- java.lang.Object
-
- java.util.concurrent.atomic.AtomicStampedReference<V>
-
- Type Parameters:
V
- The type of object referred to by this reference
public class AtomicStampedReference<V> extends Object
AnAtomicStampedReference
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.
- Since:
- 1.5
-
-
Constructor Summary
Constructors Constructor and Description AtomicStampedReference(V initialRef, int initialStamp)
Creates a newAtomicStampedReference
with the given initial values.
-
Method Summary
Methods 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.
-
-
-
Constructor Detail
-
AtomicStampedReference
public AtomicStampedReference(V initialRef, int initialStamp)
Creates a newAtomicStampedReference
with the given initial values.- Parameters:
initialRef
- the initial referenceinitialStamp
- the initial stamp
-
-
Method Detail
-
getReference
public V getReference()
Returns the current value of the reference.- Returns:
- the current value of the reference
-
getStamp
public int getStamp()
Returns the current value of the stamp.- Returns:
- the current value of the stamp
-
get
public V get(int[] stampHolder)
Returns the current values of both the reference and the stamp. Typical usage isint[1] holder; ref = v.get(holder);
.- Parameters:
stampHolder
- an array of size of at least one. On return,stampholder[0]
will hold the value of the stamp.- Returns:
- the current value of the reference
-
weakCompareAndSet
public 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.May fail spuriously and does not provide ordering guarantees, so is only rarely an appropriate alternative to
compareAndSet
.- Parameters:
expectedReference
- the expected value of the referencenewReference
- the new value for the referenceexpectedStamp
- the expected value of the stampnewStamp
- the new value for the stamp- Returns:
- true if successful
-
compareAndSet
public 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.- Parameters:
expectedReference
- the expected value of the referencenewReference
- the new value for the referenceexpectedStamp
- the expected value of the stampnewStamp
- the new value for the stamp- Returns:
- true if successful
-
set
public void set(V newReference, int newStamp)
Unconditionally sets the value of both the reference and stamp.- Parameters:
newReference
- the new value for the referencenewStamp
- the new value for the stamp
-
attemptStamp
public 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. Any given invocation of this operation may fail (returnfalse
) 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.- Parameters:
expectedReference
- the expected value of the referencenewStamp
- the new value for the stamp- Returns:
- true if successful
-
-
Document created the 11/06/2005, last modified the 04/03/2020
Source of the printed document:https://www.gaudry.be/en/java-api-rf-java/util/concurrent/atomic/atomicstampedreference.html
The infobrol is a personal site whose content is my sole responsibility. The text is available under CreativeCommons license (BY-NC-SA). More info on the terms of use and the author.
References
These references and links indicate documents consulted during the writing of this page, or which may provide additional information, but the authors of these sources can not be held responsible for the content of this page.
The author This site is solely responsible for the way in which the various concepts, and the freedoms that are taken with the reference works, are presented here. Remember that you must cross multiple source information to reduce the risk of errors.