Class HashBiMap<K extends @Nullable Object,V extends @Nullable Object>
- java.lang.Object
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- java.util.AbstractMap<K,V>
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- com.google.common.collect.HashBiMap<K,V>
 
 
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- All Implemented Interfaces:
- BiMap<K,V>,- Serializable,- Map<K,V>
 
 @GwtCompatible public final class HashBiMap<K extends @Nullable Object,V extends @Nullable Object> extends AbstractMap<K,V> implements BiMap<K,V>, Serializable ABiMapbacked by two hash tables. This implementation allows null keys and values. AHashBiMapand its inverse are both serializable.This implementation guarantees insertion-based iteration order of its keys. See the Guava User Guide article on BiMap.- Since:
- 2.0
- Author:
- Louis Wasserman, Mike Bostock
- See Also:
- Serialized Form
 
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Nested Class Summary- 
Nested classes/interfaces inherited from class java.util.AbstractMapAbstractMap.SimpleEntry<K,V>, AbstractMap.SimpleImmutableEntry<K,V>
 
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Method SummaryAll Methods Static Methods Instance Methods Concrete Methods Modifier and Type Method Description voidclear()Removes all of the mappings from this map (optional operation).booleancontainsKey(Object key)Returnstrueif this map contains a mapping for the specified key.booleancontainsValue(Object value)Returnstrueif this BiMap contains an entry whose value is equal tovalue(or, equivalently, if this inverse view contains a key that is equal tovalue).static <K extends @Nullable Object,V extends @Nullable Object>
 HashBiMap<K,V>create()Returns a new, emptyHashBiMapwith the default initial capacity (16).static <K extends @Nullable Object,V extends @Nullable Object>
 HashBiMap<K,V>create(int expectedSize)Constructs a new, empty bimap with the specified expected size.static <K extends @Nullable Object,V extends @Nullable Object>
 HashBiMap<K,V>create(Map<? extends K,? extends V> map)Constructs a new bimap containing initial values frommap.Set<Map.Entry<K,V>>entrySet()Returns aSetview of the mappings contained in this map.VforcePut(K key, V value)An alternate form ofputthat silently removes any existing entry with the valuevaluebefore proceeding with theBiMap.put(K, V)operation.Vget(Object key)Returns the value to which the specified key is mapped, ornullif this map contains no mapping for the key.BiMap<V,K>inverse()Returns the inverse view of this bimap, which maps each of this bimap's values to its associated key.Set<K>keySet()Returns aSetview of the keys contained in this map.Vput(K key, V value)Associates the specified value with the specified key in this map (optional operation).Vremove(Object key)Removes the mapping for a key from this map if it is present (optional operation).intsize()Returns the number of key-value mappings in this map.Set<V>values()Returns aCollectionview of the values contained in this map.- 
Methods inherited from class java.util.AbstractMapclone, equals, hashCode, isEmpty, putAll, toString
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Methods inherited from class java.lang.Objectfinalize, getClass, notify, notifyAll, wait, wait, wait
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Methods inherited from interface java.util.Mapcompute, computeIfAbsent, computeIfPresent, equals, forEach, getOrDefault, hashCode, isEmpty, merge, putIfAbsent, remove, replace, replace, replaceAll
 
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Method Detail- 
createpublic static <K extends @Nullable Object,V extends @Nullable Object> HashBiMap<K,V> create() Returns a new, emptyHashBiMapwith the default initial capacity (16).
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createpublic static <K extends @Nullable Object,V extends @Nullable Object> HashBiMap<K,V> create(int expectedSize) Constructs a new, empty bimap with the specified expected size.- Parameters:
- expectedSize- the expected number of entries
- Throws:
- IllegalArgumentException- if the specified expected size is negative
 
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createpublic static <K extends @Nullable Object,V extends @Nullable Object> HashBiMap<K,V> create(Map<? extends K,? extends V> map) Constructs a new bimap containing initial values frommap. The bimap is created with an initial capacity sufficient to hold the mappings in the specified map.
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sizepublic int size() Description copied from class:java.util.AbstractMapReturns the number of key-value mappings in this map. If the map contains more thanInteger.MAX_VALUEelements, returnsInteger.MAX_VALUE.
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containsKeypublic boolean containsKey(@CheckForNull Object key) Description copied from class:java.util.AbstractMapReturnstrueif this map contains a mapping for the specified key. More formally, returnstrueif and only if this map contains a mapping for a keyksuch thatObjects.equals(key, k). (There can be at most one such mapping.)- Specified by:
- containsKeyin interface- Map<K extends @Nullable Object,V extends @Nullable Object>
- Overrides:
- containsKeyin class- AbstractMap<K extends @Nullable Object,V extends @Nullable Object>
- Parameters:
- key- key whose presence in this map is to be tested
- Returns:
- trueif this map contains a mapping for the specified key
 
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containsValuepublic boolean containsValue(@CheckForNull Object value) Returnstrueif this BiMap contains an entry whose value is equal tovalue(or, equivalently, if this inverse view contains a key that is equal tovalue).Due to the property that values in a BiMap are unique, this will tend to execute in faster-than-linear time. - Specified by:
- containsValuein interface- Map<K extends @Nullable Object,V extends @Nullable Object>
- Overrides:
- containsValuein class- AbstractMap<K extends @Nullable Object,V extends @Nullable Object>
- Parameters:
- value- the object to search for in the values of this BiMap
- Returns:
- true if a mapping exists from a key to the specified value
 
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get@CheckForNull public V get(@CheckForNull Object key) Description copied from class:java.util.AbstractMapReturns the value to which the specified key is mapped, ornullif this map contains no mapping for the key.More formally, if this map contains a mapping from a key kto a valuevsuch thatObjects.equals(key, k), then this method returnsv; otherwise it returnsnull. (There can be at most one such mapping.)If this map permits null values, then a return value of nulldoes not necessarily indicate that the map contains no mapping for the key; it's also possible that the map explicitly maps the key tonull. ThecontainsKeyoperation may be used to distinguish these two cases.- Specified by:
- getin interface- Map<K extends @Nullable Object,V extends @Nullable Object>
- Overrides:
- getin class- AbstractMap<K extends @Nullable Object,V extends @Nullable Object>
- Parameters:
- key- the key whose associated value is to be returned
- Returns:
- the value to which the specified key is mapped, or
         nullif this map contains no mapping for the key
 
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put@CanIgnoreReturnValue @CheckForNull public V put(K key, V value) Description copied from class:java.util.AbstractMapAssociates the specified value with the specified key in this map (optional operation). If the map previously contained a mapping for the key, the old value is replaced by the specified value. (A mapmis said to contain a mapping for a keykif and only ifm.containsKey(k)would returntrue.)- Specified by:
- putin interface- BiMap<K extends @Nullable Object,V extends @Nullable Object>
- Specified by:
- putin interface- Map<K extends @Nullable Object,V extends @Nullable Object>
- Overrides:
- putin class- AbstractMap<K extends @Nullable Object,V extends @Nullable Object>
- Parameters:
- key- key with which the specified value is to be associated
- value- value to be associated with the specified key
- Returns:
- the previous value associated with key, ornullif there was no mapping forkey. (Anullreturn can also indicate that the map previously associatednullwithkey, if the implementation supportsnullvalues.)
 
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forcePut@CanIgnoreReturnValue @CheckForNull public V forcePut(K key, V value) Description copied from interface:BiMapAn alternate form ofputthat silently removes any existing entry with the valuevaluebefore proceeding with theBiMap.put(K, V)operation. If the bimap previously contained the provided key-value mapping, this method has no effect.Note that a successful call to this method could cause the size of the bimap to increase by one, stay the same, or even decrease by one. Warning: If an existing entry with this value is removed, the key for that entry is discarded and not returned. - Specified by:
- forcePutin interface- BiMap<K extends @Nullable Object,V extends @Nullable Object>
- Parameters:
- key- the key with which the specified value is to be associated
- value- the value to be associated with the specified key
- Returns:
- the value that was previously associated with the key, or nullif there was no previous entry. (If the bimap contains null values, thenforcePut, likeput, returnsnullboth if the key is absent and if it is present with a null value.)
 
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remove@CanIgnoreReturnValue @CheckForNull public V remove(@CheckForNull Object key) Description copied from class:java.util.AbstractMapRemoves the mapping for a key from this map if it is present (optional operation). More formally, if this map contains a mapping from keykto valuevsuch thatObjects.equals(key, k), that mapping is removed. (The map can contain at most one such mapping.)Returns the value to which this map previously associated the key, or nullif the map contained no mapping for the key.If this map permits null values, then a return value of nulldoes not necessarily indicate that the map contained no mapping for the key; it's also possible that the map explicitly mapped the key tonull.The map will not contain a mapping for the specified key once the call returns. - Specified by:
- removein interface- Map<K extends @Nullable Object,V extends @Nullable Object>
- Overrides:
- removein class- AbstractMap<K extends @Nullable Object,V extends @Nullable Object>
- Parameters:
- key- key whose mapping is to be removed from the map
- Returns:
- the previous value associated with key, ornullif there was no mapping forkey.
 
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clearpublic void clear() Description copied from class:java.util.AbstractMapRemoves all of the mappings from this map (optional operation). The map will be empty after this call returns.
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keySetpublic Set<K> keySet() Description copied from class:java.util.AbstractMapReturns aSetview of the keys contained in this map. The set is backed by the map, so changes to the map are reflected in the set, and vice-versa. If the map is modified while an iteration over the set is in progress (except through the iterator's ownremoveoperation), the results of the iteration are undefined. The set supports element removal, which removes the corresponding mapping from the map, via theIterator.remove,Set.remove,removeAll,retainAll, andclearoperations. It does not support theaddoraddAlloperations.
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valuespublic Set<V> values() Description copied from class:java.util.AbstractMapReturns aCollectionview of the values contained in this map. The collection is backed by the map, so changes to the map are reflected in the collection, and vice-versa. If the map is modified while an iteration over the collection is in progress (except through the iterator's ownremoveoperation), the results of the iteration are undefined. The collection supports element removal, which removes the corresponding mapping from the map, via theIterator.remove,Collection.remove,removeAll,retainAllandclearoperations. It does not support theaddoraddAlloperations.- Specified by:
- valuesin interface- BiMap<K extends @Nullable Object,V extends @Nullable Object>
- Specified by:
- valuesin interface- Map<K extends @Nullable Object,V extends @Nullable Object>
- Overrides:
- valuesin class- AbstractMap<K extends @Nullable Object,V extends @Nullable Object>
- Returns:
- a collection view of the values contained in this map
 
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entrySetpublic Set<Map.Entry<K,V>> entrySet() Description copied from interface:java.util.MapReturns aSetview of the mappings contained in this map. The set is backed by the map, so changes to the map are reflected in the set, and vice-versa. If the map is modified while an iteration over the set is in progress (except through the iterator's ownremoveoperation, or through thesetValueoperation on a map entry returned by the iterator) the results of the iteration are undefined. The set supports element removal, which removes the corresponding mapping from the map, via theIterator.remove,Set.remove,removeAll,retainAllandclearoperations. It does not support theaddoraddAlloperations.
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inversepublic BiMap<V,K> inverse() Description copied from interface:BiMapReturns the inverse view of this bimap, which maps each of this bimap's values to its associated key. The two bimaps are backed by the same data; any changes to one will appear in the other.Note:There is no guaranteed correspondence between the iteration order of a bimap and that of its inverse. 
 
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