org.apache.commons.collections4.queue

Class SynchronizedQueue<E>

java.lang.Object

org.apache.commons.collections4.collection.SynchronizedCollection<E>

org.apache.commons.collections4.queue.SynchronizedQueue<E>

Type Parameters:

E - the type of the elements in the collection

All Implemented Interfaces:

java.io.Serializable, java.lang.Iterable<E>, java.util.Collection<E>, java.util.Queue<E>

public class SynchronizedQueue<E>
extends SynchronizedCollection<E>
implements java.util.Queue<E>

Decorates another Queue to synchronize its behaviour for a multi-threaded environment.

Methods are synchronized, then forwarded to the decorated queue. Iterators must be separately synchronized around the loop.

Since:

4.2

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
private static long	serialVersionUID Serialization version

Fields inherited from class org.apache.commons.collections4.collection.SynchronizedCollection

lock

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	SynchronizedQueue(java.util.Queue<E> queue) Constructor that wraps (not copies).
protected	SynchronizedQueue(java.util.Queue<E> queue, java.lang.Object lock) Constructor that wraps (not copies).

Method Summary

Modifier and Type	Method and Description
protected java.util.Queue<E>	decorated() Gets the queue being decorated.
E	element()
boolean	equals(java.lang.Object object)
int	hashCode()
boolean	offer(E e)
E	peek()
E	poll()
E	remove()
static <E> SynchronizedQueue<E>	synchronizedQueue(java.util.Queue<E> queue) Factory method to create a synchronized queue.

Methods inherited from class org.apache.commons.collections4.collection.SynchronizedCollection

add, addAll, clear, contains, containsAll, isEmpty, iterator, remove, removeAll, removeIf, retainAll, size, synchronizedCollection, toArray, toArray, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Queue

add

Methods inherited from interface java.util.Collection

addAll, clear, contains, containsAll, isEmpty, iterator, parallelStream, remove, removeAll, removeIf, retainAll, size, spliterator, stream, toArray, toArray

Methods inherited from interface java.lang.Iterable

forEach

Field Detail

serialVersionUID

private static final long serialVersionUID

Serialization version

See Also:

Constant Field Values

Constructor Detail

SynchronizedQueue

protected SynchronizedQueue(java.util.Queue<E> queue)

Constructor that wraps (not copies).

Parameters:

queue - the queue to decorate, must not be null

Throws:

java.lang.NullPointerException - if queue is null

SynchronizedQueue

protected SynchronizedQueue(java.util.Queue<E> queue,
                            java.lang.Object lock)

Constructor that wraps (not copies).

Parameters:

queue - the queue to decorate, must not be null

lock - the lock to use, must not be null

Throws:

java.lang.NullPointerException - if queue or lock is null

Method Detail

synchronizedQueue

public static <E> SynchronizedQueue<E> synchronizedQueue(java.util.Queue<E> queue)

Factory method to create a synchronized queue.

Type Parameters:

E - the type of the elements in the queue

Parameters:

queue - the queue to decorate, must not be null

Returns:

a new synchronized Queue

Throws:

java.lang.NullPointerException - if queue is null

decorated

protected java.util.Queue<E> decorated()

Gets the queue being decorated.

Overrides:

decorated in class SynchronizedCollection<E>

Returns:

the decorated queue

element

public E element()

Specified by:

element in interface java.util.Queue<E>

equals

public boolean equals(java.lang.Object object)

Specified by:

equals in interface java.util.Collection<E>

Overrides:

equals in class SynchronizedCollection<E>

hashCode

public int hashCode()

Specified by:

hashCode in interface java.util.Collection<E>

Overrides:

hashCode in class SynchronizedCollection<E>

offer

public boolean offer(E e)

Specified by:

offer in interface java.util.Queue<E>

peek

public E peek()

Specified by:

peek in interface java.util.Queue<E>

poll

public E poll()

Specified by:

poll in interface java.util.Queue<E>

remove

public E remove()

Specified by:

remove in interface java.util.Queue<E>