code: public Shape createBullet(int x, int y, int diameter) {
          return createEllipseInternal(x, y, diameter, diameter);
      }
docs: Return a path for a simple bullet.
  
  @param  x        the X coordinate of the upper-left corner of the bullet
  @param  y        the Y coordinate of the upper-left corner of the bullet
  @param  diameter the diameter of the bullet
  
  @return a path representing the shape.