code: @GwtIncompatible("incompatible method")
      public static long getFragmentInMinutes(final Calendar calendar, final int fragment) {
          return getFragment(calendar, fragment, TimeUnit.MINUTES);
      }
docs: <p>Returns the number of minutes within the
  fragment. All datefields greater than the fragment will be ignored.</p>
  
  <p>Asking the minutes of any date will only return the number of minutes
  of the current hour (resulting in a number between 0 and 59). This
  method will retrieve the number of minutes for any fragment.
  For example, if you want to calculate the number of minutes past this month,
  your fragment is Calendar.MONTH. The result will be all minutes of the
  past day(s) and hour(s).</p>
  
  <p>Valid fragments are: Calendar.YEAR, Calendar.MONTH, both
  Calendar.DAY_OF_YEAR and Calendar.DATE, Calendar.HOUR_OF_DAY,
  Calendar.MINUTE, Calendar.SECOND and Calendar.MILLISECOND
  A fragment less than or equal to a MINUTE field will return 0.</p>
  
  <ul>
  <li>January 1, 2008 7:15:10.538 with Calendar.HOUR_OF_DAY as fragment will return 15
  (equivalent to calendar.get(Calendar.MINUTES))</li>
  <li>January 6, 2008 7:15:10.538 with Calendar.HOUR_OF_DAY as fragment will return 15
  (equivalent to calendar.get(Calendar.MINUTES))</li>
  <li>January 1, 2008 7:15:10.538 with Calendar.MONTH as fragment will return 15</li>
  <li>January 6, 2008 7:15:10.538 with Calendar.MONTH as fragment will return 435 (7*60 + 15)</li>
  <li>January 16, 2008 7:15:10.538 with Calendar.MILLISECOND as fragment will return 0
  (a millisecond cannot be split in minutes)</li>
  </ul>
  
  @param calendar the calendar to work with, not null
  @param fragment the {@code Calendar} field part of calendar to calculate
  @return number of minutes within the fragment of date
  @throws IllegalArgumentException if the date is <code>null</code> or
  fragment is not supported
  @since 2.4