# AtomicReference Added in[API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) Summary:[Ctors](https://developer.android.com/reference/java/util/concurrent/atomic/AtomicReference#pubctors)\|[Methods](https://developer.android.com/reference/java/util/concurrent/atomic/AtomicReference#pubmethods)\|[Inherited Methods](https://developer.android.com/reference/java/util/concurrent/atomic/AtomicReference#inhmethods) # AtomicReference ` public class AtomicReference ` ` extends `[Object](https://developer.android.com/reference/java/lang/Object)` `` implements `[Serializable](https://developer.android.com/reference/java/io/Serializable)` ` |---|--------------------------------------------------| | [java.lang.Object](https://developer.android.com/reference/java/lang/Object) || | ↳ | java.util.concurrent.atomic.AtomicReference\ |
*** ** * ** *** An object reference that may be updated atomically. See the[VarHandle](https://developer.android.com/reference/java/lang/invoke/VarHandle)specification for descriptions of the properties of atomic accesses. ## Summary | ### Public constructors || |-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---| | ` `[AtomicReference](https://developer.android.com/reference/java/util/concurrent/atomic/AtomicReference#AtomicReference())`() ` Creates a new AtomicReference with null initial value. | | ` `[AtomicReference](https://developer.android.com/reference/java/util/concurrent/atomic/AtomicReference#AtomicReference(V))`(V initialValue) ` Creates a new AtomicReference with the given initial value. | | ### Public methods || |-----------------------------------------------------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| | ` final V` | ` `[accumulateAndGet](https://developer.android.com/reference/java/util/concurrent/atomic/AtomicReference#accumulateAndGet(V,%20java.util.function.BinaryOperator))`(V x, `[BinaryOperator](https://developer.android.com/reference/java/util/function/BinaryOperator)` accumulatorFunction) ` Atomically updates (with memory effects as specified by[VarHandle.compareAndSet(Object)](https://developer.android.com/reference/java/lang/invoke/VarHandle#compareAndSet(java.lang.Object[]))) the current value with the results of applying the given function to the current and given values, returning the updated value. | | ` final V` | ` `[compareAndExchange](https://developer.android.com/reference/java/util/concurrent/atomic/AtomicReference#compareAndExchange(V,%20V))`(V expectedValue, V newValue) ` Atomically sets the value to`newValue`if the current value, referred to as the*witness value* ,`== expectedValue`, with memory effects as specified by[VarHandle.compareAndExchange](https://developer.android.com/reference/java/lang/invoke/VarHandle#compareAndExchange(java.lang.Object[])). | | ` final V` | ` `[compareAndExchangeAcquire](https://developer.android.com/reference/java/util/concurrent/atomic/AtomicReference#compareAndExchangeAcquire(V,%20V))`(V expectedValue, V newValue) ` Atomically sets the value to`newValue`if the current value, referred to as the*witness value* ,`== expectedValue`, with memory effects as specified by[VarHandle.compareAndExchangeAcquire](https://developer.android.com/reference/java/lang/invoke/VarHandle#compareAndExchangeAcquire(java.lang.Object[])). | | ` final V` | ` `[compareAndExchangeRelease](https://developer.android.com/reference/java/util/concurrent/atomic/AtomicReference#compareAndExchangeRelease(V,%20V))`(V expectedValue, V newValue) ` Atomically sets the value to`newValue`if the current value, referred to as the*witness value* ,`== expectedValue`, with memory effects as specified by[VarHandle.compareAndExchangeRelease](https://developer.android.com/reference/java/lang/invoke/VarHandle#compareAndExchangeRelease(java.lang.Object[])). | | ` final boolean` | ` `[compareAndSet](https://developer.android.com/reference/java/util/concurrent/atomic/AtomicReference#compareAndSet(V,%20V))`(V expectedValue, V newValue) ` Atomically sets the value to`newValue`if the current value`== expectedValue`, with memory effects as specified by[VarHandle.compareAndSet](https://developer.android.com/reference/java/lang/invoke/VarHandle#compareAndSet(java.lang.Object[])). | | ` final V` | ` `[get](https://developer.android.com/reference/java/util/concurrent/atomic/AtomicReference#get())`() ` Returns the current value, with memory effects as specified by[VarHandle.getVolatile](https://developer.android.com/reference/java/lang/invoke/VarHandle#getVolatile(java.lang.Object[])). | | ` final V` | ` `[getAcquire](https://developer.android.com/reference/java/util/concurrent/atomic/AtomicReference#getAcquire())`() ` Returns the current value, with memory effects as specified by[VarHandle.getAcquire](https://developer.android.com/reference/java/lang/invoke/VarHandle#getAcquire(java.lang.Object[])). | | ` final V` | ` `[getAndAccumulate](https://developer.android.com/reference/java/util/concurrent/atomic/AtomicReference#getAndAccumulate(V,%20java.util.function.BinaryOperator))`(V x, `[BinaryOperator](https://developer.android.com/reference/java/util/function/BinaryOperator)` accumulatorFunction) ` Atomically updates (with memory effects as specified by[VarHandle.compareAndSet(Object)](https://developer.android.com/reference/java/lang/invoke/VarHandle#compareAndSet(java.lang.Object[]))) the current value with the results of applying the given function to the current and given values, returning the previous value. | | ` final V` | ` `[getAndSet](https://developer.android.com/reference/java/util/concurrent/atomic/AtomicReference#getAndSet(V))`(V newValue) ` Atomically sets the value to`newValue`and returns the old value, with memory effects as specified by[VarHandle.getAndSet](https://developer.android.com/reference/java/lang/invoke/VarHandle#getAndSet(java.lang.Object[])). | | ` final V` | ` `[getAndUpdate](https://developer.android.com/reference/java/util/concurrent/atomic/AtomicReference#getAndUpdate(java.util.function.UnaryOperator))`(`[UnaryOperator](https://developer.android.com/reference/java/util/function/UnaryOperator)` updateFunction) ` Atomically updates (with memory effects as specified by[VarHandle.compareAndSet(Object)](https://developer.android.com/reference/java/lang/invoke/VarHandle#compareAndSet(java.lang.Object[]))) the current value with the results of applying the given function, returning the previous value. | | ` final V` | ` `[getOpaque](https://developer.android.com/reference/java/util/concurrent/atomic/AtomicReference#getOpaque())`() ` Returns the current value, with memory effects as specified by[VarHandle.getOpaque](https://developer.android.com/reference/java/lang/invoke/VarHandle#getOpaque(java.lang.Object[])). | | ` final V` | ` `[getPlain](https://developer.android.com/reference/java/util/concurrent/atomic/AtomicReference#getPlain())`() ` Returns the current value, with memory semantics of reading as if the variable was declared non-`volatile`. | | ` final void` | ` `[lazySet](https://developer.android.com/reference/java/util/concurrent/atomic/AtomicReference#lazySet(V))`(V newValue) ` Sets the value to`newValue`, with memory effects as specified by[VarHandle.setRelease](https://developer.android.com/reference/java/lang/invoke/VarHandle#setRelease(java.lang.Object[])). | | ` final void` | ` `[set](https://developer.android.com/reference/java/util/concurrent/atomic/AtomicReference#set(V))`(V newValue) ` Sets the value to`newValue`, with memory effects as specified by[VarHandle.setVolatile](https://developer.android.com/reference/java/lang/invoke/VarHandle#setVolatile(java.lang.Object[])). | | ` final void` | ` `[setOpaque](https://developer.android.com/reference/java/util/concurrent/atomic/AtomicReference#setOpaque(V))`(V newValue) ` Sets the value to`newValue`, with memory effects as specified by[VarHandle.setOpaque](https://developer.android.com/reference/java/lang/invoke/VarHandle#setOpaque(java.lang.Object[])). | | ` final void` | ` `[setPlain](https://developer.android.com/reference/java/util/concurrent/atomic/AtomicReference#setPlain(V))`(V newValue) ` Sets the value to`newValue`, with memory semantics of setting as if the variable was declared non-`volatile`and non-`final`. | | ` final void` | ` `[setRelease](https://developer.android.com/reference/java/util/concurrent/atomic/AtomicReference#setRelease(V))`(V newValue) ` Sets the value to`newValue`, with memory effects as specified by[VarHandle.setRelease](https://developer.android.com/reference/java/lang/invoke/VarHandle#setRelease(java.lang.Object[])). | | ` `[String](https://developer.android.com/reference/java/lang/String) | ` `[toString](https://developer.android.com/reference/java/util/concurrent/atomic/AtomicReference#toString())`() ` Returns the String representation of the current value. | | ` final V` | ` `[updateAndGet](https://developer.android.com/reference/java/util/concurrent/atomic/AtomicReference#updateAndGet(java.util.function.UnaryOperator))`(`[UnaryOperator](https://developer.android.com/reference/java/util/function/UnaryOperator)` updateFunction) ` Atomically updates (with memory effects as specified by[VarHandle.compareAndSet(Object)](https://developer.android.com/reference/java/lang/invoke/VarHandle#compareAndSet(java.lang.Object[]))) the current value with the results of applying the given function, returning the updated value. | | ` final boolean` | ` `[weakCompareAndSet](https://developer.android.com/reference/java/util/concurrent/atomic/AtomicReference#weakCompareAndSet(V,%20V))`(V expectedValue, V newValue) ` *This method was deprecated in API level 33. This method has plain memory effects but the method name implies volatile memory effects (see methods such as[compareAndExchange(V, V)](https://developer.android.com/reference/java/util/concurrent/atomic/AtomicReference#compareAndExchange(V,%20V))and[compareAndSet(V, V)](https://developer.android.com/reference/java/util/concurrent/atomic/AtomicReference#compareAndSet(V,%20V))). To avoid confusion over plain or volatile memory effects it is recommended that the method[weakCompareAndSetPlain(V, V)](https://developer.android.com/reference/java/util/concurrent/atomic/AtomicReference#weakCompareAndSetPlain(V,%20V))be used instead.* | | ` final boolean` | ` `[weakCompareAndSetAcquire](https://developer.android.com/reference/java/util/concurrent/atomic/AtomicReference#weakCompareAndSetAcquire(V,%20V))`(V expectedValue, V newValue) ` Possibly atomically sets the value to`newValue`if the current value`== expectedValue`, with memory effects as specified by[VarHandle.weakCompareAndSetAcquire](https://developer.android.com/reference/java/lang/invoke/VarHandle#weakCompareAndSetAcquire(java.lang.Object[])). | | ` final boolean` | ` `[weakCompareAndSetPlain](https://developer.android.com/reference/java/util/concurrent/atomic/AtomicReference#weakCompareAndSetPlain(V,%20V))`(V expectedValue, V newValue) ` Possibly atomically sets the value to`newValue`if the current value`== expectedValue`, with memory effects as specified by[VarHandle.weakCompareAndSetPlain](https://developer.android.com/reference/java/lang/invoke/VarHandle#weakCompareAndSetPlain(java.lang.Object[])). | | ` final boolean` | ` `[weakCompareAndSetRelease](https://developer.android.com/reference/java/util/concurrent/atomic/AtomicReference#weakCompareAndSetRelease(V,%20V))`(V expectedValue, V newValue) ` Possibly atomically sets the value to`newValue`if the current value`== expectedValue`, with memory effects as specified by[VarHandle.weakCompareAndSetRelease](https://developer.android.com/reference/java/lang/invoke/VarHandle#weakCompareAndSetRelease(java.lang.Object[])). | | ` final boolean` | ` `[weakCompareAndSetVolatile](https://developer.android.com/reference/java/util/concurrent/atomic/AtomicReference#weakCompareAndSetVolatile(V,%20V))`(V expectedValue, V newValue) ` Possibly atomically sets the value to`newValue`if the current value`== expectedValue`, with memory effects as specified by[VarHandle.weakCompareAndSet](https://developer.android.com/reference/java/lang/invoke/VarHandle#weakCompareAndSet(java.lang.Object[])). | | ### Inherited methods | |-----------------------|---| | From class` `[java.lang.Object](https://developer.android.com/reference/java/lang/Object)` ` |--------------------------------------------------------------------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| | ` `[Object](https://developer.android.com/reference/java/lang/Object) | ` `[clone](https://developer.android.com/reference/java/lang/Object#clone())`() ` Creates and returns a copy of this object. | | ` boolean` | ` `[equals](https://developer.android.com/reference/java/lang/Object#equals(java.lang.Object))`(`[Object](https://developer.android.com/reference/java/lang/Object)` obj) ` Indicates whether some other object is "equal to" this one. | | ` void` | ` `[finalize](https://developer.android.com/reference/java/lang/Object#finalize())`() ` Called by the garbage collector on an object when garbage collection determines that there are no more references to the object. | | ` final `[Class](https://developer.android.com/reference/java/lang/Class)`` | ` `[getClass](https://developer.android.com/reference/java/lang/Object#getClass())`() ` Returns the runtime class of this`Object`. | | ` int` | ` `[hashCode](https://developer.android.com/reference/java/lang/Object#hashCode())`() ` Returns a hash code value for the object. | | ` final void` | ` `[notify](https://developer.android.com/reference/java/lang/Object#notify())`() ` Wakes up a single thread that is waiting on this object's monitor. | | ` final void` | ` `[notifyAll](https://developer.android.com/reference/java/lang/Object#notifyAll())`() ` Wakes up all threads that are waiting on this object's monitor. | | ` `[String](https://developer.android.com/reference/java/lang/String) | ` `[toString](https://developer.android.com/reference/java/lang/Object#toString())`() ` Returns a string representation of the object. | | ` final void` | ` `[wait](https://developer.android.com/reference/java/lang/Object#wait(long,%20int))`(long timeoutMillis, int nanos) ` Causes the current thread to wait until it is awakened, typically by being*notified* or*interrupted*, or until a certain amount of real time has elapsed. | | ` final void` | ` `[wait](https://developer.android.com/reference/java/lang/Object#wait(long))`(long timeoutMillis) ` Causes the current thread to wait until it is awakened, typically by being*notified* or*interrupted*, or until a certain amount of real time has elapsed. | | ` final void` | ` `[wait](https://developer.android.com/reference/java/lang/Object#wait())`() ` Causes the current thread to wait until it is awakened, typically by being*notified* or*interrupted*. | || ## Public constructors ### AtomicReference Added in[API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public AtomicReference () ``` Creates a new AtomicReference with null initial value.
### AtomicReference Added in[API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public AtomicReference (V initialValue) ``` Creates a new AtomicReference with the given initial value.
| Parameters || |----------------|-------------------------------| | `initialValue` | `V`: the initial value
| ## Public methods ### accumulateAndGet Added in[API level 24](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public final V accumulateAndGet (V x, BinaryOperator accumulatorFunction) ``` Atomically updates (with memory effects as specified by[VarHandle.compareAndSet(Object)](https://developer.android.com/reference/java/lang/invoke/VarHandle#compareAndSet(java.lang.Object[]))) the current value with the results of applying the given function to the current and given values, returning the updated value. The function should be side-effect-free, since it may be re-applied when attempted updates fail due to contention among threads. The function is applied with the current value as its first argument, and the given update as the second argument.
| Parameters || |-----------------------|-----------------------------------------------------------------------| | `x` | `V`: the update value
| | `accumulatorFunction` | `BinaryOperator`: a side-effect-free function of two arguments
| | Returns || |-----|--------------------------| | `V` | the updated value
| ### compareAndExchange Added in[API level 33](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public final V compareAndExchange (V expectedValue, V newValue) ``` Atomically sets the value to`newValue`if the current value, referred to as the*witness value* ,`== expectedValue`, with memory effects as specified by[VarHandle.compareAndExchange](https://developer.android.com/reference/java/lang/invoke/VarHandle#compareAndExchange(java.lang.Object[])).
| Parameters || |-----------------|--------------------------------| | `expectedValue` | `V`: the expected value
| | `newValue` | `V`: the new value
| | Returns || |-----|----------------------------------------------------------------------------------------| | `V` | the*witness value* , which will be the same as the expected value if successful
| ### compareAndExchangeAcquire Added in[API level 33](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public final V compareAndExchangeAcquire (V expectedValue, V newValue) ``` Atomically sets the value to`newValue`if the current value, referred to as the*witness value* ,`== expectedValue`, with memory effects as specified by[VarHandle.compareAndExchangeAcquire](https://developer.android.com/reference/java/lang/invoke/VarHandle#compareAndExchangeAcquire(java.lang.Object[])).
| Parameters || |-----------------|--------------------------------| | `expectedValue` | `V`: the expected value
| | `newValue` | `V`: the new value
| | Returns || |-----|----------------------------------------------------------------------------------------| | `V` | the*witness value* , which will be the same as the expected value if successful
| ### compareAndExchangeRelease Added in[API level 33](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public final V compareAndExchangeRelease (V expectedValue, V newValue) ``` Atomically sets the value to`newValue`if the current value, referred to as the*witness value* ,`== expectedValue`, with memory effects as specified by[VarHandle.compareAndExchangeRelease](https://developer.android.com/reference/java/lang/invoke/VarHandle#compareAndExchangeRelease(java.lang.Object[])).
| Parameters || |-----------------|--------------------------------| | `expectedValue` | `V`: the expected value
| | `newValue` | `V`: the new value
| | Returns || |-----|----------------------------------------------------------------------------------------| | `V` | the*witness value* , which will be the same as the expected value if successful
| ### compareAndSet Added in[API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public final boolean compareAndSet (V expectedValue, V newValue) ``` Atomically sets the value to`newValue`if the current value`== expectedValue`, with memory effects as specified by[VarHandle.compareAndSet](https://developer.android.com/reference/java/lang/invoke/VarHandle#compareAndSet(java.lang.Object[])).
| Parameters || |-----------------|--------------------------------| | `expectedValue` | `V`: the expected value
| | `newValue` | `V`: the new value
| | Returns || |-----------|---------------------------------------------------------------------------------------------------------------| | `boolean` | `true`if successful. False return indicates that the actual value was not equal to the expected value.
| ### get Added in[API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public final V get () ``` Returns the current value, with memory effects as specified by[VarHandle.getVolatile](https://developer.android.com/reference/java/lang/invoke/VarHandle#getVolatile(java.lang.Object[])).
| Returns || |-----|--------------------------| | `V` | the current value
| ### getAcquire Added in[API level 33](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public final V getAcquire () ``` Returns the current value, with memory effects as specified by[VarHandle.getAcquire](https://developer.android.com/reference/java/lang/invoke/VarHandle#getAcquire(java.lang.Object[])).
| Returns || |-----|------------------| | `V` | the value
| ### getAndAccumulate Added in[API level 24](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public final V getAndAccumulate (V x, BinaryOperator accumulatorFunction) ``` Atomically updates (with memory effects as specified by[VarHandle.compareAndSet(Object)](https://developer.android.com/reference/java/lang/invoke/VarHandle#compareAndSet(java.lang.Object[]))) the current value with the results of applying the given function to the current and given values, returning the previous value. The function should be side-effect-free, since it may be re-applied when attempted updates fail due to contention among threads. The function is applied with the current value as its first argument, and the given update as the second argument.
| Parameters || |-----------------------|-----------------------------------------------------------------------| | `x` | `V`: the update value
| | `accumulatorFunction` | `BinaryOperator`: a side-effect-free function of two arguments
| | Returns || |-----|---------------------------| | `V` | the previous value
| ### getAndSet Added in[API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public final V getAndSet (V newValue) ``` Atomically sets the value to`newValue`and returns the old value, with memory effects as specified by[VarHandle.getAndSet](https://developer.android.com/reference/java/lang/invoke/VarHandle#getAndSet(java.lang.Object[])).
| Parameters || |------------|---------------------------| | `newValue` | `V`: the new value
| | Returns || |-----|---------------------------| | `V` | the previous value
| ### getAndUpdate Added in[API level 24](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public final V getAndUpdate (UnaryOperator updateFunction) ``` Atomically updates (with memory effects as specified by[VarHandle.compareAndSet(Object)](https://developer.android.com/reference/java/lang/invoke/VarHandle#compareAndSet(java.lang.Object[]))) the current value with the results of applying the given function, returning the previous value. The function should be side-effect-free, since it may be re-applied when attempted updates fail due to contention among threads.
| Parameters || |------------------|-----------------------------------------------------| | `updateFunction` | `UnaryOperator`: a side-effect-free function
| | Returns || |-----|---------------------------| | `V` | the previous value
| ### getOpaque Added in[API level 33](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public final V getOpaque () ``` Returns the current value, with memory effects as specified by[VarHandle.getOpaque](https://developer.android.com/reference/java/lang/invoke/VarHandle#getOpaque(java.lang.Object[])).
| Returns || |-----|------------------| | `V` | the value
| ### getPlain Added in[API level 33](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public final V getPlain () ``` Returns the current value, with memory semantics of reading as if the variable was declared non-`volatile`.
| Returns || |-----|------------------| | `V` | the value
| ### lazySet Added in[API level 9](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public final void lazySet (V newValue) ``` Sets the value to`newValue`, with memory effects as specified by[VarHandle.setRelease](https://developer.android.com/reference/java/lang/invoke/VarHandle#setRelease(java.lang.Object[])).
| Parameters || |------------|---------------------------| | `newValue` | `V`: the new value
| ### set Added in[API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public final void set (V newValue) ``` Sets the value to`newValue`, with memory effects as specified by[VarHandle.setVolatile](https://developer.android.com/reference/java/lang/invoke/VarHandle#setVolatile(java.lang.Object[])).
| Parameters || |------------|---------------------------| | `newValue` | `V`: the new value
| ### setOpaque Added in[API level 33](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public final void setOpaque (V newValue) ``` Sets the value to`newValue`, with memory effects as specified by[VarHandle.setOpaque](https://developer.android.com/reference/java/lang/invoke/VarHandle#setOpaque(java.lang.Object[])).
| Parameters || |------------|---------------------------| | `newValue` | `V`: the new value
| ### setPlain Added in[API level 33](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public final void setPlain (V newValue) ``` Sets the value to`newValue`, with memory semantics of setting as if the variable was declared non-`volatile`and non-`final`.
| Parameters || |------------|---------------------------| | `newValue` | `V`: the new value
| ### setRelease Added in[API level 33](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public final void setRelease (V newValue) ``` Sets the value to`newValue`, with memory effects as specified by[VarHandle.setRelease](https://developer.android.com/reference/java/lang/invoke/VarHandle#setRelease(java.lang.Object[])).
| Parameters || |------------|---------------------------| | `newValue` | `V`: the new value
| ### toString Added in[API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public String toString () ``` Returns the String representation of the current value.
| Returns || |--------------------------------------------------------------------|-------------------------------------------------------| | [String](https://developer.android.com/reference/java/lang/String) | the String representation of the current value
| ### updateAndGet Added in[API level 24](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public final V updateAndGet (UnaryOperator updateFunction) ``` Atomically updates (with memory effects as specified by[VarHandle.compareAndSet(Object)](https://developer.android.com/reference/java/lang/invoke/VarHandle#compareAndSet(java.lang.Object[]))) the current value with the results of applying the given function, returning the updated value. The function should be side-effect-free, since it may be re-applied when attempted updates fail due to contention among threads.
| Parameters || |------------------|-----------------------------------------------------| | `updateFunction` | `UnaryOperator`: a side-effect-free function
| | Returns || |-----|--------------------------| | `V` | the updated value
| ### weakCompareAndSet Added in[API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) Deprecated in[API level 33](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public final boolean weakCompareAndSet (V expectedValue, V newValue) ```
**This method was deprecated in API level 33.** This method has plain memory effects but the method name implies volatile memory effects (see methods such as[compareAndExchange(V, V)](https://developer.android.com/reference/java/util/concurrent/atomic/AtomicReference#compareAndExchange(V,%20V))and[compareAndSet(V, V)](https://developer.android.com/reference/java/util/concurrent/atomic/AtomicReference#compareAndSet(V,%20V))). To avoid confusion over plain or volatile memory effects it is recommended that the method[weakCompareAndSetPlain(V, V)](https://developer.android.com/reference/java/util/concurrent/atomic/AtomicReference#weakCompareAndSetPlain(V,%20V))be used instead. Possibly atomically sets the value to`newValue`if the current value`== expectedValue`, with memory effects as specified by[VarHandle.weakCompareAndSetPlain](https://developer.android.com/reference/java/lang/invoke/VarHandle#weakCompareAndSetPlain(java.lang.Object[])).
| Parameters || |-----------------|--------------------------------| | `expectedValue` | `V`: the expected value
| | `newValue` | `V`: the new value
| | Returns || |-----------|----------------------------| | `boolean` | `true`if successful
| **See also:** - [weakCompareAndSetPlain(V, V)](https://developer.android.com/reference/java/util/concurrent/atomic/AtomicReference#weakCompareAndSetPlain(V,%20V)) ### weakCompareAndSetAcquire Added in[API level 33](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public final boolean weakCompareAndSetAcquire (V expectedValue, V newValue) ``` Possibly atomically sets the value to`newValue`if the current value`== expectedValue`, with memory effects as specified by[VarHandle.weakCompareAndSetAcquire](https://developer.android.com/reference/java/lang/invoke/VarHandle#weakCompareAndSetAcquire(java.lang.Object[])).
| Parameters || |-----------------|--------------------------------| | `expectedValue` | `V`: the expected value
| | `newValue` | `V`: the new value
| | Returns || |-----------|----------------------------| | `boolean` | `true`if successful
| ### weakCompareAndSetPlain Added in[API level 33](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public final boolean weakCompareAndSetPlain (V expectedValue, V newValue) ``` Possibly atomically sets the value to`newValue`if the current value`== expectedValue`, with memory effects as specified by[VarHandle.weakCompareAndSetPlain](https://developer.android.com/reference/java/lang/invoke/VarHandle#weakCompareAndSetPlain(java.lang.Object[])).
| Parameters || |-----------------|--------------------------------| | `expectedValue` | `V`: the expected value
| | `newValue` | `V`: the new value
| | Returns || |-----------|----------------------------| | `boolean` | `true`if successful
| ### weakCompareAndSetRelease Added in[API level 33](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public final boolean weakCompareAndSetRelease (V expectedValue, V newValue) ``` Possibly atomically sets the value to`newValue`if the current value`== expectedValue`, with memory effects as specified by[VarHandle.weakCompareAndSetRelease](https://developer.android.com/reference/java/lang/invoke/VarHandle#weakCompareAndSetRelease(java.lang.Object[])).
| Parameters || |-----------------|--------------------------------| | `expectedValue` | `V`: the expected value
| | `newValue` | `V`: the new value
| | Returns || |-----------|----------------------------| | `boolean` | `true`if successful
| ### weakCompareAndSetVolatile Added in[API level 33](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public final boolean weakCompareAndSetVolatile (V expectedValue, V newValue) ``` Possibly atomically sets the value to`newValue`if the current value`== expectedValue`, with memory effects as specified by[VarHandle.weakCompareAndSet](https://developer.android.com/reference/java/lang/invoke/VarHandle#weakCompareAndSet(java.lang.Object[])).
| Parameters || |-----------------|--------------------------------| | `expectedValue` | `V`: the expected value
| | `newValue` | `V`: the new value
| | Returns || |-----------|----------------------------| | `boolean` | `true`if successful
|