arrays - Creating graphics objects that never overlap java -

i'm making small balloon game in java , trying write code, when create new 'balloon' objects don't overlap on screen.

the code have far is:

 public void newgame(){     ui.cleargraphics();     this.currentscore = 0;     this.totalpopped = 0;     (int = 0; < this.balloons.length-1; i++) {         this.balloons[i] = new balloon(50 + math.random()*400, 50 + math.random()*400);         (int j = + 1; j < this.balloons.length; j++) {             if (this.balloons[i] !=null && this.balloons[j] != null && this.balloons[i].istouching(balloons[j])) {                 this.balloons[j] = new balloon(50 + math.random()*400, 50+ math.random()*400);             }         }         this.balloons[i].draw();     }     ui.printmessage("new game: click on balloon.  high score = "+this.highscore); } 

using draw , istouching methods:

    public void draw(){     ui.setcolor(color);     ui.filloval(centerx-radius, centery-radius, radius*2, radius*2);     if (!this.popped){         ui.setcolor(color.black);         ui.drawoval(centerx-radius, centery-radius, radius*2, radius*2);     } }      /** returns true if balloon touching other balloon, , false otherwise  *  returns false if either balloon popped. */ public boolean istouching(balloon other){     if (this.popped || other.popped) return false;     double dx = other.centerx - this.centerx;     double dy = other.centery - this.centery;     double dist = other.radius + this.radius;     return (math.hypot(dx,dy) < dist); } 

how can write this, when balloons created, none of them touching each other?

right have 2 loops. in first loop balloons created. in second loop, every balloon tested against every other loop. test in first loop: after creating new balloon, test against existing balloons.