title: What does "|=" mean? (pipe equal operator)
body: <p>I tried searching using Google Search and Stack&nbsp;Overflow, but it didn't show up any results. I have seen this in opensource library code:</p>
  
  <pre><code>Notification notification = new Notification(icon, tickerText, when);
  notification.defaults |= Notification.DEFAULT_SOUND;
  notification.defaults |= Notification.DEFAULT_VIBRATE;
  </code></pre>
  
  <p>What does "|=" ( <code>pipe equal operator</code> ) mean?</p>