question: public static ServerSideSortRequestControl newControl ( final boolean isCritical , final Collection < SortKey > keys ) { Reject . ifNull ( keys ) ; Reject . ifFalse ( ! keys . isEmpty ( ) , "keys must not be empty" ) ; return new ServerSideSortRequestControl ( isCritical , Collections . unmodifiableList ( new ArrayList < SortKey > ( keys ) ) ) ; }
target:  Creates a new server side sort request control with the provided criticality and list of sort keys.