@GwtCompatible(serializable=true, emulated=true) public class TreeMultimap<K,V> extends Object
Implementation of 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(com.diffplug.common.collect.SortedSetMultimap<K, V>).
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. |
static <K,V> TreeMultimap<K,V> |
create(Comparator<? super K> keyComparator,
Comparator<? super V> valueComparator)
Creates an empty
TreeMultimap instance using explicit comparators. |
static <K extends Comparable,V extends Comparable> |
create(Multimap<? extends K,? extends V> multimap)
Constructs a
TreeMultimap, ordered by the natural ordering of its keys and values, with the same mappings as the specified multimap. |
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.
|
boolean |
isEmpty()
Returns
true if this multimap contains no key-value pairs. |
Comparator<? super K> |
keyComparator()
Returns the comparator that orders the multimap keys.
|
Multiset<K> |
keys()
Returns a view collection containing the key from each key-value pair in this multimap, without collapsing duplicates.
|
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 |
putAll(Multimap<? extends K,? extends V> multimap)
Stores all key-value pairs of
multimap in this multimap, in the order returned by multimap.entries(). |
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.
|
SortedSet<V> |
replaceValues(K key,
Iterable<? extends V> values)
Stores a collection of values with the same key, replacing any existing
values for that 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, isEmpty, keys, put, putAll, putAll, remove, sizepublic static <K extends Comparable,V extends Comparable> TreeMultimap<K,V> create()
Creates an empty TreeMultimap ordered by the natural ordering of its keys and values.
public static <K,V> TreeMultimap<K,V> create(Comparator<? super K> keyComparator, Comparator<? super V> valueComparator)
Creates an empty TreeMultimap instance using explicit comparators. Neither comparator may be null; use Ordering.natural() to specify natural order.
keyComparator - the comparator that determines the key orderingvalueComparator - the comparator that determines the value orderingpublic static <K extends Comparable,V extends Comparable> TreeMultimap<K,V> create(Multimap<? extends K,? extends V> multimap)
Constructs a TreeMultimap, ordered by the natural ordering of its keys and values, with the same mappings as the specified multimap.
multimap - the multimap whose contents are copied to this multimappublic Comparator<? super K> keyComparator()
Returns the comparator that orders the multimap keys.
public Comparator<? super V> valueComparator()
SortedSetMultimapReturns the comparator that orders the multimap values, with null indicating that natural ordering is used.
@GwtIncompatible(value="NavigableSet") public NavigableSet<V> get(@Nullable 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.
@GwtIncompatible(value="NavigableSet") public NavigableSet<K> keySet()
Returns a view collection of all distinct keys contained in this multimap. Note that the key set contains a key if and only if this multimap maps that key to at least one value.
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.
@GwtIncompatible(value="NavigableMap") public NavigableMap<K,Collection<V>> asMap()
Returns a map view that associates each key with the corresponding values
in the multimap. Changes to the returned map, such as element removal, will
update the underlying multimap. The map does not support 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(@Nullable 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 SortedSet<V> replaceValues(@Nullable K key, Iterable<? extends V> values)
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.
Any duplicates in values will be stored in the multimap once.
replaceValues in interface Multimap<K,V>replaceValues in interface SetMultimap<K,V>replaceValues in interface SortedSetMultimap<K,V>public 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()).
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()
Returns a view collection of all key-value pairs contained in this multimap, as 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(@Nullable 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()
MultimapReturns the number of key-value pairs in this 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(@Nullable Object key)
MultimapReturns true if this multimap contains at least one key-value pair with the key key.
containsKey in interface Multimap<K,V>public void clear()
MultimapRemoves all key-value pairs from the multimap, leaving it empty.
public boolean isEmpty()
MultimapReturns true if this multimap contains no key-value pairs. Equivalent to size() == 0, but can in some cases be more efficient.
public boolean containsValue(@Nullable Object value)
MultimapReturns true if this multimap contains at least one key-value pair with the value value.
containsValue in interface Multimap<K,V>public boolean containsEntry(@Nullable Object key, @Nullable Object value)
MultimapReturns true 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(@Nullable Object key, @Nullable Object value)
MultimapRemoves a single key-value pair with the key key 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(@Nullable K key, Iterable<? extends V> values)
MultimapStores a key-value pair in this multimap for each of values, all using the same key, key. Equivalent to (but expected to be more efficient than):
for (V value : values) {
put(key, value);
}
In particular, this is a no-op if values is empty.
public boolean putAll(Multimap<? extends K,? extends V> multimap)
MultimapStores all key-value pairs of multimap in this multimap, in the order returned by multimap.entries().
public Multiset<K> keys()
MultimapReturns a view collection containing the key from each key-value pair in this multimap, without collapsing duplicates. This collection has the same size as this multimap, and keys().count(k) ==
get(k).size() for all k.
Changes to the returned multiset will update the underlying multimap, and vice versa. However, adding to the returned collection is not possible.
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().