java - extract date from string in Scala efficiently -

i want extract date (e.g. 2015-01-01) multiple strings have form in scala:

val s = "basedir/somedir/tmp/blah/2015-01-01.txt" 

i know can basic string split-trim-strip operations achieve that, there more cleaner way in scala? can use nice regex "hidden features" scala offers this?

i tried without success:

val s = "basedir/somedir/tmp/blah/2015-01-01.txt" val regex = "(\\d+)-(\\d+)-(\\d+).txt" val regex(year, month, date) = s 

use pattern matching using regex extractor

val regex = ".*/(\\d{4}-\\d{2}-\\d{2}).txt".r //remove / after .* if think not needed.  str match {   case regex(date) => some(date)   case _ => none } 

use above code instead of below because below 1 cause match error @ runtime.

val regex(a) = "basedir/somedir/tmp/blah/2015-01-01.txt" 

instead of .* in front of regex. can use unanchored.

val regex = "(\\d{4}-\\d{2}-\\d{2}).txt".r.unanchored 

scala repl

scala>  val regex = "(\\d{4}-\\d{2}-\\d{2}).txt".r.unanchored regex: scala.util.matching.unanchoredregex = (\d{4}-\d{2}-\d{2}).txt  scala> val regex(a) = "basedir/somedir/tmp/blah/2015-01-01.txt" a: string = 2015-01-01 

scala repl

scala> val regex = ".*/(\\d{4}-\\d{2}-\\d{2}).txt".r regex: scala.util.matching.regex = .*/(\d{4}-\d{2}-\d{2}).txt  scala> val regex(a) = "basedir/somedir/tmp/blah/2015-01-01.txt" a: string = 2015-01-01 

scala repl

scala> val str = "basedir/somedir/tmp/blah/2015-01-01.txt" str: string = basedir/somedir/tmp/blah/2015-01-01.txt  scala>  val regex = ".*/(\\d{4}-\\d{2}-\\d{2}).txt".r regex: scala.util.matching.regex = .*/(\d{4}-\d{2}-\d{2}).txt  scala>      |     str match {      |       case regex(date) => some(date)      |       case _ => none      |     } res21: option[string] = some(2015-01-01) 

if want match directory then

scala val regex = ".*/(.*)/(\\d{4}-\\d{2}-\\d{2}).txt".r regex: scala.util.matching.regex = .*/(.*)/(\d{4}-\d{2}-\d{2}).txt  scala> val s = "basedir/somedir/tmp/blah/2015-01-01.txt" s: string = "basedir/somedir/tmp/blah/2015-01-01.txt"  scala> val regex(dir, date) = s dir: string = "blah" date: string = "2015-01-01"