question: static String matchStringOrThrow ( Pattern p , ToDateParser params , Enum < ? > aEnum ) { String s = params . getInputStr ( ) ; Matcher matcher = p . matcher ( s ) ; if ( ! matcher . find ( ) ) { throwException ( params , format ( "Issue happened when parsing token '%s'" , aEnum . name ( ) ) ) ; } return matcher . group ( 1 ) ; }
target:  Match the pattern, or if not possible throw an exception.