public void update() {
Sprite sprite;
// Iterate through sprite list
for (int cnt = 0; cnt < size(); cnt++) {
sprite = (Sprite) elementAt(cnt);
// Update a sprite's position
sprite.updatePosition();
// Test for collision. Positive
// result indicates a collision
int hitIndex = testForCollision(sprite);
if (hitIndex >= 0) {
// a collision has occurred
bounceOffSprite(cnt, hitIndex);
} // end if
} // end for loop
} // end update
