question: private DateTimeFormatter toFormatter ( Locale locale , ResolverStyle resolverStyle , Chronology chrono ) { Objects . requireNonNull ( locale , "locale" ) ; while ( active . parent != null ) { optionalEnd ( ) ; } CompositePrinterParser pp = new CompositePrinterParser ( printerParsers , false ) ; return new DateTimeFormatter ( pp , locale , DecimalStyle . STANDARD , resolverStyle , null , chrono , null ) ; }
target:  Completes this builder by creating the formatter.