DateTimeFormatterBuilder#appendText(TemporalField, Map<Long,String>) throws exception when parsing

Question

I'm trying to parse text that represents a LocalDate value with the IsoField.QUARTER_OF_YEAR using a DateTimeFormatter returned by the DateTimeFormatterBuilder#buildFormatter() method.

The problematic text is "20 Oct 2018 Q2". The quarter value ("Q2") is admittedly incorrect for a conventional calendar year, here "2018". However, I am working with a fiscal year which ends on June 30, so that the date "20 Oct 2018" would be in the fiscal year's second quarter.

The formatter is built with the following code:

TemporalQuery<LocalDate> query = LocalDate::from;
String pattern = “d MMM uuuu qqq”;
Locale locale = Locale.forLanguageTag("en-US");
TemporalField tf = IsoFields.QUARTER_OF_YEAR;
Map<Long, String> m = new Hashtable<>();
m.put(4L, “Q2”);
DateTimeFormatter formatter = new DateTimeFormatterBuilder()                                                                                
                                       .parseCaseInsensitive()
                                       .appendPattern(pattern)
                                       .appendText(tf, m)
                                       .toFormatter(locale);
TemporalAccessor value = formatter.parse(text, query)

Attempts to parse generate a DateTimeParseException with the error message: “Text '20 Oct 2018 Q2' could not be parsed at index 0”

I’ve tried changing the order in which the parseCaseInsensitive() … appendText() methods are called. The exception is still thrown, although the specified index is 14 in one of the variations.

Possible reason for problem: The DateTimeFormatterBuilder#appendText(TemporalField, Map) method may work only in format operations, and not for parsing as here.

Thanks in advance for any ideas or help!

Answer 1

You try to parse the quarter year part twice - once per pattern instruction (using letter q) and once per builder-instruction (using method appendText). Solution: Remove the qqq-part in your pattern and use "d MMM uuuu ".

Some remarks however:

• Fiscal years are not supported at all.
• Use better HashMap instead of outdated Hashtable.
• The example code has special quotation marks instead of standard char (").
• The parsed value is equivalent to LocalDate.of(2018, 10, 20) (and has no information about your special quarters).