Package org.agrona.collections
Class Object2IntHashMap<K>
- java.lang.Object
-
- org.agrona.collections.Object2IntHashMap<K>
-
- Type Parameters:
K
- type of keys stored in theMap
- All Implemented Interfaces:
java.util.Map<K,java.lang.Integer>
public class Object2IntHashMap<K> extends java.lang.Object implements java.util.Map<K,java.lang.Integer>
Map
implementation specialised for int values using open addressing and linear probing for cache efficient access. The implementation is mirror copy ofInt2ObjectHashMap
and it also relies on missing value concept fromInt2IntHashMap
.
-
-
Nested Class Summary
Nested Classes Modifier and Type Class Description (package private) class
Object2IntHashMap.AbstractIterator<T>
Base iterator implementation that contains basic logic of traversing the element in the backing array.class
Object2IntHashMap.EntryIterator
Iterator over entries which can provide unboxed access and optionally avoid allocation.class
Object2IntHashMap.EntrySet
Set of entries which can optionally cache iterators to avoid allocation.class
Object2IntHashMap.KeyIterator
Iterator over keys.class
Object2IntHashMap.KeySet
Set of keys that can optionally cache iterators to avoid allocation.class
Object2IntHashMap.ValueCollection
Collection of values which can optionally cache iterators to avoid allocation.class
Object2IntHashMap.ValueIterator
Iterator over values providing unboxed access viaObject2IntHashMap.ValueIterator.nextInt()
.
-
Field Summary
Fields Modifier and Type Field Description private Object2IntHashMap.EntrySet
entrySet
private K[]
keys
private Object2IntHashMap.KeySet
keySet
private float
loadFactor
(package private) static int
MIN_CAPACITY
private int
missingValue
private int
resizeThreshold
private boolean
shouldAvoidAllocation
private int
size
private Object2IntHashMap.ValueCollection
valueCollection
private int[]
values
-
Constructor Summary
Constructors Constructor Description Object2IntHashMap(int missingValue)
Construct a map with default capacity and load factor.Object2IntHashMap(int initialCapacity, float loadFactor, int missingValue)
Construct a new map allowing a configuration for initial capacity and load factor.Object2IntHashMap(int initialCapacity, float loadFactor, int missingValue, boolean shouldAvoidAllocation)
Construct a new map allowing a configuration for initial capacity and load factor.Object2IntHashMap(Object2IntHashMap<K> mapToCopy)
Copy construct a new map from an existing one.
-
Method Summary
All Methods Instance Methods Concrete Methods Modifier and Type Method Description int
capacity()
Get the total capacity for the map to which the load factor will be a fraction of.void
clear()
void
compact()
Compact theMap
backing arrays by rehashing with a capacity just larger than current size and giving consideration to the load factor.private void
compactChain(int deleteIndex)
int
compute(K key, ObjectIntToIntFunction<? super K> remappingFunction)
Attempts to compute a mapping for the specified key and its current mapped value (or missingValue if there is no current mapping).int
computeIfAbsent(K key, java.util.function.ToIntFunction<? super K> mappingFunction)
Get a value for a given key, or if it does not exist then default the value via aIntFunction
and put it in the map.int
computeIfPresent(K key, ObjectIntToIntFunction<? super K> remappingFunction)
If the value for the specified key is present, attempts to compute a new mapping given the key and its current mapped value.boolean
containsKey(java.lang.Object key)
Overloaded version ofMap.containsKey(Object)
that takes a primitive int key.boolean
containsValue(int value)
Overloaded version to avoid boxing.boolean
containsValue(java.lang.Object value)
Object2IntHashMap.EntrySet
entrySet()
boolean
equals(java.lang.Object o)
void
forEach(java.util.function.BiConsumer<? super K,? super java.lang.Integer> action)
void
forEachInt(ObjIntConsumer<? super K> action)
Performs the given action for each entry in this map until all entries have been processed or the action throws an exception.java.lang.Integer
get(java.lang.Object key)
int
getOrDefault(java.lang.Object key, int defaultValue)
Returns the value to which the specified key is mapped, ordefaultValue
if this map contains no mapping for the key.int
getValue(K key)
Overloaded version ofMap.get(Object)
that takes a primitive int key.int
hashCode()
private void
increaseCapacity()
boolean
isEmpty()
Object2IntHashMap.KeySet
keySet()
float
loadFactor()
Get the load factor beyond which the map will increase size.int
merge(K key, int value, IntIntFunction remappingFunction)
If the specified key is not already associated with a value associates it with the given value.int
missingValue()
The value to be used as a null marker in the map.int
put(K key, int value)
Overloaded version ofMap.put(Object, Object)
that takes a primitive int key.java.lang.Integer
put(K key, java.lang.Integer value)
void
putAll(java.util.Map<? extends K,? extends java.lang.Integer> map)
void
putAll(Object2IntHashMap<? extends K> map)
Puts all values from the given map to this map.int
putIfAbsent(K key, int value)
If the specified key is not already associated with a value associates it with the given value and returnsmissingValue()
, else returns the current value.java.lang.Integer
putIfAbsent(K key, java.lang.Integer value)
private void
rehash(int newCapacity)
java.lang.Integer
remove(java.lang.Object key)
boolean
remove(java.lang.Object key, int value)
Primitive overload of theMap.remove(Object, Object)
that avoids boxing on the value.boolean
remove(java.lang.Object key, java.lang.Object value)
int
removeKey(K key)
Overloaded version ofMap.remove(Object)
that takes a key and returns a primitive int value.int
replace(K key, int value)
Primitive specialised version ofMap.replace(Object, Object)
.boolean
replace(K key, int oldValue, int newValue)
Primitive specialised version ofMap.replace(Object, Object, Object)
.void
replaceAllInt(ObjectIntToIntFunction<? super K> function)
Primitive specialised version ofMap.replaceAll(BiFunction)
.int
resizeThreshold()
Get the actual threshold which when reached the map will resize.int
size()
java.lang.String
toString()
private java.lang.Integer
valueOrNull(int value)
Object2IntHashMap.ValueCollection
values()
-
-
-
Field Detail
-
MIN_CAPACITY
static final int MIN_CAPACITY
- See Also:
- Constant Field Values
-
loadFactor
private final float loadFactor
-
missingValue
private final int missingValue
-
resizeThreshold
private int resizeThreshold
-
size
private int size
-
shouldAvoidAllocation
private final boolean shouldAvoidAllocation
-
keys
private K[] keys
-
values
private int[] values
-
valueCollection
private Object2IntHashMap.ValueCollection valueCollection
-
keySet
private Object2IntHashMap.KeySet keySet
-
entrySet
private Object2IntHashMap.EntrySet entrySet
-
-
Constructor Detail
-
Object2IntHashMap
public Object2IntHashMap(int missingValue)
Construct a map with default capacity and load factor.- Parameters:
missingValue
- value to be used as a null maker in the map
-
Object2IntHashMap
public Object2IntHashMap(int initialCapacity, float loadFactor, int missingValue)
Construct a new map allowing a configuration for initial capacity and load factor.- Parameters:
initialCapacity
- for the backing array.loadFactor
- limit for resizing on puts.missingValue
- value to be used as a null marker in the map.
-
Object2IntHashMap
public Object2IntHashMap(int initialCapacity, float loadFactor, int missingValue, boolean shouldAvoidAllocation)
Construct a new map allowing a configuration for initial capacity and load factor.- Parameters:
initialCapacity
- for the backing array.loadFactor
- limit for resizing on puts.missingValue
- value to be used as a null marker in the map.shouldAvoidAllocation
- should allocation be avoided by caching iterators and map entries.
-
Object2IntHashMap
public Object2IntHashMap(Object2IntHashMap<K> mapToCopy)
Copy construct a new map from an existing one.- Parameters:
mapToCopy
- for construction.
-
-
Method Detail
-
missingValue
public int missingValue()
The value to be used as a null marker in the map.- Returns:
- value to be used as a null marker in the map.
-
loadFactor
public float loadFactor()
Get the load factor beyond which the map will increase size.- Returns:
- load factor for when the map should increase size.
-
capacity
public int capacity()
Get the total capacity for the map to which the load factor will be a fraction of.- Returns:
- the total capacity for the map.
-
resizeThreshold
public int resizeThreshold()
Get the actual threshold which when reached the map will resize. This is a function of the current capacity and load factor.- Returns:
- the threshold when the map will resize.
-
size
public int size()
- Specified by:
size
in interfacejava.util.Map<K,java.lang.Integer>
-
isEmpty
public boolean isEmpty()
- Specified by:
isEmpty
in interfacejava.util.Map<K,java.lang.Integer>
-
containsKey
public boolean containsKey(java.lang.Object key)
Overloaded version ofMap.containsKey(Object)
that takes a primitive int key.- Specified by:
containsKey
in interfacejava.util.Map<K,java.lang.Integer>
- Parameters:
key
- for indexing theMap
.- Returns:
- true if the key is found otherwise false.
-
containsValue
public boolean containsValue(java.lang.Object value)
- Specified by:
containsValue
in interfacejava.util.Map<K,java.lang.Integer>
-
containsValue
public boolean containsValue(int value)
Overloaded version to avoid boxing.- Parameters:
value
- to check.- Returns:
- true if the collection contains the value.
-
getOrDefault
public int getOrDefault(java.lang.Object key, int defaultValue)
Returns the value to which the specified key is mapped, ordefaultValue
if this map contains no mapping for the key.- Parameters:
key
- whose associated value is to be returned.defaultValue
- the default mapping of the key.- Returns:
- the value to which the specified key is mapped, or
defaultValue
if this map contains no mapping for the key.
-
get
public java.lang.Integer get(java.lang.Object key)
- Specified by:
get
in interfacejava.util.Map<K,java.lang.Integer>
-
getValue
public int getValue(K key)
Overloaded version ofMap.get(Object)
that takes a primitive int key. Due to type erasure have to rename the method.- Parameters:
key
- for indexing theMap
.- Returns:
- the value if found otherwise missingValue.
-
computeIfAbsent
public int computeIfAbsent(K key, java.util.function.ToIntFunction<? super K> mappingFunction)
Get a value for a given key, or if it does not exist then default the value via aIntFunction
and put it in the map.Primitive specialized version of
Map.computeIfAbsent(K, java.util.function.Function<? super K, ? extends V>)
.- Parameters:
key
- to search on.mappingFunction
- to provide a value if the get returns missingValue.- Returns:
- old value if found otherwise the newly computed value.
-
computeIfPresent
public int computeIfPresent(K key, ObjectIntToIntFunction<? super K> remappingFunction)
If the value for the specified key is present, attempts to compute a new mapping given the key and its current mapped value.If the function returns missingValue, the mapping is removed.
Primitive specialized version of
Map.computeIfPresent(Object, BiFunction)
.- Parameters:
key
- to search on.remappingFunction
- to provide a value if the get returns missingValue.- Returns:
- the new value associated with the specified key, or missingValue if none.
-
compute
public int compute(K key, ObjectIntToIntFunction<? super K> remappingFunction)
Attempts to compute a mapping for the specified key and its current mapped value (or missingValue if there is no current mapping).If the function returns missingValue, the mapping is removed (or remains absent if initially absent).
Primitive specialized version of
Map.compute(Object, BiFunction)
.- Parameters:
key
- to search on.remappingFunction
- to provide a value if the get returns missingValue.- Returns:
- the new value associated with the specified key, or missingValue if none.
-
merge
public int merge(K key, int value, IntIntFunction remappingFunction)
If the specified key is not already associated with a value associates it with the given value. Otherwise, replaces the associated value with the results of the given remapping function, or removes if the result ismissingValue()
. This method may be of use when combining multiple mapped values for a key. If the function returnsmissingValue()
the mapping is removed.Primitive specialized version of
Map.merge(Object, Object, BiFunction)
.- Parameters:
key
- with which the resulting value is to be associated.value
- to be merged with the existing value associated with the key or, if no existing value is associated with the key, to be associated with the key.remappingFunction
- the function to recompute a value if present.- Returns:
- the new value associated with the specified key, or
missingValue()
if no value is associated with the key.
-
put
public java.lang.Integer put(K key, java.lang.Integer value)
- Specified by:
put
in interfacejava.util.Map<K,java.lang.Integer>
-
put
public int put(K key, int value)
Overloaded version ofMap.put(Object, Object)
that takes a primitive int key.- Parameters:
key
- for indexing theMap
.value
- to be inserted in theMap
.- Returns:
- the previous value if found otherwise missingValue.
-
putIfAbsent
public java.lang.Integer putIfAbsent(K key, java.lang.Integer value)
- Specified by:
putIfAbsent
in interfacejava.util.Map<K,java.lang.Integer>
-
putIfAbsent
public int putIfAbsent(K key, int value)
If the specified key is not already associated with a value associates it with the given value and returnsmissingValue()
, else returns the current value.- Parameters:
key
- with which the specified value is to be associated.value
- to be associated with the specified key.- Returns:
- the existing value associated with the specified key, or
missingValue()
if there was no mapping for the key. - Throws:
java.lang.IllegalArgumentException
- ifvalue == missingValue()
-
remove
public boolean remove(java.lang.Object key, java.lang.Object value)
- Specified by:
remove
in interfacejava.util.Map<K,java.lang.Integer>
-
remove
public boolean remove(java.lang.Object key, int value)
Primitive overload of theMap.remove(Object, Object)
that avoids boxing on the value.- Parameters:
key
- with which the specified value is associated.value
- expected to be associated with the specified key.- Returns:
true
if the value was removed.
-
remove
public java.lang.Integer remove(java.lang.Object key)
- Specified by:
remove
in interfacejava.util.Map<K,java.lang.Integer>
-
removeKey
public int removeKey(K key)
Overloaded version ofMap.remove(Object)
that takes a key and returns a primitive int value. Due to type erasure have to rename the method.- Parameters:
key
- for indexing theMap
.- Returns:
- the value if found otherwise missingValue.
-
clear
public void clear()
- Specified by:
clear
in interfacejava.util.Map<K,java.lang.Integer>
-
compact
public void compact()
Compact theMap
backing arrays by rehashing with a capacity just larger than current size and giving consideration to the load factor.
-
putAll
public void putAll(java.util.Map<? extends K,? extends java.lang.Integer> map)
- Specified by:
putAll
in interfacejava.util.Map<K,java.lang.Integer>
-
putAll
public void putAll(Object2IntHashMap<? extends K> map)
Puts all values from the given map to this map.- Parameters:
map
- whose values to be added to this map.
-
keySet
public Object2IntHashMap.KeySet keySet()
- Specified by:
keySet
in interfacejava.util.Map<K,java.lang.Integer>
-
values
public Object2IntHashMap.ValueCollection values()
- Specified by:
values
in interfacejava.util.Map<K,java.lang.Integer>
-
entrySet
public Object2IntHashMap.EntrySet entrySet()
- Specified by:
entrySet
in interfacejava.util.Map<K,java.lang.Integer>
-
toString
public java.lang.String toString()
- Overrides:
toString
in classjava.lang.Object
-
equals
public boolean equals(java.lang.Object o)
- Specified by:
equals
in interfacejava.util.Map<K,java.lang.Integer>
- Overrides:
equals
in classjava.lang.Object
-
hashCode
public int hashCode()
- Specified by:
hashCode
in interfacejava.util.Map<K,java.lang.Integer>
- Overrides:
hashCode
in classjava.lang.Object
-
replace
public int replace(K key, int value)
Primitive specialised version ofMap.replace(Object, Object)
.- Parameters:
key
- with which the specified value is associated.value
- to be associated with the specified key.- Returns:
- the previous value associated with the specified key, or
missingValue()
if there was no mapping for the key.
-
replace
public boolean replace(K key, int oldValue, int newValue)
Primitive specialised version ofMap.replace(Object, Object, Object)
.- Parameters:
key
- key with which the specified value is associated.oldValue
- value expected to be associated with the specified key.newValue
- value to be associated with the specified key.- Returns:
true
if the value was replaced.
-
replaceAllInt
public void replaceAllInt(ObjectIntToIntFunction<? super K> function)
Primitive specialised version ofMap.replaceAll(BiFunction)
.NB: Renamed from replaceAll to avoid overloading on parameter types of lambda expression, which doesn't play well with type inference in lambda expressions.
- Parameters:
function
- the function to apply to each entry.
-
forEach
public void forEach(java.util.function.BiConsumer<? super K,? super java.lang.Integer> action)
- Specified by:
forEach
in interfacejava.util.Map<K,java.lang.Integer>
-
forEachInt
public void forEachInt(ObjIntConsumer<? super K> action)
Performs the given action for each entry in this map until all entries have been processed or the action throws an exception.- Parameters:
action
- to be performed for each entry.
-
increaseCapacity
private void increaseCapacity()
-
rehash
private void rehash(int newCapacity)
-
compactChain
private void compactChain(int deleteIndex)
-
valueOrNull
private java.lang.Integer valueOrNull(int value)
-
-