java - How do I add more objects to the program? -

i have started taking java classes new , got task "bouncing balls". have make user input how many balls he/she wants see in screen. have tried doing loops sure have done wrong because keep seeing 1 ball. give me pointers/hints/ or indicate problem? thank :)

program:

public class bouncingball {      public static void main(string[] args) {          int n = stdin.readint();         for(int i=0;i<n;i++){         // set scale of coordinate system         stddraw.setxscale(-1.0, 1.0);         stddraw.setyscale(-1.0, 1.0);           // initial values             double rx = math.random();             double ry = math.random();    // position             double vx = 0.015, vy = 0.023;     // velocity             double radius = 0.05; // radius          // main animation loop         while (true)  {               // bounce off wall according law of elastic collision           //  (int = 0; < n; i++) {             if (math.abs(rx + vx) > 1.0 - radius) vx = -vx;             if (math.abs(ry + vy) > 1.0 - radius) vy = -vy;              // update position          //   (int = 0; < n; i++) {             rx = rx + vx;              ry = ry + vy;               // clear background             stddraw.clear(stddraw.gray);              // draw ball on screen           //  (int = 0; < n; i++) {             stddraw.setpencolor(stddraw.black);              stddraw.filledcircle(rx, ry, radius);               // display , pause 20 ms           //  (int = 0; < n; i++) {             stddraw.show(20);          }      }     }     }  

i assuming want n number of balls here. problem loop in line 3 spanning entire program, including animation loop. so, instead of spawning n balls, you're running game n-times each after other.