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/* __ *\
** ________ ___ / / ___ Scala API **
** / __/ __// _ | / / / _ | (c) 2003-2013, LAMP/EPFL **
** __\ \/ /__/ __ |/ /__/ __ | http://scala-lang.org/ **
** /____/\___/_/ |_/____/_/ | | **
** |/ **
\* */
package scala.concurrent.impl;
import scala.concurrent.util.Unsafe;
import java.util.concurrent.atomic.AtomicReferenceFieldUpdater;
abstract class AbstractPromise {
private volatile Object _ref;
final static long _refoffset;
static {
try {
_refoffset = Unsafe.instance.objectFieldOffset(AbstractPromise.class.getDeclaredField("_ref"));
} catch (Throwable t) {
throw new ExceptionInInitializerError(t);
}
}
protected final boolean updateState(Object oldState, Object newState) {
return Unsafe.instance.compareAndSwapObject(this, _refoffset, oldState, newState);
}
protected final Object getState() {
return _ref;
}
protected final static AtomicReferenceFieldUpdater<AbstractPromise, Object> updater =
AtomicReferenceFieldUpdater.newUpdater(AbstractPromise.class, Object.class, "_ref");
}
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