title: Java - Future.get() multiple invocations
body: <p>How does Java's <code>Future.get()</code> behave in the case where it is called multiple times after the task is completed?
  Does it return the the same result? Or does throw an <code>ExecutionException</code> again and again with the same exception if the computation failed?
  I can not find anything in the docs about it!</p>