@GwtCompatible(serializable=true, emulated=true) 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(com.google.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.
|
boolean |
containsEntry(Object key,
Object value)
Returns
true if the multimap contains the specified key-value pair. |
boolean |
containsKey(Object key)
Returns
true if the multimap contains any values for the specified
key. |
boolean |
containsValue(Object value)
Returns
true if the multimap contains the specified value for any
key. |
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 collection of all key-value pairs.
|
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 the multimap contains no key-value pairs. |
Comparator<? super K> |
keyComparator()
Returns the comparator that orders the multimap keys.
|
Multiset<K> |
keys()
Returns a collection, which may contain duplicates, of all keys.
|
NavigableSet<K> |
keySet()
Returns the set of all keys, each appearing once in the returned set.
|
boolean |
put(K key,
V value)
Stores a key-value pair in the multimap.
|
boolean |
putAll(K key,
Iterable<? extends V> values)
Stores key-value pairs in this multimap with one key and multiple values.
|
boolean |
putAll(Multimap<? extends K,? extends V> multimap)
Copies all of another multimap's key-value pairs into this multimap.
|
boolean |
remove(Object key,
Object value)
Removes a single key-value pair from the multimap.
|
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 the 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 collection of all values in the multimap.
|
clone, finalize, getClass, notify, notifyAll, wait, wait, wait
entries, equals
clear, containsEntry, containsKey, containsValue, hashCode, isEmpty, keys, put, putAll, putAll, remove, size
public static <K extends Comparable,V extends Comparable> TreeMultimap<K,V> create()
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)
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)
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()
public Comparator<? super V> valueComparator()
SortedSetMultimap
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.
get
in interface Multimap<K,V>
get
in interface SetMultimap<K,V>
get
in interface SortedSetMultimap<K,V>
key
- key to search for in multimapSortedSet
since 2.0)@GwtIncompatible(value="NavigableSet") public NavigableSet<K> keySet()
Note that the key set contains a key if and only if this multimap maps that key to at least one value.
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()
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>
key
- key of entries to remove from the multimappublic 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>
key
- key to store in the multimapvalues
- values to store in the multimappublic Collection<V> values()
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()
add
or addAll
operations.
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.
entries
in interface Multimap<K,V>
entries
in interface SetMultimap<K,V>
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.
equals
in interface Multimap<K,V>
equals
in interface SetMultimap<K,V>
object
- the reference object with which to compare.true
if this object is the same as the obj
argument; false
otherwise.Object.hashCode()
,
HashMap
public int size()
Multimap
public boolean containsKey(@Nullable Object key)
Multimap
true
if the multimap contains any values for the specified
key.containsKey
in interface Multimap<K,V>
key
- key to search for in multimappublic void clear()
Multimap
public boolean isEmpty()
Multimap
true
if the multimap contains no key-value pairs.public boolean containsValue(@Nullable Object value)
Multimap
true
if the multimap contains the specified value for any
key.containsValue
in interface Multimap<K,V>
value
- value to search for in multimappublic boolean containsEntry(@Nullable Object key, @Nullable Object value)
Multimap
true
if the multimap contains the specified key-value pair.containsEntry
in interface Multimap<K,V>
key
- key to search for in multimapvalue
- value to search for in multimappublic boolean remove(@Nullable Object key, @Nullable Object value)
Multimap
public boolean putAll(@Nullable K key, Iterable<? extends V> values)
Multimap
This is equivalent to
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)
Multimap
multimap.entries()
.public Multiset<K> keys()
Multimap
public int hashCode()
The hash code of a multimap is defined as the hash code of the map view,
as returned by Multimap.asMap()
.
hashCode
in interface Multimap<K,V>
hashCode
in class Object
Map.hashCode()
public String toString()
toString
on the map returned by Multimap.asMap()
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