Package org.eclipse.epsilon.common.util

Class SizeCachingConcurrentQueue<E>

java.lang.Object

java.util.AbstractCollection<E>

java.util.AbstractQueue<E>

java.util.concurrent.ConcurrentLinkedQueue<E>

org.eclipse.epsilon.common.util.SizeCachingConcurrentQueue<E>

Type Parameters:

E -

All Implemented Interfaces:

Serializable, Iterable<E>, Collection<E>, Queue<E>

public class SizeCachingConcurrentQueue<E>
extends ConcurrentLinkedQueue<E>

A ConcurrentLinkedQueue wrapper which supports null values using a constant wrapper in place of null elements. This implementation caches the size and updates it when structurally modified to avoid the issue outlined in Java Specialists Issue 261.

Since:

1.6

Author:

Sina Madani

See Also:

• Serialized Form

Field Summary

Fields

Modifier and Type	Field	Description
protected static final Object	NULL
protected final Consumer<? extends E>	offerSuper
protected final AtomicInteger	size

Constructor Summary

Constructors

Constructor	Description
SizeCachingConcurrentQueue()
SizeCachingConcurrentQueue(Collection<? extends E> initial)

Method Summary

Modifier and Type	Method	Description
boolean	addAll(Collection<? extends E> c)
boolean	contains(Object o)
static final <T> T	convertToNull(Object o)
boolean	equals(Object o)
int	hashCode()
Iterator<E>	iterator()
boolean	offer(E e)
E	peek()
E	poll()
boolean	remove(Object o)
protected static final Object	replaceWithNull(Object o)
int	size()

Methods inherited from class java.util.concurrent.ConcurrentLinkedQueue

add, clear, forEach, isEmpty, removeAll, removeIf, retainAll, spliterator, toArray, toArray, toString

Methods inherited from class java.util.AbstractQueue

element, remove

Methods inherited from class java.util.AbstractCollection

containsAll

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Collection

containsAll, parallelStream, stream, toArray

Methods inherited from interface java.util.Queue

element, remove

Field Details

NULL

protected static final Object NULL

size

protected final AtomicInteger size

offerSuper

protected final Consumer<? extends E> offerSuper

Constructor Details

SizeCachingConcurrentQueue

public SizeCachingConcurrentQueue()

SizeCachingConcurrentQueue

public SizeCachingConcurrentQueue(Collection<? extends E> initial)

Method Details

replaceWithNull

protected static final Object replaceWithNull(Object o)

convertToNull

public static final <T> T convertToNull(Object o)

peek

public E peek()

Specified by:

peek in interface Queue<E>

Overrides:

peek in class ConcurrentLinkedQueue<E>

poll

public E poll()

Specified by:

poll in interface Queue<E>

Overrides:

poll in class ConcurrentLinkedQueue<E>

offer

public boolean offer(E e)

Specified by:

offer in interface Queue<E>

Overrides:

offer in class ConcurrentLinkedQueue<E>

addAll

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

Specified by:

addAll in interface Collection<E>

Overrides:

addAll in class ConcurrentLinkedQueue<E>

remove

public boolean remove(Object o)

Specified by:

remove in interface Collection<E>

Overrides:

remove in class ConcurrentLinkedQueue<E>

size

public int size()

Specified by:

size in interface Collection<E>

Overrides:

size in class ConcurrentLinkedQueue<E>

iterator

public Iterator<E> iterator()

Specified by:

iterator in interface Collection<E>

Specified by:

iterator in interface Iterable<E>

Overrides:

iterator in class ConcurrentLinkedQueue<E>

contains

public boolean contains(Object o)

Specified by:

contains in interface Collection<E>

Overrides:

contains in class ConcurrentLinkedQueue<E>

equals

public boolean equals(Object o)

Specified by:

equals in interface Collection<E>

Overrides:

equals in class Object

hashCode

public int hashCode()

Specified by:

hashCode in interface Collection<E>

Overrides:

hashCode in class Object