net.greghaines.jesque.utils

Class ConcurrentHashSet<E>

java.lang.Object

net.greghaines.jesque.utils.ConcurrentHashSet<E>

Type Parameters:

E - the type of elements maintained by this set

All Implemented Interfaces:

Iterable<E>, Collection<E>, Set<E>, ConcurrentSet<E>

public class ConcurrentHashSet<E>
extends Object
implements ConcurrentSet<E>

An implementation of ConcurrentSet that is backed by a ConcurrentHashMap.

Author:

Greg Haines

Constructor Summary

Constructors

Constructor and Description
ConcurrentHashSet() Creates a new, empty set with a default initial capacity (16), load factor (0.75) and concurrencyLevel (16).
ConcurrentHashSet(Collection<? extends E> c) Creates a new set with the same entries as the given collection.
ConcurrentHashSet(int initialCapacity) Creates a new, empty set with the specified initial capacity, and with default load factor (0.75) and concurrencyLevel (16).
ConcurrentHashSet(int initialCapacity, float loadFactor) Creates a new, empty set with the specified initial capacity and load factor and with the default concurrencyLevel (16).
ConcurrentHashSet(int initialCapacity, float loadFactor, int concurrencyLevel) Creates a new, empty set with the specified initial capacity, load factor and concurrency level.

Method Summary

Methods

Modifier and Type	Method and Description
boolean	add(E e)
boolean	addAll(Collection<? extends E> c)
void	clear()
boolean	contains(Object o)
boolean	containsAll(Collection<?> c)
boolean	isEmpty()
Iterator<E>	iterator()
boolean	remove(Object o)
boolean	removeAll(Collection<?> c)
boolean	retainAll(Collection<?> c)
int	size()
Object[]	toArray()
<T> T[]	toArray(T[] a)

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Set

equals, hashCode

Constructor Detail

ConcurrentHashSet

public ConcurrentHashSet()

Creates a new, empty set with a default initial capacity (16), load factor (0.75) and concurrencyLevel (16).

ConcurrentHashSet

public ConcurrentHashSet(int initialCapacity)

Creates a new, empty set with the specified initial capacity, and with default load factor (0.75) and concurrencyLevel (16).

Parameters:

initialCapacity - the initial capacity. The implementation performs internal sizing to accommodate this many elements.

ConcurrentHashSet

public ConcurrentHashSet(int initialCapacity,
                 float loadFactor)

Creates a new, empty set with the specified initial capacity and load factor and with the default concurrencyLevel (16).

Parameters:

initialCapacity - the initial capacity. The implementation performs internal sizing to accommodate this many elements.

loadFactor - the load factor threshold, used to control resizing. Resizing may be performed when the average number of elements per bin exceeds this threshold.

ConcurrentHashSet

public ConcurrentHashSet(int initialCapacity,
                 float loadFactor,
                 int concurrencyLevel)

Creates a new, empty set with the specified initial capacity, load factor and concurrency level.

Parameters:

initialCapacity - the initial capacity. The implementation performs internal sizing to accommodate this many elements.

loadFactor - the load factor threshold, used to control resizing. Resizing may be performed when the average number of elements per bin exceeds this threshold.

concurrencyLevel - the estimated number of concurrently updating threads. The implementation performs internal sizing to try to accommodate this many threads.

ConcurrentHashSet

public ConcurrentHashSet(Collection<? extends E> c)

Creates a new set with the same entries as the given collection. The set is created with a capacity of 1.5 times the number of entries in the given collection or 16 (whichever is greater), and a default load factor (0.75) and concurrencyLevel (16).

Parameters:

c - the collection

Method Detail

size

public int size()

Specified by:

size in interface Collection<E>

Specified by:

size in interface Set<E>

isEmpty

public boolean isEmpty()

Specified by:

isEmpty in interface Collection<E>

Specified by:

isEmpty in interface Set<E>

contains

public boolean contains(Object o)

Specified by:

contains in interface Collection<E>

Specified by:

contains in interface Set<E>

iterator

public Iterator<E> iterator()

Specified by:

iterator in interface Iterable<E>

Specified by:

iterator in interface Collection<E>

Specified by:

iterator in interface Set<E>

toArray

public Object[] toArray()

Specified by:

toArray in interface Collection<E>

Specified by:

toArray in interface Set<E>

toArray

public <T> T[] toArray(T[] a)

Specified by:

toArray in interface Collection<E>

Specified by:

toArray in interface Set<E>

add

public boolean add(E e)

Specified by:

add in interface Collection<E>

Specified by:

add in interface Set<E>

remove

public boolean remove(Object o)

Specified by:

remove in interface Collection<E>

Specified by:

remove in interface Set<E>

containsAll

public boolean containsAll(Collection<?> c)

Specified by:

containsAll in interface Collection<E>

Specified by:

containsAll in interface Set<E>

addAll

public boolean addAll(Collection<? extends E> c)

Specified by:

addAll in interface Collection<E>

Specified by:

addAll in interface Set<E>

retainAll

public boolean retainAll(Collection<?> c)

Specified by:

retainAll in interface Collection<E>

Specified by:

retainAll in interface Set<E>

removeAll

public boolean removeAll(Collection<?> c)

Specified by:

removeAll in interface Collection<E>

Specified by:

removeAll in interface Set<E>

clear

public void clear()

Specified by:

clear in interface Collection<E>

Specified by:

clear in interface Set<E>