code: public static LocalDate from(Calendar cal) {
          int year = cal.get(Calendar.YEAR);
          int month = cal.get(Calendar.MONTH)+1;
          int dayOfMonth = cal.get(Calendar.DAY_OF_MONTH);
          return new LocalDate(year, month, dayOfMonth);
      }
docs: Cerates a new instance from the given Calendar.
  @param cal the Calendar, not null.
  @return the corresponding LocalDate instance, never null.