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/* __ *\
** ________ ___ / / ___ Scala API **
** / __/ __// _ | / / / _ | (c) 2003-2012, LAMP/EPFL **
** __\ \/ /__/ __ |/ /__/ __ | http://scala-lang.org/ **
** /____/\___/_/ |_/____/_/ | | **
** |/ **
\* */
package scala.collection.concurrent;
import java.util.concurrent.atomic.AtomicReferenceFieldUpdater;
abstract class MainNode<K, V> extends BasicNode {
public static final AtomicReferenceFieldUpdater<MainNode, MainNode> updater = AtomicReferenceFieldUpdater.newUpdater(MainNode.class, MainNode.class, "prev");
public volatile MainNode<K, V> prev = null;
public abstract int cachedSize(Object ct);
public boolean CAS_PREV(MainNode<K, V> oldval, MainNode<K, V> nval) {
return updater.compareAndSet(this, oldval, nval);
}
public void WRITE_PREV(MainNode<K, V> nval) {
updater.set(this, nval);
}
// do we need this? unclear in the javadocs...
// apparently not - volatile reads are supposed to be safe
// irregardless of whether there are concurrent ARFU updates
public MainNode<K, V> READ_PREV() {
return updater.get(this);
}
}
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