title: Combining java.util.Dates to create a date-time
body: <p>I have current have two UI components used to specify a date and a time.  Both components return <code>java.util.Date</code> instances representing the calendar date and time respectively.  My question is:</p>
  
  <p>What is the best way to combine these values to create a <code>java.util.Date</code> instance representing the date and time?  <strong>I would like to avoid dependencies on Joda or other 3rd party libraries.</strong></p>
  
  <p>My current solution looks like this (but is there a better way?):</p>
  
  <pre><code>Date date = ... // Calendar date
  Date time = ... // Time
  
  Calendar calendarA = Calendar.getInstance();
  calendarA.setTime(date);
  
  Calendar calendarB = Calendar.getInstance();
  calendarB.setTime(time);
  
  calendarA.set(Calendar.HOUR_OF_DAY, calendarB.get(Calendar.HOUR_OF_DAY));
  calendarA.set(Calendar.MINUTE, calendarB.get(Calendar.MINUTE));
  calendarA.set(Calendar.SECOND, calendarB.get(Calendar.SECOND));
  calendarA.set(Calendar.MILLISECOND, calendarB.get(Calendar.MILLISECOND));
  
  Date result = calendarA.getTime();
  </code></pre>