com.google.common.collect

Class EvictingQueue<E>

java.lang.Object

com.google.common.collect.ForwardingObject

com.google.common.collect.ForwardingCollection<E>

com.google.common.collect.ForwardingQueue<E>

com.google.common.collect.EvictingQueue<E>

All Implemented Interfaces:

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

@Beta
 @GwtIncompatible(value="java.util.ArrayDeque")
public final class EvictingQueue<E>
extends ForwardingQueue<E>

A non-blocking queue which automatically evicts elements from the head of the queue when attempting to add new elements onto the queue and it is full.

An evicting queue must be configured with a maximum size. Each time an element is added to a full queue, the queue automatically removes its head element. This is different from conventional bounded queues, which either block or reject new elements when full.

This class is not thread-safe, and does not accept null elements.

Since:

15.0

Method Summary

Modifier and Type	Method and Description
boolean	add(E e) Adds the given element to this queue.
boolean	addAll(Collection<? extends E> collection)
boolean	contains(Object object)
static <E> EvictingQueue<E>	create(int maxSize) Creates and returns a new evicting queue that will hold up to maxSize elements.
boolean	offer(E e) Adds the given element to this queue.
boolean	remove(Object object)

Methods inherited from class com.google.common.collect.ForwardingQueue

element, peek, poll, remove

Methods inherited from class com.google.common.collect.ForwardingCollection

clear, containsAll, isEmpty, iterator, removeAll, retainAll, size, toArray, toArray

Methods inherited from class com.google.common.collect.ForwardingObject

toString

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.util.Collection

clear, containsAll, equals, hashCode, isEmpty, iterator, parallelStream, removeAll, removeIf, retainAll, size, spliterator, stream, toArray, toArray

Methods inherited from interface java.lang.Iterable

forEach

Method Detail

create

public static <E> EvictingQueue<E> create(int maxSize)

Creates and returns a new evicting queue that will hold up to maxSize elements.

When maxSize is zero, elements will be evicted immediately after being added to the queue.

offer

public boolean offer(E e)

Adds the given element to this queue. If the queue is currently full, the element at the head of the queue is evicted to make room.

Specified by:

offer in interface Queue<E>

Overrides:

offer in class ForwardingQueue<E>

Returns:

true always

add

public boolean add(E e)

Adds the given element to this queue. If the queue is currently full, the element at the head of the queue is evicted to make room.

Specified by:

add in interface Collection<E>

Specified by:

add in interface Queue<E>

Overrides:

add in class ForwardingCollection<E>

Returns:

true always

addAll

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

Specified by:

addAll in interface Collection<E>

Overrides:

addAll in class ForwardingCollection<E>

contains

public boolean contains(Object object)

Specified by:

contains in interface Collection<E>

Overrides:

contains in class ForwardingCollection<E>

remove

public boolean remove(Object object)

Specified by:

remove in interface Collection<E>

Overrides:

remove in class ForwardingCollection<E>