K
- the type of keys maintained by this mapV
- the type of mapped valuesSerializable
, Cloneable
, ConcurrentMap<K,V>
, ConcurrentNavigableMap<K,V>
, Map<K,V>
, NavigableMap<K,V>
, SequencedMap<K,V>
, SortedMap<K,V>
public class ConcurrentSkipListMap<K,V> extends AbstractMap<K,V> implements ConcurrentNavigableMap<K,V>, Cloneable, Serializable
ConcurrentNavigableMap
implementation. The map is sorted according to the natural ordering of its keys, or by a Comparator
provided at map creation time, depending on which constructor is used. This class implements a concurrent variant of SkipLists providing expected average log(n) time cost for the containsKey
, get
, put
and remove
operations and their variants. Insertion, removal, update, and access operations safely execute concurrently by multiple threads.
Iterators and spliterators are weakly consistent.
Ascending key ordered views and their iterators are faster than descending ones.
All Map.Entry
pairs returned by methods in this class and its views represent snapshots of mappings at the time they were produced. They do not support the Entry.setValue
method. (Note however that it is possible to change mappings in the associated map using put
, putIfAbsent
, or replace
, depending on exactly which effect you need.)
Beware that bulk operations putAll
, equals
, toArray
, containsValue
, and clear
are not guaranteed to be performed atomically. For example, an iterator operating concurrently with a putAll
operation might view only some of the added elements.
This class and its views and iterators implement all of the optional methods of the Map
and Iterator
interfaces. Like most other concurrent collections, this class does not permit the use of null
keys or values because some null return values cannot be reliably distinguished from the absence of elements.
This class is a member of the Java Collections Framework.
AbstractMap.SimpleEntry<K,V>, AbstractMap.SimpleImmutableEntry<K,V>
Constructor | Description |
---|---|
ConcurrentSkipListMap() |
Constructs a new, empty map, sorted according to the natural ordering of the keys. |
ConcurrentSkipListMap |
Constructs a new, empty map, sorted according to the specified comparator. |
ConcurrentSkipListMap |
Constructs a new map containing the same mappings as the given map, sorted according to the natural ordering of the keys. |
ConcurrentSkipListMap |
Constructs a new map containing the same mappings and using the same ordering as the specified sorted map. |
Modifier and Type | Method | Description |
---|---|---|
Map.Entry |
ceilingEntry |
Returns a key-value mapping associated with the least key greater than or equal to the given key, or null if there is no such entry. |
K |
ceilingKey |
Returns the least key greater than or equal to the given key, or null if there is no such key. |
void |
clear() |
Removes all of the mappings from this map. |
ConcurrentSkipListMap |
clone() |
Returns a shallow copy of this ConcurrentSkipListMap instance. |
Comparator |
comparator() |
Returns the comparator used to order the keys in this map, or null if this map uses the natural ordering of its keys. |
V |
compute |
Attempts to compute a mapping for the specified key and its current mapped value (or null if there is no current mapping). |
V |
computeIfAbsent |
If the specified key is not already associated with a value, attempts to compute its value using the given mapping function and enters it into this map unless null . |
V |
computeIfPresent |
If the value for the specified key is present, attempts to compute a new mapping given the key and its current mapped value. |
boolean |
containsKey |
Returns true if this map contains a mapping for the specified key. |
boolean |
containsValue |
Returns true if this map maps one or more keys to the specified value. |
NavigableSet |
descendingKeySet() |
Returns a reverse order NavigableSet view of the keys contained in this map. |
ConcurrentNavigableMap |
descendingMap() |
Returns a reverse order view of the mappings contained in this map. |
Set |
entrySet() |
Returns a Set view of the mappings contained in this map. |
boolean |
equals |
Compares the specified object with this map for equality. |
Map.Entry |
firstEntry() |
Returns a key-value mapping associated with the least key in this map, or null if the map is empty. |
K |
firstKey() |
Returns the first (lowest) key currently in this map. |
Map.Entry |
floorEntry |
Returns a key-value mapping associated with the greatest key less than or equal to the given key, or null if there is no such key. |
K |
floorKey |
Returns the greatest key less than or equal to the given key, or null if there is no such key. |
V |
get |
Returns the value to which the specified key is mapped, or null if this map contains no mapping for the key. |
V |
getOrDefault |
Returns the value to which the specified key is mapped, or the given defaultValue if this map contains no mapping for the key. |
ConcurrentNavigableMap |
headMap |
Returns a view of the portion of this map whose keys are strictly less than toKey . |
ConcurrentNavigableMap |
headMap |
Returns a view of the portion of this map whose keys are less than (or equal to, if inclusive is true) toKey . |
Map.Entry |
higherEntry |
Returns a key-value mapping associated with the least key strictly greater than the given key, or null if there is no such key. |
K |
higherKey |
Returns the least key strictly greater than the given key, or null if there is no such key. |
boolean |
isEmpty() |
Returns true if this map contains no key-value mappings. |
NavigableSet |
keySet() |
Returns a NavigableSet view of the keys contained in this map. |
Map.Entry |
lastEntry() |
Returns a key-value mapping associated with the greatest key in this map, or null if the map is empty. |
K |
lastKey() |
Returns the last (highest) key currently in this map. |
Map.Entry |
lowerEntry |
Returns a key-value mapping associated with the greatest key strictly less than the given key, or null if there is no such key. |
K |
lowerKey |
Returns the greatest key strictly less than the given key, or null if there is no such key. |
V |
merge |
If the specified key is not already associated with a value, associates it with the given value. |
NavigableSet |
navigableKeySet() |
Returns a NavigableSet view of the keys contained in this map. |
Map.Entry |
pollFirstEntry() |
Removes and returns a key-value mapping associated with the least key in this map, or null if the map is empty. |
Map.Entry |
pollLastEntry() |
Removes and returns a key-value mapping associated with the greatest key in this map, or null if the map is empty. |
V |
put |
Associates the specified value with the specified key in this map. |
V |
putFirst |
Throws UnsupportedOperationException . |
V |
putIfAbsent |
If the specified key is not already associated with a value, associates it with the given value. |
V |
putLast |
Throws UnsupportedOperationException . |
V |
remove |
Removes the mapping for the specified key from this map if present. |
boolean |
remove |
Removes the entry for a key only if currently mapped to a given value. |
V |
replace |
Replaces the entry for a key only if currently mapped to some value. |
boolean |
replace |
Replaces the entry for a key only if currently mapped to a given value. |
int |
size() |
Returns the number of key-value mappings in this map. |
ConcurrentNavigableMap |
subMap |
Returns a view of the portion of this map whose keys range from fromKey to toKey . |
ConcurrentNavigableMap |
subMap |
Returns a view of the portion of this map whose keys range from fromKey , inclusive, to toKey , exclusive. |
ConcurrentNavigableMap |
tailMap |
Returns a view of the portion of this map whose keys are greater than or equal to fromKey . |
ConcurrentNavigableMap |
tailMap |
Returns a view of the portion of this map whose keys are greater than (or equal to, if inclusive is true) fromKey . |
Collection |
values() |
Returns a Collection view of the values contained in this map. |
forEach, replaceAll
reversed
sequencedEntrySet, sequencedKeySet, sequencedValues
public ConcurrentSkipListMap()
public ConcurrentSkipListMap(Comparator<? super K> comparator)
comparator
- the comparator that will be used to order this map. If null
, the natural ordering of the keys will be used.public ConcurrentSkipListMap(Map<? extends K,? extends V> m)
m
- the map whose mappings are to be placed in this mapClassCastException
- if the keys in m
are not Comparable
, or are not mutually comparableNullPointerException
- if the specified map or any of its keys or values are nullpublic ConcurrentSkipListMap(SortedMap<K,? extends V> m)
m
- the sorted map whose mappings are to be placed in this map, and whose comparator is to be used to sort this mapNullPointerException
- if the specified sorted map or any of its keys or values are nullpublic ConcurrentSkipListMap<K,V> clone()
ConcurrentSkipListMap
instance. (The keys and values themselves are not cloned.)clone
in class AbstractMap<K,V>
public boolean containsKey(Object key)
true
if this map contains a mapping for the specified key.containsKey
in interface Map<K,V>
containsKey
in class AbstractMap<K,V>
key
- key whose presence in this map is to be testedtrue
if this map contains a mapping for the specified keyClassCastException
- if the specified key cannot be compared with the keys currently in the mapNullPointerException
- if the specified key is nullpublic V get(Object key)
null
if this map contains no mapping for the key. More formally, if this map contains a mapping from a key k
to a value v
such that key
compares equal to k
according to the map's ordering, then this method returns v
; otherwise it returns null
. (There can be at most one such mapping.)
get
in interface Map<K,V>
get
in class AbstractMap<K,V>
key
- the key whose associated value is to be returnednull
if this map contains no mapping for the keyClassCastException
- if the specified key cannot be compared with the keys currently in the mapNullPointerException
- if the specified key is nullpublic V getOrDefault(Object key, V defaultValue)
getOrDefault
in interface ConcurrentMap<K,V>
getOrDefault
in interface Map<K,V>
key
- the keydefaultValue
- the value to return if this map contains no mapping for the given keyNullPointerException
- if the specified key is nullpublic V put(K key, V value)
put
in interface Map<K,V>
put
in class AbstractMap<K,V>
key
- key with which the specified value is to be associatedvalue
- value to be associated with the specified keynull
if there was no mapping for the keyClassCastException
- if the specified key cannot be compared with the keys currently in the mapNullPointerException
- if the specified key or value is nullpublic V remove(Object key)
remove
in interface Map<K,V>
remove
in class AbstractMap<K,V>
key
- key for which mapping should be removednull
if there was no mapping for the keyClassCastException
- if the specified key cannot be compared with the keys currently in the mapNullPointerException
- if the specified key is nullpublic boolean containsValue(Object value)
true
if this map maps one or more keys to the specified value. This operation requires time linear in the map size. Additionally, it is possible for the map to change during execution of this method, in which case the returned result may be inaccurate.containsValue
in interface Map<K,V>
containsValue
in class AbstractMap<K,V>
value
- value whose presence in this map is to be testedtrue
if a mapping to value
exists; false
otherwiseNullPointerException
- if the specified value is nullpublic int size()
Integer.MAX_VALUE
elements, returns Integer.MAX_VALUE
.public boolean isEmpty()
true
if this map contains no key-value mappings.public void clear()
public V computeIfAbsent(K key, Function<? super K,? extends V> mappingFunction)
null
. The function is NOT guaranteed to be applied once atomically only if the value is not present.computeIfAbsent
in interface ConcurrentMap<K,V>
computeIfAbsent
in interface Map<K,V>
key
- key with which the specified value is to be associatedmappingFunction
- the function to compute a valueNullPointerException
- if the specified key is null or the mappingFunction is nullpublic V computeIfPresent(K key, BiFunction<? super K,? super V,? extends V> remappingFunction)
computeIfPresent
in interface ConcurrentMap<K,V>
computeIfPresent
in interface Map<K,V>
key
- key with which a value may be associatedremappingFunction
- the function to compute a valueNullPointerException
- if the specified key is null or the remappingFunction is nullpublic V compute(K key, BiFunction<? super K,? super V,? extends V> remappingFunction)
null
if there is no current mapping). The function is NOT guaranteed to be applied once atomically.compute
in interface ConcurrentMap<K,V>
compute
in interface Map<K,V>
key
- key with which the specified value is to be associatedremappingFunction
- the function to compute a valueNullPointerException
- if the specified key is null or the remappingFunction is nullpublic V merge(K key, V value, BiFunction<? super V,? super V,? extends V> remappingFunction)
null
. The function is NOT guaranteed to be applied once atomically.merge
in interface ConcurrentMap<K,V>
merge
in interface Map<K,V>
key
- key with which the specified value is to be associatedvalue
- the value to use if absentremappingFunction
- the function to recompute a value if presentNullPointerException
- if the specified key or value is null or the remappingFunction is nullpublic NavigableSet<K> keySet()
NavigableSet
view of the keys contained in this map. The set's iterator returns the keys in ascending order. The set's spliterator additionally reports Spliterator.CONCURRENT
, Spliterator.NONNULL
, Spliterator.SORTED
and Spliterator.ORDERED
, with an encounter order that is ascending key order.
The spliterator's comparator is null
if the map's comparator is null
. Otherwise, the spliterator's comparator is the same as or imposes the same total ordering as the map's comparator.
The set is backed by the map, so changes to the map are reflected in the set, and vice-versa. The set supports element removal, which removes the corresponding mapping from the map, via the Iterator.remove
, Set.remove
, removeAll
, retainAll
, and clear
operations. It does not support the add
or addAll
operations.
The view's iterators and spliterators are weakly consistent.
This method is equivalent to method navigableKeySet
.
public Collection<V> values()
Collection
view of the values contained in this map. The collection's iterator returns the values in ascending order of the corresponding keys. The collections's spliterator additionally reports Spliterator.CONCURRENT
, Spliterator.NONNULL
and Spliterator.ORDERED
, with an encounter order that is ascending order of the corresponding keys.
The collection is backed by the map, so changes to the map are reflected in the collection, and vice-versa. The collection supports element removal, which removes the corresponding mapping from the map, via the Iterator.remove
, Collection.remove
, removeAll
, retainAll
and clear
operations. It does not support the add
or addAll
operations.
The view's iterators and spliterators are weakly consistent.
public Set<Map.Entry<K,V>> entrySet()
Set
view of the mappings contained in this map. The set's iterator returns the entries in ascending key order. The set's spliterator additionally reports Spliterator.CONCURRENT
, Spliterator.NONNULL
, Spliterator.SORTED
and Spliterator.ORDERED
, with an encounter order that is ascending key order.
The set is backed by the map, so changes to the map are reflected in the set, and vice-versa. The set supports element removal, which removes the corresponding mapping from the map, via the Iterator.remove
, Set.remove
, removeAll
, retainAll
and clear
operations. It does not support the add
or addAll
operations.
The view's iterators and spliterators are weakly consistent.
The Map.Entry
elements traversed by the iterator
or spliterator
do not support the setValue
operation.
public ConcurrentNavigableMap<K,V> descendingMap()
ConcurrentNavigableMap
The returned map has an ordering equivalent to Collections.reverseOrder
(comparator())
. The expression m.descendingMap().descendingMap()
returns a view of m
essentially equivalent to m
.
descendingMap
in interface ConcurrentNavigableMap<K,V>
descendingMap
in interface NavigableMap<K,V>
public NavigableSet<K> descendingKeySet()
ConcurrentNavigableMap
NavigableSet
view of the keys contained in this map. The set's iterator returns the keys in descending order. The set is backed by the map, so changes to the map are reflected in the set, and vice-versa. The set supports element removal, which removes the corresponding mapping from the map, via the Iterator.remove
, Set.remove
, removeAll
, retainAll
, and clear
operations. It does not support the add
or addAll
operations. The view's iterators and spliterators are weakly consistent.
descendingKeySet
in interface ConcurrentNavigableMap<K,V>
descendingKeySet
in interface NavigableMap<K,V>
public boolean equals(Object o)
true
if the given object is also a map and the two maps represent the same mappings. More formally, two maps m1
and m2
represent the same mappings if m1.entrySet().equals(m2.entrySet())
. This operation may return misleading results if either map is concurrently modified during execution of this method.public V putIfAbsent(K key, V value)
map
:
if (!map.containsKey(key))
return map.put(key, value);
else
return map.get(key);
except that the action is performed atomically.putIfAbsent
in interface ConcurrentMap<K,V>
putIfAbsent
in interface Map<K,V>
key
- key with which the specified value is to be associatedvalue
- value to be associated with the specified keynull
if there was no mapping for the keyClassCastException
- if the specified key cannot be compared with the keys currently in the mapNullPointerException
- if the specified key or value is nullpublic boolean remove(Object key, Object value)
map
:
if (map.containsKey(key)
&& Objects.equals(map.get(key), value)) {
map.remove(key);
return true;
} else {
return false;
}
except that the action is performed atomically.remove
in interface ConcurrentMap<K,V>
remove
in interface Map<K,V>
key
- key with which the specified value is associatedvalue
- value expected to be associated with the specified keytrue
if the value was removedClassCastException
- if the specified key cannot be compared with the keys currently in the mapNullPointerException
- if the specified key is nullpublic boolean replace(K key, V oldValue, V newValue)
map
:
if (map.containsKey(key)
&& Objects.equals(map.get(key), oldValue)) {
map.put(key, newValue);
return true;
} else {
return false;
}
except that the action is performed atomically.replace
in interface ConcurrentMap<K,V>
replace
in interface Map<K,V>
key
- key with which the specified value is associatedoldValue
- value expected to be associated with the specified keynewValue
- value to be associated with the specified keytrue
if the value was replacedClassCastException
- if the specified key cannot be compared with the keys currently in the mapNullPointerException
- if any of the arguments are nullpublic V replace(K key, V value)
map
:
if (map.containsKey(key))
return map.put(key, value);
else
return null;
except that the action is performed atomically.replace
in interface ConcurrentMap<K,V>
replace
in interface Map<K,V>
key
- key with which the specified value is associatedvalue
- value to be associated with the specified keynull
if there was no mapping for the keyClassCastException
- if the specified key cannot be compared with the keys currently in the mapNullPointerException
- if the specified key or value is nullpublic Comparator<? super K> comparator()
SortedMap
null
if this map uses the natural ordering of its keys.comparator
in interface SortedMap<K,V>
null
if this map uses the natural ordering of its keyspublic K firstKey()
SortedMap
firstKey
in interface SortedMap<K,V>
NoSuchElementException
- if this map is emptypublic K lastKey()
SortedMap
lastKey
in interface SortedMap<K,V>
NoSuchElementException
- if this map is emptypublic V putFirst(K k, V v)
UnsupportedOperationException
. The encounter order induced by this map's comparison method determines the position of mappings, so explicit positioning is not supported.putFirst
in interface SequencedMap<K,V>
putFirst
in interface SortedMap<K,V>
k
- the keyv
- the valueUnsupportedOperationException
- alwayspublic V putLast(K k, V v)
UnsupportedOperationException
. The encounter order induced by this map's comparison method determines the position of mappings, so explicit positioning is not supported.putLast
in interface SequencedMap<K,V>
putLast
in interface SortedMap<K,V>
k
- the keyv
- the valueUnsupportedOperationException
- alwayspublic ConcurrentNavigableMap<K,V> subMap(K fromKey, boolean fromInclusive, K toKey, boolean toInclusive)
NavigableMap
fromKey
to toKey
. If fromKey
and toKey
are equal, the returned map is empty unless fromInclusive
and toInclusive
are both true. The returned map is backed by this map, so changes in the returned map are reflected in this map, and vice-versa. The returned map supports all optional map operations that this map supports. The returned map will throw an IllegalArgumentException
on an attempt to insert a key outside of its range, or to construct a submap either of whose endpoints lie outside its range.
subMap
in interface ConcurrentNavigableMap<K,V>
subMap
in interface NavigableMap<K,V>
fromKey
- low endpoint of the keys in the returned mapfromInclusive
- true
if the low endpoint is to be included in the returned viewtoKey
- high endpoint of the keys in the returned maptoInclusive
- true
if the high endpoint is to be included in the returned viewfromKey
to toKey
ClassCastException
- if fromKey
and toKey
cannot be compared to one another using this map's comparator (or, if the map has no comparator, using natural ordering). Implementations may, but are not required to, throw this exception if fromKey
or toKey
cannot be compared to keys currently in the map.NullPointerException
- if fromKey
or toKey
is nullIllegalArgumentException
- if fromKey
is greater than toKey
; or if this map itself has a restricted range, and fromKey
or toKey
lies outside the bounds of the rangepublic ConcurrentNavigableMap<K,V> headMap(K toKey, boolean inclusive)
NavigableMap
inclusive
is true) toKey
. The returned map is backed by this map, so changes in the returned map are reflected in this map, and vice-versa. The returned map supports all optional map operations that this map supports. The returned map will throw an IllegalArgumentException
on an attempt to insert a key outside its range.
headMap
in interface ConcurrentNavigableMap<K,V>
headMap
in interface NavigableMap<K,V>
toKey
- high endpoint of the keys in the returned mapinclusive
- true
if the high endpoint is to be included in the returned viewinclusive
is true) toKey
ClassCastException
- if toKey
is not compatible with this map's comparator (or, if the map has no comparator, if toKey
does not implement Comparable
). Implementations may, but are not required to, throw this exception if toKey
cannot be compared to keys currently in the map.NullPointerException
- if toKey
is nullIllegalArgumentException
- if this map itself has a restricted range, and toKey
lies outside the bounds of the rangepublic ConcurrentNavigableMap<K,V> tailMap(K fromKey, boolean inclusive)
NavigableMap
inclusive
is true) fromKey
. The returned map is backed by this map, so changes in the returned map are reflected in this map, and vice-versa. The returned map supports all optional map operations that this map supports. The returned map will throw an IllegalArgumentException
on an attempt to insert a key outside its range.
tailMap
in interface ConcurrentNavigableMap<K,V>
tailMap
in interface NavigableMap<K,V>
fromKey
- low endpoint of the keys in the returned mapinclusive
- true
if the low endpoint is to be included in the returned viewinclusive
is true) fromKey
ClassCastException
- if fromKey
is not compatible with this map's comparator (or, if the map has no comparator, if fromKey
does not implement Comparable
). Implementations may, but are not required to, throw this exception if fromKey
cannot be compared to keys currently in the map.NullPointerException
- if fromKey
is nullIllegalArgumentException
- if this map itself has a restricted range, and fromKey
lies outside the bounds of the rangepublic ConcurrentNavigableMap<K,V> subMap(K fromKey, K toKey)
NavigableMap
fromKey
, inclusive, to toKey
, exclusive. (If fromKey
and toKey
are equal, the returned map is empty.) The returned map is backed by this map, so changes in the returned map are reflected in this map, and vice-versa. The returned map supports all optional map operations that this map supports. The returned map will throw an IllegalArgumentException
on an attempt to insert a key outside its range.
Equivalent to subMap(fromKey, true, toKey, false)
.
subMap
in interface ConcurrentNavigableMap<K,V>
subMap
in interface NavigableMap<K,V>
subMap
in interface SortedMap<K,V>
fromKey
- low endpoint (inclusive) of the keys in the returned maptoKey
- high endpoint (exclusive) of the keys in the returned mapfromKey
, inclusive, to toKey
, exclusiveClassCastException
- if fromKey
and toKey
cannot be compared to one another using this map's comparator (or, if the map has no comparator, using natural ordering). Implementations may, but are not required to, throw this exception if fromKey
or toKey
cannot be compared to keys currently in the map.NullPointerException
- if fromKey
or toKey
is nullIllegalArgumentException
- if fromKey
is greater than toKey
; or if this map itself has a restricted range, and fromKey
or toKey
lies outside the bounds of the rangepublic ConcurrentNavigableMap<K,V> headMap(K toKey)
NavigableMap
toKey
. The returned map is backed by this map, so changes in the returned map are reflected in this map, and vice-versa. The returned map supports all optional map operations that this map supports. The returned map will throw an IllegalArgumentException
on an attempt to insert a key outside its range.
Equivalent to headMap(toKey, false)
.
headMap
in interface ConcurrentNavigableMap<K,V>
headMap
in interface NavigableMap<K,V>
headMap
in interface SortedMap<K,V>
toKey
- high endpoint (exclusive) of the keys in the returned maptoKey
ClassCastException
- if toKey
is not compatible with this map's comparator (or, if the map has no comparator, if toKey
does not implement Comparable
). Implementations may, but are not required to, throw this exception if toKey
cannot be compared to keys currently in the map.NullPointerException
- if toKey
is nullIllegalArgumentException
- if this map itself has a restricted range, and toKey
lies outside the bounds of the rangepublic ConcurrentNavigableMap<K,V> tailMap(K fromKey)
NavigableMap
fromKey
. The returned map is backed by this map, so changes in the returned map are reflected in this map, and vice-versa. The returned map supports all optional map operations that this map supports. The returned map will throw an IllegalArgumentException
on an attempt to insert a key outside its range.
Equivalent to tailMap(fromKey, true)
.
tailMap
in interface ConcurrentNavigableMap<K,V>
tailMap
in interface NavigableMap<K,V>
tailMap
in interface SortedMap<K,V>
fromKey
- low endpoint (inclusive) of the keys in the returned mapfromKey
ClassCastException
- if fromKey
is not compatible with this map's comparator (or, if the map has no comparator, if fromKey
does not implement Comparable
). Implementations may, but are not required to, throw this exception if fromKey
cannot be compared to keys currently in the map.NullPointerException
- if fromKey
is nullIllegalArgumentException
- if this map itself has a restricted range, and fromKey
lies outside the bounds of the rangepublic Map.Entry<K,V> lowerEntry(K key)
null
if there is no such key. The returned entry does not support the Entry.setValue
method.lowerEntry
in interface NavigableMap<K,V>
key
- the keykey
, or null
if there is no such keyClassCastException
- if the specified key cannot be compared with the keys currently in the mapNullPointerException
- if the specified key is nullpublic K lowerKey(K key)
NavigableMap
null
if there is no such key.lowerKey
in interface NavigableMap<K,V>
key
- the keykey
, or null
if there is no such keyClassCastException
- if the specified key cannot be compared with the keys currently in the mapNullPointerException
- if the specified key is nullpublic Map.Entry<K,V> floorEntry(K key)
null
if there is no such key. The returned entry does not support the Entry.setValue
method.floorEntry
in interface NavigableMap<K,V>
key
- the keykey
, or null
if there is no such keyClassCastException
- if the specified key cannot be compared with the keys currently in the mapNullPointerException
- if the specified key is nullpublic K floorKey(K key)
NavigableMap
null
if there is no such key.floorKey
in interface NavigableMap<K,V>
key
- the keykey
, or null
if there is no such keyClassCastException
- if the specified key cannot be compared with the keys currently in the mapNullPointerException
- if the specified key is nullpublic Map.Entry<K,V> ceilingEntry(K key)
null
if there is no such entry. The returned entry does not support the Entry.setValue
method.ceilingEntry
in interface NavigableMap<K,V>
key
- the keykey
, or null
if there is no such keyClassCastException
- if the specified key cannot be compared with the keys currently in the mapNullPointerException
- if the specified key is nullpublic K ceilingKey(K key)
NavigableMap
null
if there is no such key.ceilingKey
in interface NavigableMap<K,V>
key
- the keykey
, or null
if there is no such keyClassCastException
- if the specified key cannot be compared with the keys currently in the mapNullPointerException
- if the specified key is nullpublic Map.Entry<K,V> higherEntry(K key)
null
if there is no such key. The returned entry does not support the Entry.setValue
method.higherEntry
in interface NavigableMap<K,V>
key
- the keykey
, or null
if there is no such keyClassCastException
- if the specified key cannot be compared with the keys currently in the mapNullPointerException
- if the specified key is nullpublic K higherKey(K key)
NavigableMap
null
if there is no such key.higherKey
in interface NavigableMap<K,V>
key
- the keykey
, or null
if there is no such keyClassCastException
- if the specified key cannot be compared with the keys currently in the mapNullPointerException
- if the specified key is nullpublic Map.Entry<K,V> firstEntry()
null
if the map is empty. The returned entry does not support the Entry.setValue
method.firstEntry
in interface NavigableMap<K,V>
firstEntry
in interface SequencedMap<K,V>
null
if this map is emptypublic Map.Entry<K,V> lastEntry()
null
if the map is empty. The returned entry does not support the Entry.setValue
method.lastEntry
in interface NavigableMap<K,V>
lastEntry
in interface SequencedMap<K,V>
null
if this map is emptypublic Map.Entry<K,V> pollFirstEntry()
null
if the map is empty. The returned entry does not support the Entry.setValue
method.pollFirstEntry
in interface NavigableMap<K,V>
pollFirstEntry
in interface SequencedMap<K,V>
null
if this map is emptypublic Map.Entry<K,V> pollLastEntry()
null
if the map is empty. The returned entry does not support the Entry.setValue
method.pollLastEntry
in interface NavigableMap<K,V>
pollLastEntry
in interface SequencedMap<K,V>
null
if this map is empty
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Documentation extracted from Debian's OpenJDK Development Kit package.
Licensed under the GNU General Public License, version 2, with the Classpath Exception.
Various third party code in OpenJDK is licensed under different licenses (see Debian package).
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https://docs.oracle.com/en/java/javase/21/docs/api/java.base/java/util/concurrent/ConcurrentSkipListMap.html