Coverage Report - com.sun.grizzly.connectioncache.spi.concurrent.ConcurrentQueue
 
Classes in this File Line Coverage Branch Coverage Complexity
ConcurrentQueue
N/A
N/A
0
ConcurrentQueue$Handle
N/A
N/A
0
 
 1  
 /*
 2  
  * 
 3  
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 4  
  * 
 5  
  * Copyright 2007-2008 Sun Microsystems, Inc. All rights reserved.
 6  
  * 
 7  
  * The contents of this file are subject to the terms of either the GNU
 8  
  * General Public License Version 2 only ("GPL") or the Common Development
 9  
  * and Distribution License("CDDL") (collectively, the "License").  You
 10  
  * may not use this file except in compliance with the License. You can obtain
 11  
  * a copy of the License at https://glassfish.dev.java.net/public/CDDL+GPL.html
 12  
  * or glassfish/bootstrap/legal/LICENSE.txt.  See the License for the specific
 13  
  * language governing permissions and limitations under the License.
 14  
  * 
 15  
  * When distributing the software, include this License Header Notice in each
 16  
  * file and include the License file at glassfish/bootstrap/legal/LICENSE.txt.
 17  
  * Sun designates this particular file as subject to the "Classpath" exception
 18  
  * as provided by Sun in the GPL Version 2 section of the License file that
 19  
  * accompanied this code.  If applicable, add the following below the License
 20  
  * Header, with the fields enclosed by brackets [] replaced by your own
 21  
  * identifying information: "Portions Copyrighted [year]
 22  
  * [name of copyright owner]"
 23  
  * 
 24  
  * Contributor(s):
 25  
  * 
 26  
  * If you wish your version of this file to be governed by only the CDDL or
 27  
  * only the GPL Version 2, indicate your decision by adding "[Contributor]
 28  
  * elects to include this software in this distribution under the [CDDL or GPL
 29  
  * Version 2] license."  If you don't indicate a single choice of license, a
 30  
  * recipient has the option to distribute your version of this file under
 31  
  * either the CDDL, the GPL Version 2 or to extend the choice of license to
 32  
  * its licensees as provided above.  However, if you add GPL Version 2 code
 33  
  * and therefore, elected the GPL Version 2 license, then the option applies
 34  
  * only if the new code is made subject to such option by the copyright
 35  
  * holder.
 36  
  *
 37  
  */
 38  
 
 39  
 package com.sun.grizzly.connectioncache.spi.concurrent;
 40  
 
 41  
 /** A class that provides a very simply unbounded queue.
 42  
  * The main requirement here is that the class support constant time (very fast)
 43  
  * deletion of arbitrary elements.  An instance of this class must be thread safe,
 44  
  * either by locking or by using a wait-free algorithm (preferred).
 45  
  * The interface is made as simple is possible to make it easier to produce
 46  
  * a wait-free implementation.
 47  
  * @param V  object type to be stored in this <code>ConcurrentQueue</code>
 48  
  */
 49  
 public interface ConcurrentQueue<V> {
 50  
     /** A Handle provides the capability to delete an element of a ConcurrentQueue
 51  
      * very quickly.  Typically, the handle is stored in the element, so that an
 52  
      * element located from another data structure can be quickly deleted from 
 53  
      * a ConcurrentQueue.
 54  
      * @param V  type of {@link Handle}
 55  
      */
 56  
     public interface Handle<V> {
 57  
         /** Return the value that corresponds to this handle.
 58  
          * @return  value that corresponds to this handle
 59  
          */
 60  
         V value() ;
 61  
 
 62  
         /** Delete the element corresponding to this handle 
 63  
          * from the queue.  Takes constant time.  Returns
 64  
          * true if the removal succeeded, or false if it failed.
 65  
          * which can occur if another thread has already called
 66  
          * poll or remove on this element.
 67  
          * @return  true if the removal succeeded, or false if it failed
 68  
          */
 69  
         boolean remove() ;
 70  
     }
 71  
 
 72  
     /** Return the number of elements in the queue.
 73  
      * @return  number of elements in the queue
 74  
      */
 75  
     int size() ;
 76  
 
 77  
     /** Add a new element to the tail of the queue.
 78  
      * Returns a handle for the element in the queue.
 79  
      * @param arg  element to add to the queue
 80  
      * @return  a {@link Handle} for the element added to the queue
 81  
      */
 82  
     Handle<V> offer( V arg ) ;
 83  
 
 84  
     /** Return an element from the head of the queue.
 85  
      * The element is removed from the queue.
 86  
      * @return  element removed from the queue
 87  
      */
 88  
     V poll() ;
 89  
 }