scala.collection.concurrent.MainNode Maven / Gradle / Ivy
/*
* Scala (https://www.scala-lang.org)
*
* Copyright EPFL and Lightbend, Inc.
*
* Licensed under Apache License 2.0
* (http://www.apache.org/licenses/LICENSE-2.0).
*
* See the NOTICE file distributed with this work for
* additional information regarding copyright ownership.
*/
package scala.collection.concurrent;
import java.lang.Object;
import java.util.concurrent.atomic.AtomicReferenceFieldUpdater;
abstract class MainNode extends BasicNode {
@SuppressWarnings("unchecked")
public static final AtomicReferenceFieldUpdater, MainNode> updater =
AtomicReferenceFieldUpdater.newUpdater((Class>) (Class) MainNode.class, (Class>) (Class) MainNode.class, "prev");
public volatile MainNode prev = null;
public abstract int cachedSize(Object ct);
public boolean CAS_PREV(MainNode oldval, MainNode nval) {
return updater.compareAndSet(this, oldval, nval);
}
public void WRITE_PREV(MainNode nval) {
updater.set(this, nval);
}
// do we need this? unclear in the javadocs...
// apparently not - volatile reads are supposed to be safe
// regardless of whether there are concurrent ARFU updates
@Deprecated @SuppressWarnings("unchecked")
public MainNode READ_PREV() {
return (MainNode) updater.get(this);
}
}