K - the type of keys maintained by this mapV - the type of mapped valuespublic 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, unlike in most collections, the size
method is not a constant-time operation. Because of the
asynchronous nature of these maps, determining the current number
of elements requires a traversal of the elements, and so may report
inaccurate results if this collection is modified during traversal.
Additionally, the 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 and Description |
|---|
ConcurrentSkipListMap()
Constructs a new, empty map, sorted according to the
natural ordering of the keys.
|
ConcurrentSkipListMap(Comparator<? super K> comparator)
Constructs a new, empty map, sorted according to the specified
comparator.
|
ConcurrentSkipListMap(Map<? extends K,? extends V> m)
Constructs a new map containing the same mappings as the given map,
sorted according to the natural ordering of
the keys.
|
ConcurrentSkipListMap(SortedMap<K,? extends V> m)
Constructs a new map containing the same mappings and using the
same ordering as the specified sorted map.
|
| Modifier and Type | Method and Description |
|---|---|
Map.Entry<K,V> |
ceilingEntry(K key)
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(K key)
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<K,V> |
clone()
Returns a shallow copy of this
ConcurrentSkipListMap
instance. |
Comparator<? super K> |
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(K key,
BiFunction<? super K,? super V,? extends V> remappingFunction)
Attempts to compute a mapping for the specified key and its
current mapped value (or
null if there is no current
mapping). |
V |
computeIfAbsent(K key,
Function<? super K,? extends V> mappingFunction)
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(K key,
BiFunction<? super K,? super V,? extends V> remappingFunction)
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(Object key)
Returns
true if this map contains a mapping for the specified
key. |
boolean |
containsValue(Object value)
Returns
true if this map maps one or more keys to the
specified value. |
NavigableSet<K> |
descendingKeySet()
Returns a reverse order
NavigableSet view of the keys contained in this map. |
ConcurrentNavigableMap<K,V> |
descendingMap()
Returns a reverse order view of the mappings contained in this map.
|
Set<Map.Entry<K,V>> |
entrySet()
Returns a
Set view of the mappings contained in this map. |
boolean |
equals(Object o)
Compares the specified object with this map for equality.
|
Map.Entry<K,V> |
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<K,V> |
floorEntry(K key)
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(K key)
Returns the greatest key less than or equal to the given key,
or
null if there is no such key. |
void |
forEach(BiConsumer<? super K,? super V> action)
Performs the given action for each entry in this map until all entries
have been processed or the action throws an exception.
|
V |
get(Object key)
Returns the value to which the specified key is mapped,
or
null if this map contains no mapping for the key. |
V |
getOrDefault(Object key,
V defaultValue)
Returns the value to which the specified key is mapped,
or the given defaultValue if this map contains no mapping for the key.
|
ConcurrentNavigableMap<K,V> |
headMap(K toKey)
Returns a view of the portion of this map whose keys are
strictly less than
toKey. |
ConcurrentNavigableMap<K,V> |
headMap(K toKey,
boolean inclusive)
Returns a view of the portion of this map whose keys are less than (or
equal to, if
inclusive is true) toKey. |
Map.Entry<K,V> |
higherEntry(K key)
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(K key)
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<K> |
keySet()
Returns a
NavigableSet view of the keys contained in this map. |
Map.Entry<K,V> |
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<K,V> |
lowerEntry(K key)
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(K key)
Returns the greatest key strictly less than the given key, or
null if there is no such key. |
V |
merge(K key,
V value,
BiFunction<? super V,? super V,? extends V> remappingFunction)
If the specified key is not already associated with a value,
associates it with the given value.
|
NavigableSet<K> |
navigableKeySet()
Returns a
NavigableSet view of the keys contained in this map. |
Map.Entry<K,V> |
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<K,V> |
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(K key,
V value)
Associates the specified value with the specified key in this map.
|
V |
putIfAbsent(K key,
V value)
If the specified key is not already associated
with a value, associate it with the given value.
|
V |
remove(Object key)
Removes the mapping for the specified key from this map if present.
|
boolean |
remove(Object key,
Object value)
Removes the entry for a key only if currently mapped to a given value.
|
V |
replace(K key,
V value)
Replaces the entry for a key only if currently mapped to some value.
|
boolean |
replace(K key,
V oldValue,
V newValue)
Replaces the entry for a key only if currently mapped to a given value.
|
void |
replaceAll(BiFunction<? super K,? super V,? extends V> function)
Replaces each entry's value with the result of invoking the given
function on that entry until all entries have been processed or the
function throws an exception.
|
int |
size()
Returns the number of key-value mappings in this map.
|
ConcurrentNavigableMap<K,V> |
subMap(K fromKey,
boolean fromInclusive,
K toKey,
boolean toInclusive)
Returns a view of the portion of this map whose keys range from
fromKey to toKey. |
ConcurrentNavigableMap<K,V> |
subMap(K fromKey,
K toKey)
Returns a view of the portion of this map whose keys range from
fromKey, inclusive, to toKey, exclusive. |
ConcurrentNavigableMap<K,V> |
tailMap(K fromKey)
Returns a view of the portion of this map whose keys are
greater than or equal to
fromKey. |
ConcurrentNavigableMap<K,V> |
tailMap(K fromKey,
boolean inclusive)
Returns a view of the portion of this map whose keys are greater than (or
equal to, if
inclusive is true) fromKey. |
Collection<V> |
values()
Returns a
Collection view of the values contained in this map. |
hashCode, putAll, toStringpublic 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>Cloneablepublic 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, it
returns Integer.MAX_VALUE.
Beware that, unlike in most collections, this method is NOT a constant-time operation. Because of the asynchronous nature of these maps, determining the current number of elements requires traversing them all to count them. Additionally, it is possible for the size to change during execution of this method, in which case the returned result will be inaccurate. Thus, this method is typically not very useful in concurrent applications.
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 (see
Spliterator.getComparator()) is null if
the map's comparator (see 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 NavigableSet<K> navigableKeySet()
ConcurrentNavigableMapNavigableSet view of the keys contained in this map.
The set's iterator returns the keys in ascending 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.
navigableKeySet in interface ConcurrentNavigableMap<K,V>navigableKeySet in interface NavigableMap<K,V>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()
ConcurrentNavigableMapThe 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()
ConcurrentNavigableMapNavigableSet 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.equals in interface Map<K,V>equals in class AbstractMap<K,V>o - object to be compared for equality with this maptrue if the specified object is equal to this mapObject.hashCode(),
HashMappublic V putIfAbsent(K key, V value)
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)
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)
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)
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()
SortedMapnull 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()
SortedMapfirstKey in interface SortedMap<K,V>NoSuchElementException - if this map is emptypublic K lastKey()
SortedMaplastKey in interface SortedMap<K,V>NoSuchElementException - if this map is emptypublic ConcurrentNavigableMap<K,V> subMap(K fromKey, boolean fromInclusive, K toKey, boolean toInclusive)
NavigableMapfromKey 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 toKeyClassCastException - 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)
NavigableMapinclusive 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) toKeyClassCastException - 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)
NavigableMapinclusive 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) fromKeyClassCastException - 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)
NavigableMapfromKey, 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)
NavigableMaptoKey. 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 maptoKeyClassCastException - 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)
NavigableMapfromKey. 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 mapfromKeyClassCastException - 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)
NavigableMapnull 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)
NavigableMapnull 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)
NavigableMapnull 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)
NavigableMapnull 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>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>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>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>null if this map is emptypublic void forEach(BiConsumer<? super K,? super V> action)
ConcurrentMappublic void replaceAll(BiFunction<? super K,? super V,? extends V> function)
ConcurrentMapreplaceAll in interface ConcurrentMap<K,V>replaceAll in interface Map<K,V>function - the function to apply to each entry Submit a bug or feature
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