| /* |
| * |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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 org.apache.qpid.server.queue; |
| |
| import org.apache.qpid.server.message.ServerMessage; |
| import org.apache.qpid.server.store.MessageEnqueueRecord; |
| |
| import java.util.concurrent.atomic.AtomicReferenceFieldUpdater; |
| |
| public abstract class OrderedQueueEntry extends QueueEntryImpl |
| { |
| static final AtomicReferenceFieldUpdater<OrderedQueueEntry, OrderedQueueEntry> |
| _nextUpdater = |
| AtomicReferenceFieldUpdater.newUpdater |
| (OrderedQueueEntry.class, OrderedQueueEntry.class, "_next"); |
| |
| private volatile OrderedQueueEntry _next; |
| |
| public OrderedQueueEntry(OrderedQueueEntryList queueEntryList) |
| { |
| super(queueEntryList); |
| } |
| |
| public OrderedQueueEntry(OrderedQueueEntryList queueEntryList, |
| ServerMessage message, |
| final MessageEnqueueRecord messageEnqueueRecord) |
| { |
| super(queueEntryList, message, messageEnqueueRecord); |
| } |
| |
| @Override |
| public OrderedQueueEntry getNextNode() |
| { |
| return _next; |
| } |
| |
| @Override |
| public OrderedQueueEntry getNextValidEntry() |
| { |
| |
| OrderedQueueEntry next = getNextNode(); |
| while(next != null && next.isDeleted()) |
| { |
| |
| final OrderedQueueEntry newNext = next.getNextNode(); |
| if(newNext != null) |
| { |
| OrderedQueueEntryList._nextUpdater.compareAndSet(this,next, newNext); |
| next = getNextNode(); |
| } |
| else |
| { |
| next = null; |
| } |
| |
| } |
| return next; |
| } |
| |
| } |