-balls-that-hit-the-rectangle

so continue posting updates and closely related questions there.