LocalDateFormatter day of month cardinality

Question

Is there a format pattern for LocalDateFormatter to display the cardinality of the day of the month, as well as other values?

For example, I wish to print 2016 November First, or 2017 February Twenty-seventh.

Thanks in advance, Lucas

Answer 1

You can do this using DateTimeFormatterBuilder with the

public DateTimeFormatterBuilder appendText(TemporalField field, Map<Long, String> textLookup)

method that takes a Map which is used to look up the values for the field. Something like:

static final Map<Long, String> ORDINAL_DAYS = new HashMap<>();
static
{
  ORDINAL_DAYS.put(1, "First");
  ORDINAL_DAYS.put(2, "Second");
  ... values for month days 1 .. 31
  ORDINAL_DAYS.put(31, "Thirty-first");
}


DateTimeFormatter formatter = new DateTimeFormatterBuilder()
    .appendText(ChronoField.YEAR)
    .appendLiteral(' ')
    .appendText(ChronoField.MONTH_OF_YEAR)
    .appendLiteral(' ')
    .appendText(ChronoField.DAY_OF_MONTH, ORDINAL_DAYS)
    .toFormatter();

String formattedDate = formatter.format(date);