I get travel confirmations that look like this:
"SQ 966 E 27JUL SINCGK"
= "Airline Space Flight Space BookingClass Space Date_with_Month_as_name Space 3LetterFrom 2LetterTo".
I can chop all this into pieces using a regex to submit it to a website. But the site would expect instead of 27JUL 27/07/2009 or at least 27/07. Is there a way to transform a regex result based on a piece in the input. Jan -> 01, Feb -> 02 ... Dec -> 12.
(Regex flavour is Java)
DateFormat is a more appropriate class:
DateFormat output = new SimpleDateFormat("dd/MM", Locale.US);
DateFormat input = new SimpleDateFormat("dd MMM", Locale.US);
System.out.println(output.format(input.parse("24 Dec")));
output:
24/12
It isnt a regex solution, but you could use SimpleDateFormat to help you with your final formatting. You should note in the JavaDoc that this is not a thread-safe option out of the box.
Alternatively, you could use DateFormatSymbols.getShortMonths() and iterate over the months to identify the index* and format your string manually.
*dont forget to add 1 ;)
edit:
I am not sure what you are looking for is possible in Java regex without the ablility to make code changes. The conditional constructs that Perl supports are not supported by Java because Java provides if-then-else support as a language feature.
I would be very careful with doing this with regular expressions as they don't tell you how the conversion went.
Extract every bit of information manually. Sanity check everything, and then use the SimpleDateFormat parser to get a Date object you can use from there on.
In Perl syntax (s{pattern}{replacement}):
s{([0-9][0-9])JAN}{\1/01}
s{([0-9][0-9])FEB}{\1/02}
s{([0-9][0-9])MAR}{\1/03}
s{([0-9][0-9])APR}{\1/04}
s{([0-9][0-9])MAY}{\1/05}
s{([0-9][0-9])JUN}{\1/06}
s{([0-9][0-9])JUL}{\1/07}
s{([0-9][0-9])AUG}{\1/08}
s{([0-9][0-9])SEP}{\1/09}
s{([0-9][0-9])OCT}{\1/10}
s{([0-9][0-9])NOV}{\1/11}
s{([0-9][0-9])DEC}{\1/12}
(Yes this is long and ugly, but it would probably work).