com.google.common.collect

Class Multimaps.MapMultimap<K,V>

java.lang.Object

com.google.common.collect.AbstractMultimap<K,V>

com.google.common.collect.Multimaps.MapMultimap<K,V>

All Implemented Interfaces:

Multimap<K,V>, SetMultimap<K,V>, java.io.Serializable

Enclosing class:

Multimaps

private static class Multimaps.MapMultimap<K,V>
extends AbstractMultimap<K,V>
implements SetMultimap<K,V>, java.io.Serializable

See Also:

Multimaps.forMap(java.util.Map<K, V>)

Nested Class Summary

Nested classes/interfaces inherited from class com.google.common.collect.AbstractMultimap

AbstractMultimap.Values

Field Summary

Fields

Modifier and Type	Field and Description
(package private) java.util.Map<K,V>	map
private static long	serialVersionUID

Constructor Summary

Constructors

Constructor and Description
MapMultimap(java.util.Map<K,V> map)

Method Summary

Modifier and Type	Method and Description
void	clear() Removes all key-value pairs from the multimap, leaving it empty.
boolean	containsEntry(java.lang.Object key, java.lang.Object value) Returns true if this multimap contains at least one key-value pair with the key key and the value value.
boolean	containsKey(java.lang.Object key) Returns true if this multimap contains at least one key-value pair with the key key.
boolean	containsValue(java.lang.Object value) Returns true if this multimap contains at least one key-value pair with the value value.
(package private) java.util.Map<K,java.util.Collection<V>>	createAsMap()
java.util.Set<java.util.Map.Entry<K,V>>	entries() Returns a view collection of all key-value pairs contained in this multimap, as Map.Entry instances.
(package private) java.util.Iterator<java.util.Map.Entry<K,V>>	entryIterator()
java.util.Set<V>	get(K key) Returns a view collection of the values associated with key in this multimap, if any.
int	hashCode() Returns the hash code for this multimap.
java.util.Set<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 this multimap.
boolean	putAll(K key, java.lang.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(java.lang.Object key, java.lang.Object value) Removes a single key-value pair with the key key and the value value from this multimap, if such exists.
java.util.Set<V>	removeAll(java.lang.Object key) Removes all values associated with the key key.
java.util.Set<V>	replaceValues(K key, java.lang.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.
java.util.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()).

Methods inherited from class com.google.common.collect.AbstractMultimap

asMap, createEntries, createKeys, createKeySet, createValues, equals, isEmpty, keys, toString, valueIterator

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface com.google.common.collect.SetMultimap

asMap, equals

Methods inherited from interface com.google.common.collect.Multimap

isEmpty, keys

Field Detail

map

final java.util.Map<K,V> map

serialVersionUID

private static final long serialVersionUID

See Also:

Constant Field Values

Constructor Detail

MapMultimap

MapMultimap(java.util.Map<K,V> map)

Method Detail

size

public int size()

Description copied from interface: Multimap

Returns 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.

Specified by:

size in interface Multimap<K,V>

containsKey

public boolean containsKey(java.lang.Object key)

Description copied from interface: Multimap

Returns true if this multimap contains at least one key-value pair with the key key.

Specified by:

containsKey in interface Multimap<K,V>

containsValue

public boolean containsValue(java.lang.Object value)

Description copied from interface: Multimap

Returns true if this multimap contains at least one key-value pair with the value value.

Specified by:

containsValue in interface Multimap<K,V>

Overrides:

containsValue in class AbstractMultimap<K,V>

containsEntry

public boolean containsEntry(java.lang.Object key,
                             java.lang.Object value)

Description copied from interface: Multimap

Returns true if this multimap contains at least one key-value pair with the key key and the value value.

Specified by:

containsEntry in interface Multimap<K,V>

Overrides:

containsEntry in class AbstractMultimap<K,V>

get

public java.util.Set<V> get(K key)

Description copied from interface: SetMultimap

Returns a view collection of the values associated with key in this multimap, if any. Note that when containsKey(key) is false, this returns an empty collection, not null.

Changes to the returned collection will update the underlying multimap, and vice versa.

Because a SetMultimap has unique values for a given key, this method returns a Set, instead of the Collection specified in the Multimap interface.

Specified by:

get in interface Multimap<K,V>

Specified by:

get in interface SetMultimap<K,V>

put

public boolean put(K key,
                   V value)

Description copied from interface: Multimap

Stores a key-value pair in this multimap.

Some multimap implementations allow duplicate key-value pairs, in which case put always adds a new key-value pair and increases the multimap size by 1. Other implementations prohibit duplicates, and storing a key-value pair that's already in the multimap has no effect.

Specified by:

put in interface Multimap<K,V>

Overrides:

put in class AbstractMultimap<K,V>

Returns:

true if the method increased the size of the multimap, or false if the multimap already contained the key-value pair and doesn't allow duplicates

putAll

public boolean putAll(K key,
                      java.lang.Iterable<? extends V> values)

Description copied from interface: Multimap

Stores 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.

Specified by:

putAll in interface Multimap<K,V>

Overrides:

putAll in class AbstractMultimap<K,V>

Returns:

true if the multimap changed

putAll

public boolean putAll(Multimap<? extends K,? extends V> multimap)

Description copied from interface: Multimap

Stores all key-value pairs of multimap in this multimap, in the order returned by multimap.entries().

Specified by:

putAll in interface Multimap<K,V>

Overrides:

putAll in class AbstractMultimap<K,V>

Returns:

true if the multimap changed

replaceValues

public java.util.Set<V> replaceValues(K key,
                                      java.lang.Iterable<? extends V> values)

Description copied from interface: Multimap

Stores a collection of values with the same key, replacing any existing values for that key.

If values is empty, this is equivalent to removeAll(key).

Specified by:

replaceValues in interface Multimap<K,V>

Specified by:

replaceValues in interface SetMultimap<K,V>

Overrides:

replaceValues in class AbstractMultimap<K,V>

Returns:

the collection of replaced values, or an empty collection if no values were previously associated with the key. The collection may be modifiable, but updating it will have no effect on the multimap.

remove

public boolean remove(java.lang.Object key,
                      java.lang.Object value)

Description copied from interface: Multimap

Removes 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.

Specified by:

remove in interface Multimap<K,V>

Overrides:

remove in class AbstractMultimap<K,V>

Returns:

true if the multimap changed

removeAll

public java.util.Set<V> removeAll(java.lang.Object key)

Description copied from interface: SetMultimap

Removes all values associated with the key key.

Once this method returns, key will not be mapped to any values, so it will not appear in Multimap.keySet(), Multimap.asMap(), or any other views.

Because a SetMultimap has unique values for a given key, this method returns a Set, instead of the Collection specified in the Multimap interface.

Specified by:

removeAll in interface Multimap<K,V>

Specified by:

removeAll in interface SetMultimap<K,V>

Returns:

the values that were removed (possibly empty). The returned collection may be modifiable, but updating it will have no effect on the multimap.

clear

public void clear()

Description copied from interface: Multimap

Removes all key-value pairs from the multimap, leaving it empty.

Specified by:

clear in interface Multimap<K,V>

keySet

public java.util.Set<K> keySet()

Description copied from interface: Multimap

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.

Specified by:

keySet in interface Multimap<K,V>

Overrides:

keySet in class AbstractMultimap<K,V>

values

public java.util.Collection<V> values()

Description copied from interface: Multimap

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.

Specified by:

values in interface Multimap<K,V>

Overrides:

values in class AbstractMultimap<K,V>

entries

public java.util.Set<java.util.Map.Entry<K,V>> entries()

Description copied from interface: Multimap

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.

Specified by:

entries in interface Multimap<K,V>

Specified by:

entries in interface SetMultimap<K,V>

Overrides:

entries in class AbstractMultimap<K,V>

entryIterator

java.util.Iterator<java.util.Map.Entry<K,V>> entryIterator()

Specified by:

entryIterator in class AbstractMultimap<K,V>

createAsMap

java.util.Map<K,java.util.Collection<V>> createAsMap()

Specified by:

createAsMap in class AbstractMultimap<K,V>

hashCode

public int hashCode()

Description copied from class: AbstractMultimap

Returns the hash code for this multimap.

The hash code of a multimap is defined as the hash code of the map view, as returned by Multimap.asMap().

Specified by:

hashCode in interface Multimap<K,V>

Overrides:

hashCode in class AbstractMultimap<K,V>

See Also:

Map.hashCode()