55 lines
2.0 KiB
Java
55 lines
2.0 KiB
Java
/*
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* Copyright 2014 The Netty Project
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*
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* The Netty Project licenses this file to you under the Apache License,
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* version 2.0 (the "License"); you may not use this file except in compliance
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* with the License. You may obtain a copy of the License at:
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
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* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
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* License for the specific language governing permissions and limitations
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* under the License.
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*/
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package io.netty.util.internal;
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import java.util.concurrent.atomic.AtomicReferenceFieldUpdater;
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abstract class MpscLinkedQueueTailRef<E> extends MpscLinkedQueuePad1<E> {
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private static final long serialVersionUID = 8717072462993327429L;
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@SuppressWarnings("rawtypes")
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private static final AtomicReferenceFieldUpdater<MpscLinkedQueueTailRef, MpscLinkedQueueNode> UPDATER;
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static {
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@SuppressWarnings("rawtypes")
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AtomicReferenceFieldUpdater<MpscLinkedQueueTailRef, MpscLinkedQueueNode> updater;
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updater = PlatformDependent.newAtomicReferenceFieldUpdater(MpscLinkedQueueTailRef.class, "tailRef");
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if (updater == null) {
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updater = AtomicReferenceFieldUpdater.newUpdater(
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MpscLinkedQueueTailRef.class, MpscLinkedQueueNode.class, "tailRef");
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}
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UPDATER = updater;
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}
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private transient volatile MpscLinkedQueueNode<E> tailRef;
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protected final MpscLinkedQueueNode<E> tailRef() {
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return tailRef;
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}
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protected final void setTailRef(MpscLinkedQueueNode<E> tailRef) {
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this.tailRef = tailRef;
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}
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@SuppressWarnings("unchecked")
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protected final MpscLinkedQueueNode<E> getAndSetTailRef(MpscLinkedQueueNode<E> tailRef) {
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// LOCK XCHG in JDK8, a CAS loop in JDK 7/6
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return (MpscLinkedQueueNode<E>) UPDATER.getAndSet(this, tailRef);
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}
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}
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