public class TreeMultimap<K,V> extends Object
Multimap whose keys and values are ordered by
their natural ordering or by supplied comparators. In all cases, this
implementation uses Comparable.compareTo(T) or Comparator.compare(T, T) instead of Object.equals(java.lang.Object) to determine
equivalence of instances.
Warning: The comparators or comparables used must be consistent
with equals as explained by the Comparable class specification.
Otherwise, the resulting multiset will violate the general contract of SetMultimap, which it is specified in terms of Object.equals(java.lang.Object).
The collections returned by keySet and asMap iterate
through the keys according to the key comparator ordering or the natural
ordering of the keys. Similarly, get, removeAll, and replaceValues return collections that iterate through the values according
to the value comparator ordering or the natural ordering of the values. The
collections generated by entries, keys, and values
iterate across the keys according to the above key ordering, and for each
key they iterate across the values according to the value ordering.
The multimap does not store duplicate key-value pairs. Adding a new key-value pair equal to an existing key-value pair has no effect.
Null keys and values are permitted (provided, of course, that the respective comparators support them). All optional multimap methods are supported, and all returned views are modifiable.
This class is not threadsafe when any concurrent operations update the
multimap. Concurrent read operations will work correctly. To allow concurrent
update operations, wrap your multimap with a call to Multimaps#synchronizedSortedSetMultimap.
See the Guava User Guide article on
Multimap.
| Modifier and Type | Method and Description |
|---|---|
NavigableMap<K,Collection<V>> |
asMap()
Returns a map view that associates each key with the corresponding values
in the multimap.
|
void |
clear()
Removes all key-value pairs from the multimap, leaving it empty.
|
boolean |
containsEntry(Object key,
Object value)
Returns
true if this multimap contains at least one key-value pair
with the key key and the value value. |
boolean |
containsKey(Object key)
Returns
true if this multimap contains at least one key-value pair
with the key key. |
boolean |
containsValue(Object value)
Returns
true if this multimap contains at least one key-value pair
with the value value. |
static <K extends Comparable,V extends Comparable> |
create()
Creates an empty
TreeMultimap ordered by the natural ordering of
its keys and values. |
Set<Map.Entry<K,V>> |
entries()
Returns a view collection of all key-value pairs contained in this
multimap, as
Map.Entry instances. |
boolean |
equals(Object object)
Compares the specified object to this multimap for equality.
|
NavigableSet<V> |
get(K key)
Returns a collection view of all values associated with a key.
|
int |
hashCode()
Returns the hash code for this multimap.
|
NavigableSet<K> |
keySet()
Returns a view collection of all distinct keys contained in this
multimap.
|
boolean |
put(K key,
V value)
Stores a key-value pair in the multimap.
|
boolean |
putAll(K key,
Iterable<? extends V> values)
Stores a key-value pair in this multimap for each of
values, all
using the same key, key. |
boolean |
remove(Object key,
Object value)
Removes a single key-value pair with the key
key and the value
value from this multimap, if such exists. |
SortedSet<V> |
removeAll(Object key)
Removes all values associated with a given key.
|
int |
size()
Returns the number of key-value pairs in this multimap.
|
String |
toString()
Returns a string representation of the multimap, generated by calling
toString on the map returned by Multimap.asMap(). |
Comparator<? super V> |
valueComparator()
Returns the comparator that orders the multimap values, with
null
indicating that natural ordering is used. |
Collection<V> |
values()
Returns a view collection containing the value from each key-value
pair contained in this multimap, without collapsing duplicates (so
values().size() == size()). |
clone, finalize, getClass, notify, notifyAll, wait, wait, waitentries, equalsclear, containsEntry, containsKey, containsValue, hashCode, put, putAll, remove, sizepublic static <K extends Comparable,V extends Comparable> TreeMultimap<K,V> create()
TreeMultimap ordered by the natural ordering of
its keys and values.public Comparator<? super V> valueComparator()
SortedSetMultimapnull
indicating that natural ordering is used.public NavigableSet<V> get(K key)
Changes to the returned collection will update the underlying multimap, and vice versa.
Because a SortedSetMultimap has unique sorted values for a given
key, this method returns a SortedSet, instead of the
Collection specified in the Multimap interface.
public NavigableSet<K> keySet()
Changes to the returned set will update the underlying multimap, and vice versa. However, adding to the returned set is not possible.
Because a TreeMultimap has unique sorted keys, this method
returns a NavigableSet, instead of the Set specified
in the Multimap interface.
public NavigableMap<K,Collection<V>> asMap()
setValue
on its entries, put, or putAll.
When passed a key that is present in the map, asMap().get(Object) has the same behavior as get(K), returning a
live collection. When passed a key that is not present, however, asMap().get(Object) returns null instead of an empty collection.
Though the method signature doesn't say so explicitly, the returned map
has SortedSet values.
Because a TreeMultimap has unique sorted keys, this method
returns a NavigableMap, instead of the Map specified
in the Multimap interface.
public SortedSet<V> removeAll(Object key)
Because a SortedSetMultimap has unique sorted values for a given
key, this method returns a SortedSet, instead of the
Collection specified in the Multimap interface.
removeAll in interface Multimap<K,V>removeAll in interface SetMultimap<K,V>removeAll in interface SortedSetMultimap<K,V>public Collection<V> values()
values().size() == size()).
Changes to the returned collection will update the underlying multimap, and vice versa. However, adding to the returned collection is not possible.
The iterator generated by the returned collection traverses the values for one key, followed by the values of a second key, and so on.
Consequently, the values do not follow their natural ordering or the ordering of the value comparator.
public Set<Map.Entry<K,V>> entries()
Map.Entry instances.
Changes to the returned collection or the entries it contains will update the underlying multimap, and vice versa. However, adding to the returned collection is not possible.
The iterator generated by the returned collection traverses the values for one key, followed by the values of a second key, and so on.
Each entry is an immutable snapshot of a key-value mapping in the multimap, taken at the time the entry is returned by a method call to the collection or its iterator.
Because a SetMultimap has unique values for a given key, this
method returns a Set, instead of the Collection specified
in the Multimap interface.
public boolean equals(Object object)
Two SetMultimap instances are equal if, for each key, they
contain the same values. Equality does not depend on the ordering of keys
or values.
public int size()
Multimap
Note: this method does not return the number of distinct
keys in the multimap, which is given by keySet().size() or
asMap().size(). See the opening section of the Multimap
class documentation for clarification.
public boolean containsKey(Object key)
Multimaptrue if this multimap contains at least one key-value pair
with the key key.containsKey in interface Multimap<K,V>public void clear()
Multimappublic boolean containsValue(Object value)
Multimaptrue if this multimap contains at least one key-value pair
with the value value.containsValue in interface Multimap<K,V>public boolean containsEntry(Object key, Object value)
Multimaptrue if this multimap contains at least one key-value pair
with the key key and the value value.containsEntry in interface Multimap<K,V>public boolean remove(Object key, Object value)
Multimapkey and the value
value from this multimap, if such exists. If multiple key-value
pairs in the multimap fit this description, which one is removed is
unspecified.public boolean putAll(K key, Iterable<? extends V> values)
Multimapvalues, all
using the same key, key. Equivalent to (but expected to be more
efficient than):
<p>
for (V value : values) {
put(key, value);
}
In particular, this is a no-op if values is empty.
public int hashCode()
The hash code of a multimap is defined as the hash code of the map view,
as returned by Multimap.asMap().
public String toString()
toString on the map returned by Multimap.asMap().Copyright © 2007-2024, Oracle and/or its affiliates. All Rights Reserved. Use is subject to license terms.