he <code>updateValue</code> if it
 currently holds the <code>expectedValue</code>, reporting <code>true</code> on
 success.  The classes in this package also contain methods to get and
 unconditionally set values, as well as a weaker conditional atomic
 update operation <code>weakCompareAndSet</code> described below.

 <p>The specifications of these methods enable implementations to
 employ efficient machine-level atomic instructions that are available
 on contemporary processors.  However on some platforms