Class ArrayListMultimap<K,V>
- All Implemented Interfaces:
ListMultimap<K,,V> Multimap<K,,V> Serializable
Multimap that uses an ArrayList to store the values for a given
key. A HashMap associates each key with an ArrayList of values.
When iterating through the collections supplied by this class, the ordering of values for a given key agrees with the order in which the values were added.
This multimap allows duplicate key-value pairs. After adding a new key-value pair equal to an
existing key-value pair, the ArrayListMultimap will contain entries for both the new
value and the old value.
Keys and values may be null. All optional multimap methods are supported, and all returned views are modifiable.
The lists returned by AbstractListMultimap.get(K), AbstractListMultimap.removeAll(java.lang.Object), and AbstractListMultimap.replaceValues(K, java.lang.Iterable<? extends V>) all
implement RandomAccess.
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.synchronizedListMultimap(com.google.common.collect.ListMultimap<K, V>).
See the Guava User Guide article on Multimap.
- Since:
- 2.0
- See Also:
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Nested Class Summary
Nested classes/interfaces inherited from class com.google.common.collect.AbstractMapBasedMultimap
AbstractMapBasedMultimap.NavigableAsMap, AbstractMapBasedMultimap.NavigableKeySet, AbstractMapBasedMultimap.WrappedCollection, AbstractMapBasedMultimap.WrappedList, AbstractMapBasedMultimap.WrappedNavigableSet, AbstractMapBasedMultimap.WrappedSet, AbstractMapBasedMultimap.WrappedSortedSetNested classes/interfaces inherited from class com.google.common.collect.AbstractMultimap
AbstractMultimap.Entries, AbstractMultimap.EntrySet, AbstractMultimap.Values -
Field Summary
FieldsModifier and TypeFieldDescriptionprivate static final int(package private) intprivate static final long -
Constructor Summary
ConstructorsModifierConstructorDescriptionprivateprivateArrayListMultimap(int expectedKeys, int expectedValuesPerKey) privateArrayListMultimap(Multimap<? extends K, ? extends V> multimap) -
Method Summary
Modifier and TypeMethodDescriptionstatic <K,V> ArrayListMultimap<K, V> create()Creates a new, emptyArrayListMultimapwith the default initial capacities.static <K,V> ArrayListMultimap<K, V> create(int expectedKeys, int expectedValuesPerKey) Constructs an emptyArrayListMultimapwith enough capacity to hold the specified numbers of keys and values without resizing.static <K,V> ArrayListMultimap<K, V> Constructs anArrayListMultimapwith the same mappings as the specified multimap.Creates a new, emptyArrayListto hold the collection of values for an arbitrary key.private voidreadObject(ObjectInputStream stream) voidDeprecated.private voidwriteObject(ObjectOutputStream stream) Methods inherited from class com.google.common.collect.AbstractListMultimap
asMap, createUnmodifiableEmptyCollection, equals, get, put, removeAll, replaceValues, unmodifiableCollectionSubclass, wrapCollectionMethods inherited from class com.google.common.collect.AbstractMapBasedMultimap
backingMap, clear, containsKey, createAsMap, createCollection, createEntries, createKeys, createKeySet, createMaybeNavigableAsMap, createMaybeNavigableKeySet, createValues, entries, entryIterator, entrySpliterator, forEach, setMap, size, valueIterator, values, valueSpliterator, wrapListMethods inherited from class com.google.common.collect.AbstractMultimap
containsEntry, containsValue, hashCode, isEmpty, keys, keySet, putAll, putAll, remove, toString
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Field Details
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DEFAULT_VALUES_PER_KEY
private static final int DEFAULT_VALUES_PER_KEY- See Also:
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expectedValuesPerKey
transient int expectedValuesPerKey -
serialVersionUID
private static final long serialVersionUID- See Also:
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Constructor Details
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ArrayListMultimap
private ArrayListMultimap() -
ArrayListMultimap
private ArrayListMultimap(int expectedKeys, int expectedValuesPerKey) -
ArrayListMultimap
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Method Details
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create
Creates a new, emptyArrayListMultimapwith the default initial capacities.This method will soon be deprecated in favor of
MultimapBuilder.hashKeys().arrayListValues().build(). -
create
Constructs an emptyArrayListMultimapwith enough capacity to hold the specified numbers of keys and values without resizing.This method will soon be deprecated in favor of
MultimapBuilder.hashKeys(expectedKeys).arrayListValues(expectedValuesPerKey).build().- Parameters:
expectedKeys- the expected number of distinct keysexpectedValuesPerKey- the expected average number of values per key- Throws:
IllegalArgumentException- ifexpectedKeysorexpectedValuesPerKeyis negative
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create
Constructs anArrayListMultimapwith the same mappings as the specified multimap.This method will soon be deprecated in favor of
MultimapBuilder.hashKeys().arrayListValues().build(multimap).- Parameters:
multimap- the multimap whose contents are copied to this multimap
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createCollection
Creates a new, emptyArrayListto hold the collection of values for an arbitrary key.- Specified by:
createCollectionin classAbstractListMultimap<K,V> - Returns:
- an empty collection of values
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trimToSize
Deprecated.For aListMultimapthat automatically trims to size, useImmutableListMultimap. If you need a mutable collection, remove thetrimToSizecall, or switch to aHashMap<K, ArrayList<V>>.Reduces the memory used by thisArrayListMultimap, if feasible. -
writeObject
- Throws:
IOException
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readObject
- Throws:
IOExceptionClassNotFoundException
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ListMultimapthat automatically trims to size, useImmutableListMultimap.