java.util

Interface NavigableSet<E>

Type Parameters:

E - the type of element

All Superinterfaces:

Collection<E>, Iterable<E>, Set<E>, SortedSet<E>

All Known Implementing Classes:

TreeSet

public interface NavigableSet<E>
extends SortedSet<E>

NavigableSet is a SortedSet with navigation methods answering the closest matches for specified item.

Since:

1.6

Method Summary

Modifier and Type	Method and Description
E	ceiling(E e) Answers the smallest element bigger than or equal to the specified one, or null if no such element.
Iterator<E>	descendingIterator() Answers a descending iterator of this set.
NavigableSet<E>	descendingSet() Answers a reverse order view of this set.
E	floor(E e) Answers the biggest element less than or equal to the specified one, or null if no such element.
NavigableSet<E>	headSet(E end, boolean endInclusive) Answers a NavigableSet of the specified portion of this set which contains elements less than (or equal to, depends on endInclusive) the end element.
E	higher(E e) Answers the smallest element bigger than the specified one, or null if no such element.
E	lower(E e) Answers the biggest element less than the specified one, or null if no such element.
E	pollFirst() Deletes and answers the smallest element, or null if the set is empty.
E	pollLast() Deletes and answers the biggest element, or null if the set is empty.
NavigableSet<E>	subSet(E start, boolean startInclusive, E end, boolean endInclusive) Answers a NavigableSet of the specified portion of this set which contains elements greater (or equal to, depends on startInclusive) the start element but less than (or equal to, depends on endInclusive) the end element.
NavigableSet<E>	tailSet(E start, boolean startInclusive) Answers a NavigableSet of the specified portion of this set which contains elements greater (or equal to, depends on startInclusive) the start element.

Methods inherited from interface java.util.SortedSet

comparator, first, headSet, last, subSet, tailSet

Methods inherited from interface java.util.Set

add, addAll, clear, contains, containsAll, equals, hashCode, isEmpty, iterator, remove, removeAll, retainAll, size, toArray, toArray

Method Detail

pollFirst

E pollFirst()

Deletes and answers the smallest element, or null if the set is empty.

Returns:

the smallest element, or null if the set is empty

pollLast

E pollLast()

Deletes and answers the biggest element, or null if the set is empty.

Returns:

the biggest element, or null if the set is empty

higher

E higher(E e)

Answers the smallest element bigger than the specified one, or null if no such element.

Parameters:

e - the specified element

Returns:

the smallest element bigger than the specified one, or null if no such element

Throws:

ClassCastException - if the element cannot be compared with the ones in the set

NullPointerException - if the element is null and the set can not contain null

ceiling

E ceiling(E e)

Answers the smallest element bigger than or equal to the specified one, or null if no such element.

Parameters:

e - the specified element

Returns:

the smallest element bigger than or equal to the specified one, or null if no such element

Throws:

ClassCastException - if the element cannot be compared with the ones in the set

NullPointerException - if the element is null and the set can not contain null

lower

E lower(E e)

Answers the biggest element less than the specified one, or null if no such element.

Parameters:

e - the specified element

Returns:

the biggest element less than the specified one, or null if no such element

Throws:

ClassCastException - if the element cannot be compared with the ones in the set

NullPointerException - if the element is null and the set can not contain null

floor

E floor(E e)

Answers the biggest element less than or equal to the specified one, or null if no such element.

Parameters:

e - the specified element

Returns:

the biggest element less than or equal to the specified one, or null if no such element

Throws:

ClassCastException - if the element cannot be compared with the ones in the set

NullPointerException - if the element is null and the set can not contain null

descendingIterator

Iterator<E> descendingIterator()

Answers a descending iterator of this set.

Returns:

the descending iterator

descendingSet

NavigableSet<E> descendingSet()

Answers a reverse order view of this set.

Returns:

the reverse order view

subSet

NavigableSet<E> subSet(E start,
                       boolean startInclusive,
                       E end,
                       boolean endInclusive)

Answers a NavigableSet of the specified portion of this set which contains elements greater (or equal to, depends on startInclusive) the start element but less than (or equal to, depends on endInclusive) the end element. The returned NavigableSet is backed by this set so changes to one are reflected by the other.

Parameters:

start - the start element

startInclusive - true if the start element is in the returned set

end - the end element

endInclusive - true if the end element is in the returned set

Returns:

the subset

Throws:

ClassCastException - when the start or end object cannot be compared with the elements in this set

NullPointerException - when the start or end object is null and the set cannot contain null

IllegalArgumentException - when the start is bigger than end; or start or end is out of range and the set has a range

headSet

NavigableSet<E> headSet(E end,
                        boolean endInclusive)

Answers a NavigableSet of the specified portion of this set which contains elements less than (or equal to, depends on endInclusive) the end element. The returned NavigableSet is backed by this set so changes to one are reflected by the other.

Parameters:

end - the end element

endInclusive - true if the end element is in the returned set

Returns:

the subset

Throws:

ClassCastException - when the end object cannot be compared with the elements in this set

NullPointerException - when the end object is null and the set cannot contain handle null

IllegalArgumentException - when end is out of range and the set has a range

tailSet

NavigableSet<E> tailSet(E start,
                        boolean startInclusive)

Answers a NavigableSet of the specified portion of this set which contains elements greater (or equal to, depends on startInclusive) the start element. The returned NavigableSet is backed by this set so changes to one are reflected by the other.

Parameters:

start - the start element

startInclusive - true if the start element is in the returned set

Returns:

the subset

Throws:

ClassCastException - when the start object cannot be compared with the elements in this set

NullPointerException - when the start object is null and the set cannot contain null

IllegalArgumentException - when start is out of range and the set has a range