Class HashBiMap<K extends @Nullable Object, V extends @Nullable Object>

java.lang.Object

java.util.AbstractMap<K,V>

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

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

A BiMap backed by two hash tables. This implementation allows null keys and values. A HashBiMap and 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

Nested Class Summary

Nested classes/interfaces inherited from class java.util.AbstractMap

AbstractMap.SimpleEntry<K,V>, AbstractMap.SimpleImmutableEntry<K,V>

Nested classes/interfaces inherited from interface java.util.Map

Map.Entry<K,V>

Method Summary

Modifier and Type	Method	Description
void	clear()
boolean	containsKey(@Nullable Object key)
boolean	containsValue(@Nullable Object value)	Returns true if this BiMap contains an entry whose value is equal to value (or, equivalently, if this inverse view contains a key that is equal to value).
static <K extends @Nullable Object, V extends @Nullable Object> HashBiMap<K,V>	create()	Returns a new, empty HashBiMap with 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 from map.
Set<Map.Entry<K,V>>	entrySet()
@Nullable V	forcePut(K key, V value)	An alternate form of put that silently removes any existing entry with the value value before proceeding with the BiMap.put(K, V) operation.
@Nullable V	get(@Nullable Object 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()
@Nullable V	put(K key, V value)
@Nullable V	remove(@Nullable Object key)
int	size()
Set<V>	values()

Methods inherited from class java.util.AbstractMap

clone, equals, hashCode, isEmpty, putAll, toString

Methods inherited from class java.lang.Object

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

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

putAll

Methods inherited from interface java.util.Map

compute, computeIfAbsent, computeIfPresent, equals, forEach, getOrDefault, hashCode, isEmpty, merge, putIfAbsent, remove, replace, replace, replaceAll

Method Details

create

public static <K extends @Nullable Object, V extends @Nullable Object>
HashBiMap<K,V> create()

Returns a new, empty HashBiMap with the default initial capacity (16).

create

public 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

create

public 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 from map. The bimap is created with an initial capacity sufficient to hold the mappings in the specified map.

size

public int size()

Specified by:

size in interface Map<K extends @Nullable Object, V extends @Nullable Object>

Overrides:

size in class AbstractMap<K extends @Nullable Object, V extends @Nullable Object>

containsKey

public boolean containsKey(@Nullable Object key)

Specified by:

containsKey in interface Map<K extends @Nullable Object, V extends @Nullable Object>

Overrides:

containsKey in class AbstractMap<K extends @Nullable Object, V extends @Nullable Object>

containsValue

public boolean containsValue(@Nullable Object value)

Returns true if this BiMap contains an entry whose value is equal to value (or, equivalently, if this inverse view contains a key that is equal to value).

Due to the property that values in a BiMap are unique, this will tend to execute in faster-than-linear time.

Specified by:

containsValue in interface Map<K extends @Nullable Object, V extends @Nullable Object>

Overrides:

containsValue in 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

get

public @Nullable V get(@Nullable Object key)

Specified by:

get in interface Map<K extends @Nullable Object, V extends @Nullable Object>

Overrides:

get in class AbstractMap<K extends @Nullable Object, V extends @Nullable Object>

put

@CanIgnoreReturnValue
public @Nullable V put(K key,
 V value)

Description copied from interface: BiMap

Specified by:

put in interface BiMap<K extends @Nullable Object, V extends @Nullable Object>

Specified by:

put in interface Map<K extends @Nullable Object, V extends @Nullable Object>

Overrides:

put in class AbstractMap<K extends @Nullable Object, V extends @Nullable Object>

forcePut

@CanIgnoreReturnValue
public @Nullable V forcePut(K key,
 V value)

Description copied from interface: BiMap

An alternate form of put that silently removes any existing entry with the value value before proceeding with the BiMap.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:

forcePut in 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 null if there was no previous entry. (If the bimap contains null values, then forcePut, like put, returns null both if the key is absent and if it is present with a null value.)

remove

@CanIgnoreReturnValue
public @Nullable V remove(@Nullable Object key)

Specified by:

remove in interface Map<K extends @Nullable Object, V extends @Nullable Object>

Overrides:

remove in class AbstractMap<K extends @Nullable Object, V extends @Nullable Object>

clear

public void clear()

Specified by:

clear in interface Map<K extends @Nullable Object, V extends @Nullable Object>

Overrides:

clear in class AbstractMap<K extends @Nullable Object, V extends @Nullable Object>

keySet

public Set<K> keySet()

Specified by:

keySet in interface Map<K extends @Nullable Object, V extends @Nullable Object>

Overrides:

keySet in class AbstractMap<K extends @Nullable Object, V extends @Nullable Object>

values

public Set<V> values()

Description copied from interface: BiMap

Because a bimap has unique values, this method returns a Set, instead of the Collection specified in the Map interface.

Specified by:

values in interface BiMap<K extends @Nullable Object, V extends @Nullable Object>

Specified by:

values in interface Map<K extends @Nullable Object, V extends @Nullable Object>

Overrides:

values in class AbstractMap<K extends @Nullable Object, V extends @Nullable Object>

entrySet

public Set<Map.Entry<K,V>> entrySet()

Specified by:

entrySet in interface Map<K extends @Nullable Object, V extends @Nullable Object>

Specified by:

entrySet in class AbstractMap<K extends @Nullable Object, V extends @Nullable Object>

inverse

public BiMap<V,K> inverse()

Description copied from interface: BiMap

Returns 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.

Specified by:

inverse in interface BiMap<K extends @Nullable Object, V extends @Nullable Object>

Returns:

the inverse view of this bimap