java.util · java.base · since Java 1.2

SortedSet

declaration

public interface SortedSet<E> extends Set<E>

A Set that maintains its elements in ascending order, by natural ordering or a supplied Comparator. Adds endpoint and range operations over Set.

Key methods

`E first() / E last()`	Lowest / highest element (throws if empty).
`SortedSet<E> headSet(E to) / tailSet(E from)`	Range views: strictly-below / at-or-above.
`SortedSet<E> subSet(E from, E to)`	Half-open [from, to) range view.
`Comparator<? super E> comparator()`	The ordering in use, or null for natural order.