Package ca.spottedleaf.concurrentutil.map.concurrent.objects

Class ConcurrentChainedReference2ReferenceHashTable<K,V>

java.lang.Object

ca.spottedleaf.concurrentutil.map.concurrent.objects.ConcurrentChainedReference2ReferenceHashTable<K,V>

Type Parameters:

K - The type for keys in this map

V - The type for values in this map

All Implemented Interfaces:

Iterable<ConcurrentChainedReference2ReferenceHashTable.TableEntry<K,V>>

public class ConcurrentChainedReference2ReferenceHashTable<K,V>
extends Object
implements Iterable<ConcurrentChainedReference2ReferenceHashTable.TableEntry<K,V>>

Concurrent hashtable implementation supporting mapping arbitrary non-null K values onto non-null V values with support for multiple writer and multiple reader threads.

Happens-before relationship

As with ConcurrentMap, there is a happens-before relationship between actions in one thread prior to writing to the map and access to the results of those actions in another thread.

Atomicity of functional methods

Functional methods are functions declared in this class which possibly perform a write (remove, replace, or modify) to an entry in this map as a result of invoking a function on an input parameter. Functional methods will be performed atomically, that is, the input parameter is guaranteed to only be invoked at most once per function call. However, the consequence of this behaviour is that a critical lock for a bin entry is held, which means that if the input parameter invocation makes additional calls to write into this hash table that the result is undefined and deadlock-prone.

See Also:

• ConcurrentMap

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	ConcurrentChainedReference2ReferenceHashTable.BiObjectObjectFunction<K,V>
static interface	ConcurrentChainedReference2ReferenceHashTable.BiObjectObjectObjectFunction<P1,P2,R>
protected static final class	ConcurrentChainedReference2ReferenceHashTable.EntryNodeIterator<K,V>
protected static class	ConcurrentChainedReference2ReferenceHashTable.EntrySet<K,V>
protected static final class	ConcurrentChainedReference2ReferenceHashTable.KeyIterator<K,V>
protected static class	ConcurrentChainedReference2ReferenceHashTable.Keys<K>
protected static class	ConcurrentChainedReference2ReferenceHashTable.NodeIterator<K,V>
static interface	ConcurrentChainedReference2ReferenceHashTable.RemoveIfPredicate<K,V>
static final class	ConcurrentChainedReference2ReferenceHashTable.TableEntry<K,V>
protected static final class	ConcurrentChainedReference2ReferenceHashTable.ValueIterator<K,V>
protected static class	ConcurrentChainedReference2ReferenceHashTable.Values<V>

Field Summary

Fields

Modifier and Type	Field	Description
protected static final int	DEFAULT_CAPACITY
protected static final float	DEFAULT_LOAD_FACTOR
protected ConcurrentChainedReference2ReferenceHashTable.EntrySet<K,V>	entrySet
protected ConcurrentChainedReference2ReferenceHashTable.Keys<K>	keys
protected final float	loadFactor
protected static final int	MAXIMUM_CAPACITY
protected ConcurrentChainedReference2ReferenceHashTable.TableEntry<K,V>[]	nextTable
protected final AtomicLong	size
protected ConcurrentChainedReference2ReferenceHashTable.TableEntry<K,V>[]	table
protected int	threshold
protected static final VarHandle	THRESHOLD_HANDLE
protected static final int	THRESHOLD_NO_RESIZE
protected static final int	THRESHOLD_RESIZING
protected ConcurrentChainedReference2ReferenceHashTable.Values<V>	values

Constructor Summary

Constructors

Modifier	Constructor	Description
	ConcurrentChainedReference2ReferenceHashTable()
protected	ConcurrentChainedReference2ReferenceHashTable(int capacity, float loadFactor)

Method Summary

Modifier and Type	Method	Description
protected final void	addSize(long count)	Adds count to size and checks threshold for resizing
void	clear()	Removes at least all entries currently mapped at the beginning of this call.
protected static <K, V> ConcurrentChainedReference2ReferenceHashTable.TableEntry<K,V>	compareAndExchangeAtIndexVolatile(ConcurrentChainedReference2ReferenceHashTable.TableEntry<K,V>[] table, int index, ConcurrentChainedReference2ReferenceHashTable.TableEntry<K,V> expect, ConcurrentChainedReference2ReferenceHashTable.TableEntry<K,V> update)
protected final int	compareExchangeThresholdVolatile(int expect, int update)
V	compute(K key, ConcurrentChainedReference2ReferenceHashTable.BiObjectObjectObjectFunction<K,? super V,? extends V> function)	See ConcurrentMap.compute(Object, BiFunction)
V	computeIfAbsent(K key, ConcurrentChainedReference2ReferenceHashTable.BiObjectObjectFunction<? super K,? extends V> function)	See ConcurrentMap.computeIfAbsent(Object, Function)
V	computeIfPresent(K key, ConcurrentChainedReference2ReferenceHashTable.BiObjectObjectObjectFunction<K,? super V,? extends V> function)	See ConcurrentMap.computeIfPresent(Object, BiFunction)
boolean	contains(K key, V value)	Returns whether the specified key is mapped and is mapped to the specified value.
boolean	containsKey(K key)	Returns whether the specified key is mapped to some value.
boolean	containsValue(V value)	Returns whether the specified value has a key mapped to it.
static <K, V> ConcurrentChainedReference2ReferenceHashTable<K,V>	createWithCapacity(int capacity)
static <K, V> ConcurrentChainedReference2ReferenceHashTable<K,V>	createWithCapacity(int capacity, float loadFactor)
static <K, V> ConcurrentChainedReference2ReferenceHashTable<K,V>	createWithExpected(int expected)
static <K, V> ConcurrentChainedReference2ReferenceHashTable<K,V>	createWithExpected(int expected, float loadFactor)
static int	defaultCapacity()
static float	defaultLoadFactor()
BaseObjectIterator<ConcurrentChainedReference2ReferenceHashTable.TableEntry<K,V>>	entryIterator()	Returns an iterator over the entries in this map.
Set<ConcurrentChainedReference2ReferenceHashTable.TableEntry<K,V>>	entrySet()
protected ConcurrentChainedReference2ReferenceHashTable.TableEntry<K,V>[]	fetchNewTable(ConcurrentChainedReference2ReferenceHashTable.TableEntry<K,V>[] expectedCurr)
V	get(K key)	Returns the currently mapped value associated with the specified key, or null if there is none.
protected static <K, V> ConcurrentChainedReference2ReferenceHashTable.TableEntry<K,V>	getAtIndexAcquire(ConcurrentChainedReference2ReferenceHashTable.TableEntry<K,V>[] table, int index)
protected static int	getCapacityFor(int capacity)
protected static int	getHash(Object key)	must be deterministic given a key
final float	getLoadFactor()	Returns the load factor associated with this map.
protected final ConcurrentChainedReference2ReferenceHashTable.TableEntry<K,V>	getNode(K key)	Returns the possible node associated with the key, or null if there is no such node.
V	getOrDefault(K key, V defaultValue)	Returns the currently mapped value associated with the specified key, or the specified default value if there is none.
protected static int	getTargetThreshold(int capacity, float loadFactor)
protected final int	getThresholdAcquire()
protected final int	getThresholdVolatile()
boolean	isEmpty()	Returns whether this map has no mappings.
final BaseObjectIterator<ConcurrentChainedReference2ReferenceHashTable.TableEntry<K,V>>	iterator()
BaseObjectIterator<K>	keyIterator()	Returns an iterator over the keys in this map.
Set<K>	keys()
V	merge(K key, V def, BiFunction<? super V,? super V,? extends V> function)	See ConcurrentMap.merge(Object, Object, BiFunction)
V	put(K key, V value)	Atomically updates the value associated with key to value, or inserts a new mapping with key mapped to value.
V	putIfAbsent(K key, V value)	Atomically inserts a new mapping with key mapped to value if and only if key is not currently mapped to some value.
V	remove(K key)	Atomically removes the mapping for the specified key and returns the value it was associated with.
V	remove(K key, V expect)	Atomically removes the mapping for the specified key if it is mapped to expect and returns expect.
V	removeIf(K key, ConcurrentChainedReference2ReferenceHashTable.RemoveIfPredicate<K,? super V> predicate)	Atomically removes the mapping for the specified key the predicate returns true for its currently mapped value.
V	replace(K key, V value)	Atomically updates the value associated with key to value, or does nothing if key is not associated with a value.
V	replace(K key, V expect, V update)	Atomically updates the value associated with key to update if the currently associated value is equal to expect, otherwise does nothing.
protected static <K, V> void	setAtIndexRelease(ConcurrentChainedReference2ReferenceHashTable.TableEntry<K,V>[] table, int index, ConcurrentChainedReference2ReferenceHashTable.TableEntry<K,V> value)
protected static <K, V> void	setAtIndexVolatile(ConcurrentChainedReference2ReferenceHashTable.TableEntry<K,V>[] table, int index, ConcurrentChainedReference2ReferenceHashTable.TableEntry<K,V> value)
protected final void	setThresholdPlain(int threshold)
protected final void	setThresholdRelease(int threshold)
protected final void	setThresholdVolatile(int threshold)
int	size()	Returns the number of mappings in this map.
protected final void	subSize(long count)	Subtracts count from size
BaseObjectIterator<V>	valueIterator()	Returns an iterator over the values in this map.
Collection<V>	values()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Field Details

DEFAULT_CAPACITY

protected static final int DEFAULT_CAPACITY

See Also:

• Constant Field Values

DEFAULT_LOAD_FACTOR

protected static final float DEFAULT_LOAD_FACTOR

See Also:

• Constant Field Values

MAXIMUM_CAPACITY

protected static final int MAXIMUM_CAPACITY

See Also:

• Constant Field Values

size

protected final AtomicLong size

loadFactor

protected final float loadFactor

table

protected volatile ConcurrentChainedReference2ReferenceHashTable.TableEntry<K,V>[] table

nextTable

protected volatile ConcurrentChainedReference2ReferenceHashTable.TableEntry<K,V>[] nextTable

THRESHOLD_NO_RESIZE

protected static final int THRESHOLD_NO_RESIZE

See Also:

• Constant Field Values

THRESHOLD_RESIZING

protected static final int THRESHOLD_RESIZING

See Also:

• Constant Field Values

threshold

protected volatile int threshold

THRESHOLD_HANDLE

protected static final VarHandle THRESHOLD_HANDLE

keys

protected ConcurrentChainedReference2ReferenceHashTable.Keys<K> keys

values

protected ConcurrentChainedReference2ReferenceHashTable.Values<V> values

entrySet

protected ConcurrentChainedReference2ReferenceHashTable.EntrySet<K,V> entrySet

Constructor Details

ConcurrentChainedReference2ReferenceHashTable

public ConcurrentChainedReference2ReferenceHashTable()

ConcurrentChainedReference2ReferenceHashTable

protected ConcurrentChainedReference2ReferenceHashTable(int capacity,
 float loadFactor)

Method Details

defaultCapacity

public static int defaultCapacity()

defaultLoadFactor

public static float defaultLoadFactor()

getThresholdAcquire

protected final int getThresholdAcquire()

getThresholdVolatile

protected final int getThresholdVolatile()

setThresholdPlain

protected final void setThresholdPlain(int threshold)

setThresholdRelease

protected final void setThresholdRelease(int threshold)

setThresholdVolatile

protected final void setThresholdVolatile(int threshold)

compareExchangeThresholdVolatile

protected final int compareExchangeThresholdVolatile(int expect,
 int update)

getTargetThreshold

protected static int getTargetThreshold(int capacity,
 float loadFactor)

getCapacityFor

protected static int getCapacityFor(int capacity)

createWithCapacity

public static <K,
V>
ConcurrentChainedReference2ReferenceHashTable<K,V> createWithCapacity(int capacity)

createWithCapacity

public static <K,
V>
ConcurrentChainedReference2ReferenceHashTable<K,V> createWithCapacity(int capacity,
 float loadFactor)

createWithExpected

public static <K,
V>
ConcurrentChainedReference2ReferenceHashTable<K,V> createWithExpected(int expected)

createWithExpected

public static <K,
V>
ConcurrentChainedReference2ReferenceHashTable<K,V> createWithExpected(int expected,
 float loadFactor)

getHash

protected static int getHash(Object key)

must be deterministic given a key

getLoadFactor

public final float getLoadFactor()

Returns the load factor associated with this map.

getAtIndexAcquire

protected static <K,
V>
ConcurrentChainedReference2ReferenceHashTable.TableEntry<K,V> getAtIndexAcquire(ConcurrentChainedReference2ReferenceHashTable.TableEntry<K,V>[] table,
 int index)

setAtIndexRelease

protected static <K,
V> void setAtIndexRelease(ConcurrentChainedReference2ReferenceHashTable.TableEntry<K,V>[] table,
 int index,
 ConcurrentChainedReference2ReferenceHashTable.TableEntry<K,V> value)

setAtIndexVolatile

protected static <K,
V> void setAtIndexVolatile(ConcurrentChainedReference2ReferenceHashTable.TableEntry<K,V>[] table,
 int index,
 ConcurrentChainedReference2ReferenceHashTable.TableEntry<K,V> value)

compareAndExchangeAtIndexVolatile

protected static <K,
V>
ConcurrentChainedReference2ReferenceHashTable.TableEntry<K,V> compareAndExchangeAtIndexVolatile(ConcurrentChainedReference2ReferenceHashTable.TableEntry<K,V>[] table,
 int index,
 ConcurrentChainedReference2ReferenceHashTable.TableEntry<K,V> expect,
 ConcurrentChainedReference2ReferenceHashTable.TableEntry<K,V> update)

fetchNewTable

protected ConcurrentChainedReference2ReferenceHashTable.TableEntry<K,V>[] fetchNewTable(ConcurrentChainedReference2ReferenceHashTable.TableEntry<K,V>[] expectedCurr)

getNode

protected final ConcurrentChainedReference2ReferenceHashTable.TableEntry<K,V> getNode(K key)

Returns the possible node associated with the key, or null if there is no such node. The node returned may have a null ConcurrentChainedReference2ReferenceHashTable.TableEntry.value, in which case the node is a placeholder for a compute/computeIfAbsent call. The placeholder node should not be considered mapped in order to preserve happens-before relationships between writes and reads in the map.

get

public V get(K key)

Returns the currently mapped value associated with the specified key, or null if there is none.

Parameters:

key - Specified key

Throws:

NullPointerException - If key is null

getOrDefault

public V getOrDefault(K key,
 V defaultValue)

Returns the currently mapped value associated with the specified key, or the specified default value if there is none.

Parameters:

key - Specified key

defaultValue - Specified default value

Throws:

NullPointerException - If key is null

containsKey

public boolean containsKey(K key)

Returns whether the specified key is mapped to some value.

Parameters:

key - Specified key

Throws:

NullPointerException - If key is null

containsValue

public boolean containsValue(V value)

Returns whether the specified value has a key mapped to it.

Parameters:

value - Specified value

Throws:

NullPointerException - If value is null

contains

public boolean contains(K key,
 V value)

Returns whether the specified key is mapped and is mapped to the specified value.

Parameters:

key - Specified key

value - Specified value

Throws:

NullPointerException - If key is null

NullPointerException - If value is null

size

public int size()

Returns the number of mappings in this map.

isEmpty

public boolean isEmpty()

Returns whether this map has no mappings.

addSize

protected final void addSize(long count)

Adds count to size and checks threshold for resizing

subSize

protected final void subSize(long count)

Subtracts count from size

put

public V put(K key,
 V value)

Atomically updates the value associated with key to value, or inserts a new mapping with key mapped to value.

Parameters:

key - Specified key

value - Specified value

Returns:

Old value previously associated with key, or null if none.

Throws:

NullPointerException - If key is null

NullPointerException - If value is null

putIfAbsent

public V putIfAbsent(K key,
 V value)

Atomically inserts a new mapping with key mapped to value if and only if key is not currently mapped to some value.

Parameters:

key - Specified key

value - Specified value

Returns:

Value currently associated with key, or null if none and value was associated.

Throws:

NullPointerException - If key is null

NullPointerException - If value is null

replace

public V replace(K key,
 V value)

Atomically updates the value associated with key to value, or does nothing if key is not associated with a value.

Parameters:

key - Specified key

value - Specified value

Returns:

Old value previously associated with key, or null if none.

Throws:

NullPointerException - If key is null

NullPointerException - If value is null

replace

public V replace(K key,
 V expect,
 V update)

Atomically updates the value associated with key to update if the currently associated value is equal to expect, otherwise does nothing.

Parameters:

key - Specified key

expect - Expected value to check current mapped value with

update - Update value to replace mapped value with

Returns:

If the currently mapped value is not equal to expect, then returns the currently mapped value. If the key is not mapped to any value, then returns null. If neither of the two cases are true, then returns expect.

Throws:

NullPointerException - If key is null

NullPointerException - If expect is null

NullPointerException - If update is null

remove

public V remove(K key)

Atomically removes the mapping for the specified key and returns the value it was associated with. If the key is not mapped to a value, then does nothing and returns null.

Parameters:

key - Specified key

Returns:

Old value previously associated with key, or null if none.

Throws:

NullPointerException - If key is null

remove

public V remove(K key,
 V expect)

Atomically removes the mapping for the specified key if it is mapped to expect and returns expect. If the key is not mapped to a value, then does nothing and returns null. If the key is mapped to a value that is not equal to expect, then returns that value.

Parameters:

key - Specified key

expect - Specified expected value

Returns:

The specified expected value if the key was mapped to expect. If the key is not mapped to any value, then returns null. If neither of those cases are true, then returns the current mapped value for key.

Throws:

NullPointerException - If key is null

removeIf

public V removeIf(K key,
 ConcurrentChainedReference2ReferenceHashTable.RemoveIfPredicate<K,? super V> predicate)

Atomically removes the mapping for the specified key the predicate returns true for its currently mapped value. If the key is not mapped to a value, then does nothing and returns null.

This function is a "functional method" as defined by ConcurrentChainedReference2ReferenceHashTable.

Parameters:

key - Specified key

predicate - Specified predicate

Returns:

The specified expected value if the key was mapped to expect. If the key is not mapped to any value, then returns null. If neither of those cases are true, then returns the current (non-null) mapped value for key.

Throws:

NullPointerException - If key is null

NullPointerException - If predicate is null

compute

public V compute(K key,
 ConcurrentChainedReference2ReferenceHashTable.BiObjectObjectObjectFunction<K,? super V,? extends V> function)

See ConcurrentMap.compute(Object, BiFunction)

This function is a "functional method" as defined by ConcurrentChainedReference2ReferenceHashTable.

computeIfAbsent

public V computeIfAbsent(K key,
 ConcurrentChainedReference2ReferenceHashTable.BiObjectObjectFunction<? super K,? extends V> function)

See ConcurrentMap.computeIfAbsent(Object, Function)

This function is a "functional method" as defined by ConcurrentChainedReference2ReferenceHashTable.

computeIfPresent

public V computeIfPresent(K key,
 ConcurrentChainedReference2ReferenceHashTable.BiObjectObjectObjectFunction<K,? super V,? extends V> function)

See ConcurrentMap.computeIfPresent(Object, BiFunction)

This function is a "functional method" as defined by ConcurrentChainedReference2ReferenceHashTable.

merge

public V merge(K key,
 V def,
 BiFunction<? super V,? super V,? extends V> function)

See ConcurrentMap.merge(Object, Object, BiFunction)

This function is a "functional method" as defined by ConcurrentChainedReference2ReferenceHashTable.

clear

public void clear()

Removes at least all entries currently mapped at the beginning of this call. May not remove entries added during this call. As a result, only if this map is not modified during the call, that all entries will be removed by the end of the call.

This function is not atomic.

entryIterator

public BaseObjectIterator<ConcurrentChainedReference2ReferenceHashTable.TableEntry<K,V>> entryIterator()

Returns an iterator over the entries in this map. The iterator is only guaranteed to see entries that were added before the beginning of this call, but it may see entries added during.

iterator

public final BaseObjectIterator<ConcurrentChainedReference2ReferenceHashTable.TableEntry<K,V>> iterator()

Specified by:

iterator in interface Iterable<K>

keyIterator

public BaseObjectIterator<K> keyIterator()

Returns an iterator over the keys in this map. The iterator is only guaranteed to see keys that were added before the beginning of this call, but it may see keys added during.

valueIterator

public BaseObjectIterator<V> valueIterator()

Returns an iterator over the values in this map. The iterator is only guaranteed to see values that were added before the beginning of this call, but it may see values added during.

keys

public Set<K> keys()

values

public Collection<V> values()

entrySet

public Set<ConcurrentChainedReference2ReferenceHashTable.TableEntry<K,V>> entrySet()