question: @ Nullable public Calendar detectDate ( String input ) { checkNotNull ( input ) ; Time . setTimeZone ( getTimeZone ( ) ) ; Options opt = new com . sk89q . jchronic . Options ( ) ; opt . setNow ( Calendar . getInstance ( getTimeZone ( ) ) ) ; Span date = Chronic . parse ( input , opt ) ; if ( date == null ) { return null ; } else { return date . getBeginCalendar ( ) ; } }
target:  Detect date from a user's input.