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  AtomicStampedReferencewith 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 stamptrue if successfulpublic 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 stamptrue if successfulpublic 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 stamptrue if successful Submit a bug or feature 
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