/*
 * Copyright (c) 2003, Rafael Steil
 * All rights reserved.

 * Redistribution and use in source and binary forms, 
 * with or without modification, are permitted provided 
 * that the following conditions are met:

 * 1) Redistributions of source code must retain the above 
 * copyright notice, this list of conditions and the 
 * following  disclaimer.
 * 2)  Redistributions in binary form must reproduce the 
 * above copyright notice, this list of conditions and 
 * the following disclaimer in the documentation and/or 
 * other materials provided with the distribution.
 * 3) Neither the name of "Rafael Steil" nor 
 * the names of its contributors may be used to endorse 
 * or promote products derived from this software without 
 * specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT 
 * HOLDERS AND CONTRIBUTORS "AS IS" AND ANY 
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, 
 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR 
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL 
 * THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE 
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES 
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, 
 * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER 
 * IN CONTRACT, STRICT LIABILITY, OR TORT 
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 
 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE
 * 
 * This file creation date: Jan 28, 2004
 * net.jforum.util.concurrent.Queue.java
 * The JForum Project
 * http://www.jforum.net
 * 
 * $Id: Queue.java,v 1.2 2004/04/21 23:57:28 rafaelsteil Exp $
 */
package net.jforum.util.concurrent;

/**
 * Interface for thread-safe queues
 * 
 *@author Rodrigo Kumpera
 */
public interface Queue 
{
	/**
	 * Returns the next object, possibly waiting for an object getting available
	 * */
	Object get() throws InterruptedException;
	
	/**
	 * Try to get the next object waiting for a given timeout
	 * */
	Object pool(long timeout) throws InterruptedException;
	
	/**
	 * Put an object on the queue, possiblt waiting for the queue getting available
	 * */
	void put(Object obj) throws InterruptedException;	
	
	/**
	 * Try to put the object on the queue
	 * */
	boolean offer(Object obj, long timeout) throws InterruptedException;
	
	/**
	 * Itens on this queue.
	 * */
	int size();
}