com.rabbitmq.client.impl
Class SetQueue<T>

java.lang.Object
  com.rabbitmq.client.impl.SetQueue<T>

Type Parameters:

T - type of elements in the queue

public class SetQueue<T>
extends java.lang.Object

A generic queue-like implementation (supporting operations addIfNotPresent, poll, contains, and isEmpty) which restricts a queue element to appear at most once. If the element is already present addIfNotPresent(T) returns false.

Elements must not be null.

Concurrent Semantics
This implementation is not thread-safe.

Constructor Summary

SetQueue()

Method Summary

boolean	addIfNotPresent(T item) Add an element to the back of the queue and return true, or else return false.
void	clear() Remove all items from the queue.
boolean	contains(T item)
boolean	isEmpty()
T	poll() Remove the head of the queue and return it.
boolean	remove(T item) Remove item from queue, if present.

Methods inherited from class java.lang.Object

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

Constructor Detail

SetQueue

public SetQueue()

Method Detail

addIfNotPresent

public boolean addIfNotPresent(T item)

Add an element to the back of the queue and return true, or else return false.

Parameters:

item - to add

Returns:

true if the element was added, false if it is already present.

poll

public T poll()

Remove the head of the queue and return it.

Returns:

head element of the queue, or null if the queue is empty.

contains

public boolean contains(T item)

Parameters:

item - to look for in queue

Returns:

true if and only if item is in the queue.

isEmpty

public boolean isEmpty()

Returns:

true if and only if the queue is empty.

remove

public boolean remove(T item)

Remove item from queue, if present.

Parameters:

item - to remove

Returns:

true if and only if item was initially present and was removed.

clear

public void clear()

Remove all items from the queue.