title: How does AnimationTimer work?
body: <p>This is a quote from the <code>AnimationTimer</code> class documentation.</p>
  
  <blockquote>
    <p>The class AnimationTimer allows to create a timer, that is called in each frame while it is active. An extending class has to override the method handle(long) which will be called in every frame. The methods start() and stop() allow to start and stop the timer.</p>
  </blockquote>
  
  <p>But I don't know how many frames are rendered each second, and when the handle method  has been called ? before frame being rendered or after.</p>
  
  <p>And is it bad idea to use too many <code>AnimationTimer</code> in my application(Game)?</p>