Java Game Loop

///Public Java Game Loop

long lastTime = System.nanoTime();
double amountOfTicks = 60.0;
double ns = 1000000000 / amountOfTicks;
double delta = 0;
long timer = System.currentTimeMillis();
int frames = 0;
while (running) {
    long now = System.nanoTime();
    delta += (now - lastTime) / ns;
    lastTime = now;
    while (delta >= 1) {
        tick();
        delta--;
    }
    if (running) render();
    frames++;

    if (System.currentTimeMillis() - timer > 1000) {
        timer += 1000;
        System.out.println("FPS: "+frames);
        frames = 0;
    }
}
stop();