question: @ SuppressWarnings ( "unchecked" ) public SortedSet < E > subSet ( E start , E end ) { return subSet ( start , true , end , false ) ; }
target:  Answers a SortedSet of the specified portion of this TreeSet which contains elements greater or equal to the start element but less than the end element. The returned SortedSet is backed by this TreeSet so changes to one are reflected by the other.