K - the type of keys maintained by this mapV - the type of mapped valuespublic classTreeMap<K,V>extendsAbstractMap<K,V>implementsNavigableMap<K,V>,Cloneable,Serializable
NavigableMap implementation. The map is sorted according to thenatural ordering of its keys, or by aComparator provided at map creation time, depending on which constructor is used.This implementation provides guaranteed log(n) time cost for thecontainsKey,get,put andremove operations. Algorithms are adaptations of those in Cormen, Leiserson, and Rivest'sIntroduction to Algorithms.
Note that the ordering maintained by a tree map, like any sorted map, and whether or not an explicit comparator is provided, must beconsistent withequals if this sorted map is to correctly implement theMap interface. (SeeComparable orComparator for a precise definition ofconsistent with equals.) This is so because theMap interface is defined in terms of theequals operation, but a sorted map performs all key comparisons using itscompareTo (orcompare) method, so two keys that are deemed equal by this method are, from the standpoint of the sorted map, equal. The behavior of a sorted mapis well-defined even if its ordering is inconsistent withequals; it just fails to obey the general contract of theMap interface.
Note that this implementation is not synchronized. If multiple threads access a map concurrently, and at least one of the threads modifies the map structurally, itmust be synchronized externally. (A structural modification is any operation that adds or deletes one or more mappings; merely changing the value associated with an existing key is not a structural modification.) This is typically accomplished by synchronizing on some object that naturally encapsulates the map. If no such object exists, the map should be "wrapped" using theCollections.synchronizedSortedMap method. This is best done at creation time, to prevent accidental unsynchronized access to the map:
SortedMap m = Collections.synchronizedSortedMap(new TreeMap(...));
The iterators returned by theiterator method of the collections returned by all of this class's "collection view methods" arefail-fast: if the map is structurally modified at any time after the iterator is created, in any way except through the iterator's ownremove method, the iterator will throw aConcurrentModificationException. Thus, in the face of concurrent modification, the iterator fails quickly and cleanly, rather than risking arbitrary, non-deterministic behavior at an undetermined time in the future.
Note that the fail-fast behavior of an iterator cannot be guaranteed as it is, generally speaking, impossible to make any hard guarantees in the presence of unsynchronized concurrent modification. Fail-fast iterators throwConcurrentModificationException on a best-effort basis. Therefore, it would be wrong to write a program that depended on this exception for its correctness:the fail-fast behavior of iterators should be used only to detect bugs.
AllMap.Entry pairs returned by methods in this class and its views represent snapshots of mappings at the time they were produced. They donot support theEntry.setValue method. (Note however that it is possible to change mappings in the associated map usingput.)
This class is a member of the Java Collections Framework.
Map,HashMap,Hashtable,Comparable,Comparator,Collection,Serialized FormAbstractMap.SimpleEntry<K,V>,AbstractMap.SimpleImmutableEntry<K,V>| Constructor | Description |
|---|---|
TreeMap() | Constructs a new, empty tree map, using the natural ordering of its keys. |
TreeMap(Comparator<? superK> comparator) | Constructs a new, empty tree map, ordered according to the given comparator. |
TreeMap(Map<? extendsK,? extendsV> m) | Constructs a new tree map containing the same mappings as the given map, ordered according to thenatural ordering of its keys. |
TreeMap(SortedMap<K,? extendsV> m) | Constructs a new tree map containing the same mappings and using the same ordering as the specified sorted map. |
| Modifier and Type | Method | 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 key. |
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. |
Object | clone() | Returns a shallow copy of this TreeMap instance. |
Comparator<? superK> | comparator() | Returns the comparator used to order the keys in this map, or null if this map uses thenatural ordering of its keys. |
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. |
NavigableMap<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. |
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<? superK,? superV> 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. |
SortedMap<K,V> | headMap(K toKey) | Returns a view of the portion of this map whose keys are strictly less than toKey. |
NavigableMap<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. |
Set<K> | keySet() | Returns a Set 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. |
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. |
void | putAll(Map<? extendsK,? extendsV> map) | Copies all of the mappings from the specified map to this map. |
V | remove(Object key) | Removes the mapping for this key from this TreeMap if present. |
V | replace(K key,V value) | Replaces the entry for the specified key only if it is currently mapped to some value. |
boolean | replace(K key,V oldValue,V newValue) | Replaces the entry for the specified key only if currently mapped to the specified value. |
void | replaceAll(BiFunction<? superK,? superV,? extendsV> 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. |
NavigableMap<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 totoKey. |
SortedMap<K,V> | subMap(K fromKey,K toKey) | Returns a view of the portion of this map whose keys range from fromKey, inclusive, totoKey, exclusive. |
SortedMap<K,V> | tailMap(K fromKey) | Returns a view of the portion of this map whose keys are greater than or equal to fromKey. |
NavigableMap<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. |
equals,hashCode,isEmpty,toStringcompute,computeIfAbsent,computeIfPresent,equals,getOrDefault,hashCode,isEmpty,merge,putIfAbsent,removepublic TreeMap()
Comparable interface. Furthermore, all such keys must bemutually comparable:k1.compareTo(k2) must not throw aClassCastException for any keysk1 andk2 in the map. If the user attempts to put a key into the map that violates this constraint (for example, the user attempts to put a string key into a map whose keys are integers), theput(Object key, Object value) call will throw aClassCastException.public TreeMap(Comparator<? superK> comparator)
comparator.compare(k1, k2) must not throw aClassCastException for any keysk1 andk2 in the map. If the user attempts to put a key into the map that violates this constraint, theput(Object key, Object value) call will throw aClassCastException.comparator - the comparator that will be used to order this map. Ifnull, thenatural ordering of the keys will be used.public TreeMap(Map<? extendsK,? extendsV> m)
Comparable interface. Furthermore, all such keys must bemutually comparable:k1.compareTo(k2) must not throw aClassCastException for any keysk1 andk2 in the map. This method runs in n*log(n) time.m - the map whose mappings are to be placed in this mapClassCastException - if the keys in m are notComparable, or are not mutually comparableNullPointerException - if the specified map is nullpublic TreeMap(SortedMap<K,? extendsV> 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 map is nullpublic int size()
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 null and this map uses natural ordering, or its comparator does not permit null keyspublic boolean containsValue(Object value)
true if this map maps one or more keys to the specified value. More formally, returnstrue if and only if this map contains at least one mapping to a valuev such that(value==null ? v==null : value.equals(v)). This operation will probably require time linear in the map size for most implementations.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 tovalue exists;false otherwisepublic V get(Object key)
null if this map contains no mapping for the key.More formally, if this map contains a mapping from a keyk to a valuev such thatkey compares equal tok according to the map's ordering, then this method returnsv; otherwise it returnsnull. (There can be at most one such mapping.)
A return value ofnull does notnecessarily indicate that the map contains no mapping for the key; it's also possible that the map explicitly maps the key tonull. ThecontainsKey operation may be used to distinguish these two cases.
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 null and this map uses natural ordering, or its comparator does not permit null keyspublic Comparator<? superK> comparator()
SortedMapnull if this map uses thenatural 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 void putAll(Map<? extendsK,? extendsV> map)
putAll in interface Map<K,V>putAll in class AbstractMap<K,V>map - mappings to be stored in this mapClassCastException - if the class of a key or value in the specified map prevents it from being stored in this mapNullPointerException - if the specified map is null or the specified map contains a null key and this map does not permit null keyspublic 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 keykey, ornull if there was no mapping forkey. (Anull return can also indicate that the map previously associatednull withkey.)ClassCastException - if the specified key cannot be compared with the keys currently in the mapNullPointerException - if the specified key is null and this map uses natural ordering, or its comparator does not permit null keyspublic V remove(Object key)
remove in interface Map<K,V>remove in class AbstractMap<K,V>key - key for which mapping should be removedkey, ornull if there was no mapping forkey. (Anull return can also indicate that the map previously associatednull withkey.)ClassCastException - if the specified key cannot be compared with the keys currently in the mapNullPointerException - if the specified key is null and this map uses natural ordering, or its comparator does not permit null keyspublic void clear()
public Object clone()
TreeMap instance. (The keys and values themselves are not cloned.)clone in class AbstractMap<K,V>Cloneablepublic Map.Entry<K,V> firstEntry()
NavigableMapnull if the map is empty.firstEntry in interface NavigableMap<K,V>null if this map is emptypublic Map.Entry<K,V> lastEntry()
NavigableMapnull if the map is empty.lastEntry in interface NavigableMap<K,V>null if this map is emptypublic Map.Entry<K,V> pollFirstEntry()
NavigableMapnull if the map is empty.pollFirstEntry in interface NavigableMap<K,V>null if this map is emptypublic Map.Entry<K,V> pollLastEntry()
NavigableMapnull if the map is empty.pollLastEntry in interface NavigableMap<K,V>null if this map is emptypublic Map.Entry<K,V> lowerEntry(K key)
NavigableMapnull if there is no such key.lowerEntry in interface NavigableMap<K,V>key - the keykey, ornull 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 null and this map uses natural ordering, or its comparator does not permit null keyspublic K lowerKey(K key)
NavigableMapnull if there is no such key.lowerKey in interface NavigableMap<K,V>key - the keykey, ornull 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 null and this map uses natural ordering, or its comparator does not permit null keyspublic Map.Entry<K,V> floorEntry(K key)
NavigableMapnull if there is no such key.floorEntry in interface NavigableMap<K,V>key - the keykey, ornull 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 null and this map uses natural ordering, or its comparator does not permit null keyspublic K floorKey(K key)
NavigableMapnull if there is no such key.floorKey in interface NavigableMap<K,V>key - the keykey, ornull 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 null and this map uses natural ordering, or its comparator does not permit null keyspublic Map.Entry<K,V> ceilingEntry(K key)
NavigableMapnull if there is no such key.ceilingEntry in interface NavigableMap<K,V>key - the keykey, ornull 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 null and this map uses natural ordering, or its comparator does not permit null keyspublic K ceilingKey(K key)
NavigableMapnull if there is no such key.ceilingKey in interface NavigableMap<K,V>key - the keykey, ornull 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 null and this map uses natural ordering, or its comparator does not permit null keyspublic Map.Entry<K,V> higherEntry(K key)
NavigableMapnull if there is no such key.higherEntry in interface NavigableMap<K,V>key - the keykey, ornull 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 null and this map uses natural ordering, or its comparator does not permit null keyspublic K higherKey(K key)
NavigableMapnull if there is no such key.higherKey in interface NavigableMap<K,V>key - the keykey, ornull 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 null and this map uses natural ordering, or its comparator does not permit null keyspublic Set<K> keySet()
Set view of the keys contained in this map.The set's iterator returns the keys in ascending order. The set's spliterator islate-binding,fail-fast, and additionally reportsSpliterator.SORTED andSpliterator.ORDERED with an encounter order that is ascending key order. The spliterator's comparator (seeSpliterator.getComparator()) isnull if the tree map's comparator (seecomparator()) isnull. Otherwise, the spliterator's comparator is the same as or imposes the same total ordering as the tree map's comparator.
The set is backed by the map, so changes to the map are reflected in the set, and vice-versa. If the map is modified while an iteration over the set is in progress (except through the iterator's ownremove operation), the results of the iteration are undefined. The set supports element removal, which removes the corresponding mapping from the map, via theIterator.remove,Set.remove,removeAll,retainAll, andclear operations. It does not support theadd oraddAll operations.
public NavigableSet<K> navigableKeySet()
NavigableMapNavigableSet 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. If the map is modified while an iteration over the set is in progress (except through the iterator's ownremove operation), the results of the iteration are undefined. The set supports element removal, which removes the corresponding mapping from the map, via theIterator.remove,Set.remove,removeAll,retainAll, andclear operations. It does not support theadd oraddAll operations.navigableKeySet in interface NavigableMap<K,V>public NavigableSet<K> descendingKeySet()
NavigableMapNavigableSet 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. If the map is modified while an iteration over the set is in progress (except through the iterator's ownremove operation), the results of the iteration are undefined. The set supports element removal, which removes the corresponding mapping from the map, via theIterator.remove,Set.remove,removeAll,retainAll, andclear operations. It does not support theadd oraddAll operations.descendingKeySet 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 collection's spliterator islate-binding,fail-fast, and additionally reportsSpliterator.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. If the map is modified while an iteration over the collection is in progress (except through the iterator's ownremove operation), the results of the iteration are undefined. The collection supports element removal, which removes the corresponding mapping from the map, via theIterator.remove,Collection.remove,removeAll,retainAll andclear operations. It does not support theadd oraddAll operations.
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 sets's spliterator islate-binding,fail-fast, and additionally reportsSpliterator.SORTED andSpliterator.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. If the map is modified while an iteration over the set is in progress (except through the iterator's ownremove operation, or through thesetValue operation on a map entry returned by the iterator) the results of the iteration are undefined. The set supports element removal, which removes the corresponding mapping from the map, via theIterator.remove,Set.remove,removeAll,retainAll andclear operations. It does not support theadd oraddAll operations.
public NavigableMap<K,V> descendingMap()
NavigableMapremove operation), the results of the iteration are undefined.The returned map has an ordering equivalent toCollections.reverseOrder(comparator()). The expressionm.descendingMap().descendingMap() returns a view ofm essentially equivalent tom.
descendingMap in interface NavigableMap<K,V>public NavigableMap<K,V> subMap(K fromKey, boolean fromInclusive,K toKey, boolean toInclusive)
NavigableMapfromKey totoKey. IffromKey andtoKey are equal, the returned map is empty unlessfromInclusive andtoInclusive 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 anIllegalArgumentException 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 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 totoKeyClassCastException - iffromKey andtoKey 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 iffromKey ortoKey cannot be compared to keys currently in the map.NullPointerException - iffromKey ortoKey is null and this map uses natural ordering, or its comparator does not permit null keysIllegalArgumentException - iffromKey is greater thantoKey; or if this map itself has a restricted range, andfromKey ortoKey lies outside the bounds of the rangepublic NavigableMap<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 anIllegalArgumentException on an attempt to insert a key outside its range.
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 - iftoKey is not compatible with this map's comparator (or, if the map has no comparator, iftoKey does not implementComparable). Implementations may, but are not required to, throw this exception iftoKey cannot be compared to keys currently in the map.NullPointerException - iftoKey is null and this map uses natural ordering, or its comparator does not permit null keysIllegalArgumentException - if this map itself has a restricted range, andtoKey lies outside the bounds of the rangepublic NavigableMap<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 anIllegalArgumentException on an attempt to insert a key outside its range.
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 - iffromKey is not compatible with this map's comparator (or, if the map has no comparator, iffromKey does not implementComparable). Implementations may, but are not required to, throw this exception iffromKey cannot be compared to keys currently in the map.NullPointerException - iffromKey is null and this map uses natural ordering, or its comparator does not permit null keysIllegalArgumentException - if this map itself has a restricted range, andfromKey lies outside the bounds of the rangepublic SortedMap<K,V> subMap(K fromKey,K toKey)
NavigableMapfromKey, inclusive, totoKey, exclusive. (IffromKey andtoKey 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 anIllegalArgumentException on an attempt to insert a key outside its range.
Equivalent tosubMap(fromKey, true, toKey, false).
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, totoKey, exclusiveClassCastException - iffromKey andtoKey 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 iffromKey ortoKey cannot be compared to keys currently in the map.NullPointerException - iffromKey ortoKey is null and this map uses natural ordering, or its comparator does not permit null keysIllegalArgumentException - iffromKey is greater thantoKey; or if this map itself has a restricted range, andfromKey ortoKey lies outside the bounds of the rangepublic SortedMap<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 anIllegalArgumentException on an attempt to insert a key outside its range.
Equivalent toheadMap(toKey, false).
headMap in interface NavigableMap<K,V>headMap in interface SortedMap<K,V>toKey - high endpoint (exclusive) of the keys in the returned maptoKeyClassCastException - iftoKey is not compatible with this map's comparator (or, if the map has no comparator, iftoKey does not implementComparable). Implementations may, but are not required to, throw this exception iftoKey cannot be compared to keys currently in the map.NullPointerException - iftoKey is null and this map uses natural ordering, or its comparator does not permit null keysIllegalArgumentException - if this map itself has a restricted range, andtoKey lies outside the bounds of the rangepublic SortedMap<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 anIllegalArgumentException on an attempt to insert a key outside its range.
Equivalent totailMap(fromKey, true).
tailMap in interface NavigableMap<K,V>tailMap in interface SortedMap<K,V>fromKey - low endpoint (inclusive) of the keys in the returned mapfromKeyClassCastException - iffromKey is not compatible with this map's comparator (or, if the map has no comparator, iffromKey does not implementComparable). Implementations may, but are not required to, throw this exception iffromKey cannot be compared to keys currently in the map.NullPointerException - iffromKey is null and this map uses natural ordering, or its comparator does not permit null keysIllegalArgumentException - if this map itself has a restricted range, andfromKey lies outside the bounds of the rangepublic boolean replace(K key,V oldValue,V newValue)
Mappublic V replace(K key,V value)
Mapreplace 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 key. (Anull return can also indicate that the map previously associatednull with the key, if the implementation supports null values.)public void forEach(BiConsumer<? superK,? superV> action)
Mappublic void replaceAll(BiFunction<? superK,? superV,? extendsV> function)
MapreplaceAll in interface Map<K,V>function - the function to apply to each entry