title: How implementation of java.util.queue uses LIFO?
body: <p>In Java doc: </p>
  
  <blockquote>
    <p>[...] Among the exceptions are priority queues, which order elements according to a supplied comparator, or the elements' natural ordering, and LIFO queues (or stacks) which order the elements LIFO (last-in-first-out)</p>
  </blockquote>
  
  <p>How implementation of <code>java.util.queue</code> uses <strong>LIFO</strong> instead of <strong>FIFO</strong>?</p>