IAtomicReference (Hazelcast Root 5.0.3 API)

Type Parameters:

E - the type of object referred to by this reference

All Superinterfaces:

DistributedObject
```
public interface IAtomicReference<E>
extends DistributedObject
```
IAtomicReference is a redundant and highly available distributed alternative to the AtomicReference.
Asynchronous variants have been introduced in version 3.7. Async methods immediately return a CompletionStage from which the operation's result can be obtained either in a blocking manner or by registering a callback to be executed upon completion. For example:
```
 CompletionStage<E> future = atomicRef.getAsync();
 future.whenCompleteAsync((v, throwable) -> {
     if (throwable == null) {
         // do something with the old value returned by put operation
     } else {
         // handle failure
     }
 });
 
```
Actions supplied for dependent completions of default non-async methods and async methods without an explicit Executor argument are performed by the ForkJoinPool.commonPool() (unless it does not support a parallelism level of at least 2, in which case a new Thread is created per task).
IAtomicReference is accessed via CPSubsystem.getAtomicReference(String). It works on top of the Raft consensus algorithm. It offers linearizability during crash failures and network partitions. It is CP with respect to the CAP principle. If a network partition occurs, it remains available on at most one side of the partition.
IAtomicReference impl does not offer exactly-once / effectively-once execution semantics. It goes with at-least-once execution semantics by default and can cause an API call to be committed multiple times in case of CP member failures. It can be tuned to offer at-most-once execution semantics. Please see CPSubsystemConfig.setFailOnIndeterminateOperationState(boolean)
Since:

3.2

See Also:

IAtomicLong

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method and Description
`void`	`alter(IFunction<E,E> function)` Alters the currently stored reference by applying a function on it.
`E`	`alterAndGet(IFunction<E,E> function)` Alters the currently stored reference by applying a function on it and gets the result.
`CompletionStage<E>`	`alterAndGetAsync(IFunction<E,E> function)` Alters the currently stored reference by applying a function on it and gets the result.
`CompletionStage<Void>`	`alterAsync(IFunction<E,E> function)` Alters the currently stored reference by applying a function on it.
`<R> R`	`apply(IFunction<E,R> function)` Applies a function on the value, the actual stored value will not change.
`<R> CompletionStage<R>`	`applyAsync(IFunction<E,R> function)` Applies a function on the value, the actual stored value will not change.
`void`	`clear()` Clears the current stored reference.
`CompletionStage<Void>`	`clearAsync()` Clears the current stored reference.
`boolean`	`compareAndSet(E expect, E update)` Atomically sets the value to the given updated value only if the current value `==` the expected value.
`CompletionStage<Boolean>`	`compareAndSetAsync(E expect, E update)` Atomically sets the value to the given updated value only if the current value `==` the expected value.
`boolean`	`contains(E value)` Checks if the reference contains the value.
`CompletionStage<Boolean>`	`containsAsync(E expected)` Checks if the reference contains the value.
`E`	`get()` Gets the current value.
`E`	`getAndAlter(IFunction<E,E> function)` Alters the currently stored reference by applying a function on it on and gets the old value.
`CompletionStage<E>`	`getAndAlterAsync(IFunction<E,E> function)` Alters the currently stored reference by applying a function on it on and gets the old value.
`E`	`getAndSet(E newValue)` Gets the old value and sets the new value.
`CompletionStage<E>`	`getAndSetAsync(E newValue)` Gets the value and sets the new value.
`CompletionStage<E>`	`getAsync()` Gets the current value.
`boolean`	`isNull()` Checks if the stored reference is `null`.
`CompletionStage<Boolean>`	`isNullAsync()` Checks if the stored reference is `null`.
`void`	`set(E newValue)` Atomically sets the given value.
`CompletionStage<Void>`	`setAsync(E newValue)` Atomically sets the given value.

Methods inherited from interface com.hazelcast.core.DistributedObject
destroy, getDestroyContextForTenant, getName, getPartitionKey, getServiceName

- Method Detail
  - compareAndSet
```
boolean compareAndSet(E expect,
                      E update)
```
    Atomically sets the value to the given updated value only if the current value == the expected value.
    
    Parameters:
    
    expect - the expected value
    
    update - the new value
    
    Returns:
    
    true if successful; or false if the actual value was not equal to the expected value
  - get
```
E get()
```
    Gets the current value.
    
    Returns:
    
    the current value
  - set
```
void set(E newValue)
```
    Atomically sets the given value.
    
    Parameters:
    
    newValue - the new value
  - getAndSet
```
E getAndSet(E newValue)
```
    Gets the old value and sets the new value.
    
    Parameters:
    
    newValue - the new value
    
    Returns:
    
    the old value
  - isNull
```
boolean isNull()
```
    Checks if the stored reference is null.
    
    Returns:
    
    true if null, false otherwise
  - clear
```
void clear()
```
    Clears the current stored reference.
  - contains
```
boolean contains(E value)
```
    Checks if the reference contains the value.
    
    Parameters:
    
    value - the value to check (is allowed to be null)
    
    Returns:
    
    true if the value is found, false otherwise
  - alter
```
void alter(IFunction<E,E> function)
```
    Alters the currently stored reference by applying a function on it.
    
    Parameters:
    
    function - the function that alters the currently stored reference
    
    Throws:
    
    IllegalArgumentException - if function is null
  - alterAndGet
```
E alterAndGet(IFunction<E,E> function)
```
    Alters the currently stored reference by applying a function on it and gets the result.
    
    Parameters:
    
    function - the function that alters the currently stored reference
    
    Returns:
    
    the new value, the result of the applied function
    
    Throws:
    
    IllegalArgumentException - if function is null
  - getAndAlter
```
E getAndAlter(IFunction<E,E> function)
```
    Alters the currently stored reference by applying a function on it on and gets the old value.
    
    Parameters:
    
    function - the function that alters the currently stored reference
    
    Returns:
    
    the old value, the value before the function is applied
    
    Throws:
    
    IllegalArgumentException - if function is null
  - apply
```
<R> R apply(IFunction<E,R> function)
```
    Applies a function on the value, the actual stored value will not change.
    
    Type Parameters:
    
    R - the result type of the function
    
    Parameters:
    
    function - the function applied on the value, the stored value does not change
    
    Returns:
    
    the result of the function application
    
    Throws:
    
    IllegalArgumentException - if function is null
  - compareAndSetAsync
```
CompletionStage<Boolean> compareAndSetAsync(E expect,
                                            E update)
```
    Atomically sets the value to the given updated value only if the current value == the expected value.
    
    Parameters:
    
    expect - the expected value
    
    update - the new value
    
    Returns:
    
    true if successful; or false if the actual value was not equal to the expected value
  - getAsync
```
CompletionStage<E> getAsync()
```
    Gets the current value.
    
    Returns:
    
    the current value
  - setAsync
```
CompletionStage<Void> setAsync(E newValue)
```
    Atomically sets the given value.
    
    Parameters:
    
    newValue - the new value
  - getAndSetAsync
```
CompletionStage<E> getAndSetAsync(E newValue)
```
    Gets the value and sets the new value.
    
    Parameters:
    
    newValue - the new value
    
    Returns:
    
    the old value
  - isNullAsync
```
CompletionStage<Boolean> isNullAsync()
```
    Checks if the stored reference is null.
    
    Returns:
    
    true if null, false otherwise
  - clearAsync
```
CompletionStage<Void> clearAsync()
```
    Clears the current stored reference.
  - containsAsync
```
CompletionStage<Boolean> containsAsync(E expected)
```
    Checks if the reference contains the value.
    
    Parameters:
    
    expected - the value to check (is allowed to be null)
    
    Returns:
    
    true if the value is found, false otherwise
  - alterAsync
```
CompletionStage<Void> alterAsync(IFunction<E,E> function)
```
    Alters the currently stored reference by applying a function on it.
    
    Parameters:
    
    function - the function
    
    Throws:
    
    IllegalArgumentException - if function is null
  - alterAndGetAsync
```
CompletionStage<E> alterAndGetAsync(IFunction<E,E> function)
```
    Alters the currently stored reference by applying a function on it and gets the result.
    
    Parameters:
    
    function - the function
    
    Returns:
    
    the new value
    
    Throws:
    
    IllegalArgumentException - if function is null
  - getAndAlterAsync
```
CompletionStage<E> getAndAlterAsync(IFunction<E,E> function)
```
    Alters the currently stored reference by applying a function on it on and gets the old value.
    
    Parameters:
    
    function - the function
    
    Returns:
    
    the old value
    
    Throws:
    
    IllegalArgumentException - if function is null
  - applyAsync
```
<R> CompletionStage<R> applyAsync(IFunction<E,R> function)
```
    Applies a function on the value, the actual stored value will not change.
    
    Type Parameters:
    
    R - the result type of the function
    
    Parameters:
    
    function - the function
    
    Returns:
    
    the result of the function application
    
    Throws:
    
    IllegalArgumentException - if function is null

Interface IAtomicReference<E>

Method Summary

Methods inherited from interface com.hazelcast.core.DistributedObject

Method Detail

compareAndSet

get

set

getAndSet

isNull

clear

contains

alter

alterAndGet

getAndAlter

apply

compareAndSetAsync

getAsync

setAsync

getAndSetAsync

isNullAsync

clearAsync

containsAsync

alterAsync

alterAndGetAsync

getAndAlterAsync

applyAsync