title: Quickest way to clone a GregorianCalendar?
body: <p>I'm trying to make a deep copy of an object, including a <code>GregorianCalendar</code> instance. I'm always wary of using <code>clone()</code> and it doesn't seem to have been overridden here, so I'm just doing the copy field by field. Ideally, there'd be a copy constructor, which I could use like so:</p>
  
  <pre><code>GregorianCalendar newCalendar = new GregorianCalendar(oldCalendar);
  </code></pre>
  
  <p>Unfortunately I can't find any such functionality in the API and am stuck trying to figure out which fields I need to get an exact copy. So, to make a copy of one of these calendars, how would you do it? Am I missing some simple shortcut here?</p>