Convert an ordinal string to an integer with icu4j

Question

I am attempting to convert an ordinal string, say "FOURTH" to integer 4. How can I accomplish this with the International Components for Unicode library for Java, icu4j?

RuleBasedNumberFormat formatter = new RuleBasedNumberFormat(Locale.US, RuleBasedNumberFormat.ORDINAL);

return formatter.parse("FOURTH").intValue();

Seems like this is not working, as 0 is being returned. I'm expecting this to return 4.

Any help would be appreciated. Thank you.

You can use PluralRules. https://unicode-org.github.io/icu-docs/apidoc/released/icu4j/com/ibm/icu/text/PluralRules.html — , Apr 05 '23 at 15:10
For me, your code does not return `0`. It throws `java.text.ParseException: Unparseable number: "FOURTH"`. — andrewJames, Apr 05 '23 at 15:38
Interestingly, I found several existing questions that ask about integer to ordinal text, but this is the only Question I could find asking about the opposite, ordinal text to integer. — Basil Bourque, Apr 05 '23 at 19:10

score 3 · Accepted Answer · edited Apr 05 '23 at 19:22

So I read up on the Javadoc documentation of icu4j and the RuleBasedNumberFormat does not have FOURTH as a parsable string although it does support four. And instead of using RuleBasedNumberFormat.ORDINAL uses RuleBasedNumberFormat.SPELLOUT.

RuleBasedNumberFormat formatter = new RuleBasedNumberFormat( Locale.US , RuleBasedNumberFormat.SPELLOUT );
try
{
    int result = formatter.parse( "FOURTH".toLowerCase( Locale.ROOT ) ).intValue();
    System.out.println( "result = " + result );
}
catch ( ParseException e )
{
    … add code to handle exception.
}

When run:

4

This is what the code should look like and make sure to use .toLowerCase(Locale.ROOT) because parse does not work on upperCase strings.

Nice! A word of warning: This works for `THIRTY-THIRD` - but for `THIRTYTHIRD`, it incorrectly returns `30` (with no errors). So, this relies on hyphenation (and spelling, of course). — andrewJames, Apr 05 '23 at 18:02

Convert an ordinal string to an integer with icu4j

1 Answers1