Android

java.util.concurrent.atomic.AtomicStampedReference<V>

java.lang.Object
java.util.concurrent.atomic.AtomicStampedReference<V>

An 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.

Summary

Public Constructors

            AtomicStampedReference(V initialRef, int initialStamp)
Creates a new AtomicStampedReference with the given initial values.

Public Methods

          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.
          get(int[] stampHolder)
Returns the current values of both the reference and the stamp.
          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.
Methods inherited from class java.lang.Object

Details

Public Constructors

public AtomicStampedReference(V initialRef, int initialStamp)

Creates a new AtomicStampedReference with the given initial values.

Parameters

initialRef the initial reference
initialStamp the initial stamp

Public Methods

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 (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.

Parameters

expectedReference the expected value of the reference
newStamp the new value for the stamp

Returns

  • true if successful

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 reference
newReference the new value for the reference
expectedStamp the expected value of the stamp
newStamp the new value for the stamp

Returns

  • true if successful

public V get(int[] stampHolder)

Returns the current values of both the reference and the stamp. Typical usage is int[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

public V getReference()

Returns the current value of the reference.

Returns

  • the current value of the reference

public int getStamp()

Returns the current value of the stamp.

Returns

  • the current value of the stamp

public void set(V newReference, int newStamp)

Unconditionally sets the value of both the reference and stamp.

Parameters

newReference the new value for the reference
newStamp the new value for the stamp

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. 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.

Parameters

expectedReference the expected value of the reference
newReference the new value for the reference
expectedStamp the expected value of the stamp
newStamp the new value for the stamp

Returns

  • true if successful
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