Package com.intellij.util.containers

Class UnmodifiableHashMap<K,V>

java.lang.Object

com.intellij.util.containers.UnmodifiableHashMap<K,V>

Type Parameters:

K - type of the map keys

V - type of the map values

All Implemented Interfaces:

java.util.Map<K,V>

public final class UnmodifiableHashMap<K,V>
extends java.lang.Object
implements java.util.Map<K,V>

An immutable unordered hash-based map which optimizes incremental growth and may have custom equals/hashCode strategy. This map doesn't support null keys, but supports null values. This map is not serializable.

Nested Class Summary

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

java.util.Map.Entry<K,V>

Method Summary

Modifier and Type	Method and Description
void	clear() Deprecated. Unsupported operation: this map is immutable. Use empty() to get an empty UnmodifiableHashMap.
boolean	containsKey(java.lang.Object key)
boolean	containsValue(java.lang.Object value)
static <K,V> UnmodifiableHashMap<K,V>	empty() Returns an empty UnmodifiableHashMap with canonical equals/hashCode strategy.
static <K,V> UnmodifiableHashMap<K,V>	empty(<any> strategy) Returns an empty UnmodifiableHashMap with supplied strategy.
java.util.Set<java.util.Map.Entry<K,V>>	entrySet()
boolean	equals(java.lang.Object obj)
void	forEach(java.util.function.BiConsumer<? super K,? super V> action)
static <K,V> UnmodifiableHashMap<K,V>	fromMap(<any> strategy, java.util.Map<? extends K,? extends V> map) Returns an UnmodifiableHashMap which contains all the entries of the supplied map.
static <K,V> UnmodifiableHashMap<K,V>	fromMap(java.util.Map<K,V> map) Returns an UnmodifiableHashMap which contains all the entries of the supplied map.
V	get(java.lang.Object key)
V	getOrDefault(java.lang.Object key, V defaultValue)
int	hashCode()
boolean	isEmpty()
java.util.Set<K>	keySet()
V	put(K key, V value) Deprecated. Unsupported operation: this map is immutable. Use with(Object, Object) to create a new UnmodifiableHashMap with an additional element.
void	putAll(java.util.Map<? extends K,? extends V> m) Deprecated. Unsupported operation: this map is immutable. Use withAll(Map) to create a new UnmodifiableHashMap with additional elements from the specified Map.
V	remove(java.lang.Object key) Deprecated. Unsupported operation: this map is immutable. Use without(Object) to create a new UnmodifiableHashMap without some element.
int	size()
java.lang.String	toString()
java.util.Collection<V>	values()
UnmodifiableHashMap<K,V>	with(K key, V value) Returns an UnmodifiableHashMap which contains all the entries as this map plus the supplied mapping
UnmodifiableHashMap<K,V>	withAll(java.util.Map<? extends K,? extends V> map) Returns an UnmodifiableHashMap which contains all the entries as this map plus all the mappings of the supplied map.
UnmodifiableHashMap<K,V>	without(K key) Returns an UnmodifiableHashMap which contains all the entries as this map except the supplied key.

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Map

compute, computeIfAbsent, computeIfPresent, entry, merge, of, of, of, of, of, of, of, of, of, of, of, ofEntries, putIfAbsent, remove, replace, replace, replaceAll

Method Detail

empty

public static <K,V> UnmodifiableHashMap<K,V> empty()

Returns an empty UnmodifiableHashMap with canonical equals/hashCode strategy.

Type Parameters:

K - type of map keys

V - type of map values

Returns:

an empty UnmodifiableHashMap.

See Also:

TObjectHashingStrategy#CANONICAL

empty

public static <K,V> UnmodifiableHashMap<K,V> empty(<any> strategy)

Returns an empty UnmodifiableHashMap with supplied strategy.

Type Parameters:

K - type of map keys

V - type of map values

Parameters:

strategy - strategy to compare keys

Returns:

an empty UnmodifiableHashMap.

fromMap

public static <K,V> UnmodifiableHashMap<K,V> fromMap(java.util.Map<K,V> map)

Returns an UnmodifiableHashMap which contains all the entries of the supplied map.

Type Parameters:

K - type of map keys

V - type of map values

Parameters:

map - map to copy values from

Returns:

a pre-populated UnmodifiableHashMap. Map return the supplied map if it's already an UnmodifiableHashMap which uses the same equals/hashCode strategy.

fromMap

public static <K,V> UnmodifiableHashMap<K,V> fromMap(<any> strategy,
                                                     java.util.Map<? extends K,? extends V> map)

Returns an UnmodifiableHashMap which contains all the entries of the supplied map. It's assumed that the supplied map remains unchanged during the fromMap call.

Type Parameters:

K - type of map keys

V - type of map values

Parameters:

strategy - strategy to compare keys

map - map to copy values from

Returns:

a pre-populated UnmodifiableHashMap. Map return the supplied map if it's already an UnmodifiableHashMap which uses the same equals/hashCode strategy.

without

public UnmodifiableHashMap<K,V> without(K key)

Returns an UnmodifiableHashMap which contains all the entries as this map except the supplied key.

Parameters:

key - a key to exclude from the result

Returns:

an UnmodifiableHashMap which contains all the entries as this map except the supplied key

with

public UnmodifiableHashMap<K,V> with(K key,
                                     V value)

Returns an UnmodifiableHashMap which contains all the entries as this map plus the supplied mapping

Parameters:

key - a key to add/replace

value - a value to associate with the key

Returns:

an UnmodifiableHashMap which contains all the entries as this map plus the supplied mapping. May return the same map if given key is already associated with the same value. Note however that if value is not the same but equal object, the new map will be created as sometimes it's desired to replace the object with another one which is equal to the old object.

withAll

public UnmodifiableHashMap<K,V> withAll(java.util.Map<? extends K,? extends V> map)

Returns an UnmodifiableHashMap which contains all the entries as this map plus all the mappings of the supplied map.

Parameters:

map - to add entries from

Returns:

an UnmodifiableHashMap which contains all the entries as this map plus all the mappings of the supplied map. May (but not guaranteed) return the same map if the supplied map is empty or all its mappings already exist in this map (assuming values are compared by reference). The equals/hashCode strategy of the resulting map is the same as the strategy of this map.

size

public int size()

Specified by:

size in interface java.util.Map<K,V>

isEmpty

public boolean isEmpty()

Specified by:

isEmpty in interface java.util.Map<K,V>

containsKey

public boolean containsKey(java.lang.Object key)

Specified by:

containsKey in interface java.util.Map<K,V>

containsValue

public boolean containsValue(java.lang.Object value)

Specified by:

containsValue in interface java.util.Map<K,V>

get

public V get(java.lang.Object key)

Specified by:

get in interface java.util.Map<K,V>

getOrDefault

public V getOrDefault(java.lang.Object key,
                      V defaultValue)

Specified by:

getOrDefault in interface java.util.Map<K,V>

hashCode

public int hashCode()

Specified by:

hashCode in interface java.util.Map<K,V>

Overrides:

hashCode in class java.lang.Object

equals

public boolean equals(java.lang.Object obj)

Specified by:

equals in interface java.util.Map<K,V>

Overrides:

equals in class java.lang.Object

put

@Deprecated
public V put(K key,
             V value)

Deprecated. Unsupported operation: this map is immutable. Use with(Object, Object) to create a new UnmodifiableHashMap with an additional element.

Specified by:

put in interface java.util.Map<K,V>

remove

@Deprecated
public V remove(java.lang.Object key)

Deprecated. Unsupported operation: this map is immutable. Use without(Object) to create a new UnmodifiableHashMap without some element.

Specified by:

remove in interface java.util.Map<K,V>

putAll

@Deprecated
public void putAll(java.util.Map<? extends K,? extends V> m)

Deprecated. Unsupported operation: this map is immutable. Use withAll(Map) to create a new UnmodifiableHashMap with additional elements from the specified Map.

Specified by:

putAll in interface java.util.Map<K,V>

clear

@Deprecated
public void clear()

Deprecated. Unsupported operation: this map is immutable. Use empty() to get an empty UnmodifiableHashMap.

Specified by:

clear in interface java.util.Map<K,V>

forEach

public void forEach(java.util.function.BiConsumer<? super K,? super V> action)

Specified by:

forEach in interface java.util.Map<K,V>

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

keySet

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

Specified by:

keySet in interface java.util.Map<K,V>

values

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

Specified by:

values in interface java.util.Map<K,V>

entrySet

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

Specified by:

entrySet in interface java.util.Map<K,V>