/*
* Copyright (c) 2008-2013, Hazelcast, Inc. All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.hazelcast.core;
import java.util.concurrent.
TimeUnit;
/**
*
* Base interface for Hazelcast distributed queues.
*
* @see java.util.concurrent.BlockingQueue
* @see IQueue
* @see TransactionalQueue
* @param <E>
*/
public interface
BaseQueue<E> extends
DistributedObject {
/**
* Inserts the specified element into this queue if it is possible to do
* so immediately without violating capacity restrictions, returning
* <tt>true</tt> upon success and <tt>false</tt> if no space is currently
* available.
*
* @param e the element to add
* @return <tt>true</tt> if the element was added to this queue, else
* <tt>false</tt>
*/
boolean
offer(E
e);
/**
* Inserts the specified element into this queue, waiting up to the
* specified wait time if necessary for space to become available.
*
* @param e the element to add
* @param timeout how long to wait before giving up, in units of
* <tt>unit</tt>
* @param unit a <tt>TimeUnit</tt> determining how to interpret the
* <tt>timeout</tt> parameter
* @return <tt>true</tt> if successful, or <tt>false</tt> if
* the specified waiting time elapses before space is available
* @throws InterruptedException if interrupted while waiting
*/
boolean
offer(E
e, long
timeout,
TimeUnit unit) throws
InterruptedException;
/**
* Retrieves and removes the head of this queue,
* or returns <tt>null</tt> if this queue is empty.
*
* @return the head of this queue, or <tt>null</tt> if this queue is empty
*/
E
poll();
/**
* Retrieves and removes the head of this queue, waiting up to the
* specified wait time if necessary for an element to become available.
*
* @param timeout how long to wait before giving up, in units of
* <tt>unit</tt>
* @param unit a <tt>TimeUnit</tt> determining how to interpret the
* <tt>timeout</tt> parameter
* @return the head of this queue, or <tt>null</tt> if the
* specified waiting time elapses before an element is available
* @throws InterruptedException if interrupted while waiting
*/
E
poll(long
timeout,
TimeUnit unit) throws
InterruptedException;
/**
* Returns the number of elements in this collection. If this collection
* contains more than <tt>Integer.MAX_VALUE</tt> elements, returns
* <tt>Integer.MAX_VALUE</tt>.
*
* @return the number of elements in this collection
*/
int
size();
}