code: public static void printTimeDifference(final Calendar pStartCalendar, final Calendar pEndCalendar, final PrintStream pPrintStream) {
  
      if (pPrintStream == null) {
        System.err.println(PRINTSTREAM_IS_NULL_ERROR_MESSAGE);
        return;
      }
      pPrintStream.println(buildTimeDifference(pStartCalendar, pEndCalendar));
    }
docs: Prints out the difference between to calendar times.
  The first calendar object is subtracted from the second one.
  <p>
  @param pStartCalendar the first {@code java.util.Calendar}.
  @param pEndCalendar the second {@code java.util.Calendar}.
  @param pPrintStream the {@code java.io.PrintStream} for flushing the results.
  @see <a href="http://java.sun.com/products/jdk/1.3/docs/api/java/util/Calendar.html">{@code java.util.Calendar}</a>