public interface SortedMap<K, V>

ExtendsMap<K, V>

Known subtypesNavigableMap, TreeMap

A map that has its keys ordered. The sorting is according to either the natural ordering of its keys or the ordering given by a specified comparator.

Methods

public abstract Comparator<? super K> comparator()Returns the comparator used to compare keys in this sorted map.
public abstract K firstKey()Returns the first key in this sorted map.
public abstract SortedMap<K, V> headMap(K endKey)Returns a sorted map over a range of this sorted map with all keys that are less than the specified endKey.
public abstract K lastKey()Returns the last key in this sorted map.
public abstract SortedMap<K, V> subMap(K startKey, K endKey)Returns a sorted map over a range of this sorted map with all keys greater than or equal to the specified startKey and less than the specified endKey.
public abstract SortedMap<K, V> tailMap(K startKey)Returns a sorted map over a range of this sorted map with all keys that are greater than or equal to the specified startKey.

Inherited nested types

From Map

Map.Entry

Inherited methods

From Map

clear, containsKey, containsValue, entrySet, equals, get, hashCode, isEmpty, keySet, put, putAll, remove, size, values, getOrDefault, putIfAbsent, remove, replace, replace, forEach, replaceAll, computeIfAbsent, computeIfPresent, compute, merge

Method details

comparator

public abstract Comparator<? super K> comparator()
Returns the comparator used to compare keys in this sorted map.

Returns

the comparator or null if the natural order is used.

firstKey

public abstract K firstKey()
Returns the first key in this sorted map.

Returns

the first key in this sorted map.

Throws

NoSuchElementException
if this sorted map is empty.

headMap

public abstract SortedMap<K, V> headMap(K endKey)

Returns a sorted map over a range of this sorted map with all keys that are less than the specified endKey. Changes to the returned sorted map are reflected in this sorted map and vice versa.

Note: The returned map will not allow an insertion of a key outside the specified range.

Parameters

endKey K
the high boundary of the range specified.

Returns

a sorted map where the keys are less than endKey.

Throws

ClassCastException
if the class of the end key is inappropriate for this sorted map.
NullPointerException
if the end key is null and this sorted map does not support null keys.
IllegalArgumentException
if this map is itself a sorted map over a range of another map and the specified key is outside of its range.

lastKey

public abstract K lastKey()
Returns the last key in this sorted map.

Returns

the last key in this sorted map.

Throws

NoSuchElementException
if this sorted map is empty.

subMap

public abstract SortedMap<K, V> subMap(K startKey, K endKey)

Returns a sorted map over a range of this sorted map with all keys greater than or equal to the specified startKey and less than the specified endKey. Changes to the returned sorted map are reflected in this sorted map and vice versa.

Note: The returned map will not allow an insertion of a key outside the specified range.

Parameters

startKey K
the low boundary of the range (inclusive).
endKey K
the high boundary of the range (exclusive),

Returns

a sorted map with the key from the specified range.

Throws

ClassCastException
if the class of the start or end key is inappropriate for this sorted map.
NullPointerException
if the start or end key is null and this sorted map does not support null keys.
IllegalArgumentException
if the start key is greater than the end key, or if this map is itself a sorted map over a range of another sorted map and the specified range is outside of its range.

tailMap

public abstract SortedMap<K, V> tailMap(K startKey)

Returns a sorted map over a range of this sorted map with all keys that are greater than or equal to the specified startKey. Changes to the returned sorted map are reflected in this sorted map and vice versa.

Note: The returned map will not allow an insertion of a key outside the specified range.

Parameters

startKey K
the low boundary of the range specified.

Returns

a sorted map where the keys are greater or equal to startKey.

Throws

ClassCastException
if the class of the start key is inappropriate for this sorted map.
NullPointerException
if the start key is null and this sorted map does not support null keys.
IllegalArgumentException
if this map itself a sorted map over a range of another map and the specified key is outside of its range.