de.weltraumschaf.commons.concurrent

Class ConcurrentQueue<E>

java.lang.Object

de.weltraumschaf.commons.concurrent.ConcurrentQueue<E>

Type Parameters:

E - type of queue entries

All Implemented Interfaces:

Queue<E>

@ThreadSafe
final class ConcurrentQueue<E>
extends Object
implements Queue<E>

Queue implemented with compare-and-set algorithm from Brian Goetz.

Implemented with a linked list.

 
 HEAD    Node_0        Node_1        Node_2        Node_3     TAIL
 null    next->        next->        next->        next->     null
 

Since:

1.0.0

Author:

Sven Strittmatter <weltraumschaf@googlemail.com>

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
private static class	ConcurrentQueue.Entry<T> Linked list entry.

Field Summary

Fields

Modifier and Type	Field and Description
private AtomicReference<ConcurrentQueue.Entry<E>>	head References the head of the linked list.
private AtomicReference<ConcurrentQueue.Entry<E>>	tail References the tail of the linked list.

Constructor Summary

Constructors

Constructor and Description
ConcurrentQueue()

Method Summary

Modifier and Type	Method and Description
void	add(E element) Add element to the tail of queue.
boolean	equals(Object obj)
E	get() Get element from head of queue.
int	hashCode()
boolean	isEmpty() Check if queue is empty.
String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

head

private final AtomicReference<ConcurrentQueue.Entry<E>> head

References the head of the linked list.

tail

private final AtomicReference<ConcurrentQueue.Entry<E>> tail

References the tail of the linked list.

Constructor Detail

ConcurrentQueue

ConcurrentQueue()

Method Detail

isEmpty

public boolean isEmpty()

Description copied from interface: Queue

Check if queue is empty.

Specified by:

isEmpty in interface Queue<E>

Returns:

true if empty; else false

add

public void add(E element)

Description copied from interface: Queue

Add element to the tail of queue.

Specified by:

add in interface Queue<E>

Parameters:

element - added entry

get

public E get()

Description copied from interface: Queue

Get element from head of queue.

Specified by:

get in interface Queue<E>

Returns:

entry first element, null if queue is empty

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object obj)

Overrides:

equals in class Object

toString

public String toString()

Overrides:

toString in class Object