V
 The type of object referred to by this referencepublic class AtomicStampedReference<V> extends Object
AtomicStampedReference
maintains an object reference
along with an integer "stamp", that can be updated atomically.
Implementation note: This implementation maintains stamped references by creating internal objects representing "boxed" [reference, integer] pairs.
Constructor and Description 

AtomicStampedReference(V initialRef,
int initialStamp)
Creates a new
AtomicStampedReference with the given
initial values. 
Modifier and Type  Method and Description 

boolean 
attemptStamp(V expectedReference,
int newStamp)
Atomically sets the value of the stamp to the given update value
if the current reference is
== to the expected
reference. 
boolean 
compareAndSet(V expectedReference,
V newReference,
int expectedStamp,
int newStamp)
Atomically sets the value of both the reference and stamp
to the given update values if the
current reference is
== to the expected reference
and the current stamp is equal to the expected stamp. 
V 
get(int[] stampHolder)
Returns the current values of both the reference and the stamp.

V 
getReference()
Returns the current value of the reference.

int 
getStamp()
Returns the current value of the stamp.

void 
set(V newReference,
int newStamp)
Unconditionally sets the value of both the reference and stamp.

boolean 
weakCompareAndSet(V expectedReference,
V newReference,
int expectedStamp,
int newStamp)
Atomically sets the value of both the reference and stamp
to the given update values if the
current reference is
== to the expected reference
and the current stamp is equal to the expected stamp. 
public AtomicStampedReference(V initialRef, int initialStamp)
AtomicStampedReference
with the given
initial values.initialRef
 the initial referenceinitialStamp
 the initial stamppublic V getReference()
public int getStamp()
public V get(int[] stampHolder)
int[1] holder; ref = v.get(holder);
.stampHolder
 an array of size of at least one. On return,
stampholder[0]
will hold the value of the stamp.public boolean weakCompareAndSet(V expectedReference, V newReference, int expectedStamp, int newStamp)
==
to the expected reference
and the current stamp is equal to the expected stamp.
May fail spuriously
and does not provide ordering guarantees, so is only rarely an
appropriate alternative to compareAndSet
.
expectedReference
 the expected value of the referencenewReference
 the new value for the referenceexpectedStamp
 the expected value of the stampnewStamp
 the new value for the stamppublic boolean compareAndSet(V expectedReference, V newReference, int expectedStamp, int newStamp)
==
to the expected reference
and the current stamp is equal to the expected stamp.expectedReference
 the expected value of the referencenewReference
 the new value for the referenceexpectedStamp
 the expected value of the stampnewStamp
 the new value for the stamppublic void set(V newReference, int newStamp)
newReference
 the new value for the referencenewStamp
 the new value for the stamppublic boolean attemptStamp(V expectedReference, int newStamp)
==
to the expected
reference. Any given invocation of this operation may fail
(return false
) spuriously, but repeated invocation
when the current value holds the expected value and no other
thread is also attempting to set the value will eventually
succeed.expectedReference
 the expected value of the referencenewStamp
 the new value for the stamp