netty5/common/src/main/java/io/netty/util/internal/MpscLinkedQueueHeadRef.java
Norman Maurer b960939ea0 [#4110] Correct javadocs of MpscLinkedQueue
Motivation:

The javadocs are incorrect and so give false impressions of use-pattern.

Modifications:

- Fix javadocs of which operations are allowed from multiple threads concurrently.
- Let isEmpty() work concurrently.

Result:

Correctly document usage-patterns.
2015-08-27 09:09:17 +02:00

55 lines
1.9 KiB
Java

/*
* Copyright 2014 The Netty Project
*
* The Netty Project 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 io.netty.util.internal;
import java.io.Serializable;
import java.util.concurrent.atomic.AtomicReferenceFieldUpdater;
abstract class MpscLinkedQueueHeadRef<E> extends MpscLinkedQueuePad0<E> implements Serializable {
private static final long serialVersionUID = 8467054865577874285L;
@SuppressWarnings("rawtypes")
private static final AtomicReferenceFieldUpdater<MpscLinkedQueueHeadRef, MpscLinkedQueueNode> UPDATER;
static {
@SuppressWarnings("rawtypes")
AtomicReferenceFieldUpdater<MpscLinkedQueueHeadRef, MpscLinkedQueueNode> updater;
updater = PlatformDependent.newAtomicReferenceFieldUpdater(MpscLinkedQueueHeadRef.class, "headRef");
if (updater == null) {
updater = AtomicReferenceFieldUpdater.newUpdater(
MpscLinkedQueueHeadRef.class, MpscLinkedQueueNode.class, "headRef");
}
UPDATER = updater;
}
private transient volatile MpscLinkedQueueNode<E> headRef;
protected final MpscLinkedQueueNode<E> headRef() {
return headRef;
}
protected final void setHeadRef(MpscLinkedQueueNode<E> headRef) {
this.headRef = headRef;
}
protected final void lazySetHeadRef(MpscLinkedQueueNode<E> headRef) {
UPDATER.lazySet(this, headRef);
}
}