Class AtomicReferenceArray<E>

Type Parameters:
E - The base class of elements held in this array
All Implemented Interfaces:
Serializable

public class AtomicReferenceArray<E>
extends Object
implements Serializable

An array of object references in which elements may be updated atomically. See the java.util.concurrent.atomic package specification for description of the properties of atomic variables.

Since:
1.5
See Also:
Serialized Form

Constructors

Constructor and Description
AtomicReferenceArray(E[] array)

Creates a new AtomicReferenceArray with the same length as, and all elements copied from, the given array.
AtomicReferenceArray(int length)

Creates a new AtomicReferenceArray of the given length, with all elements initially null.

Methods

Modifier and Type Method and Description
E accumulateAndGet(int i, E x, BinaryOperator<E> accumulatorFunction)

Atomically updates the element at index i with the results of applying the given function to the current and given values, returning the updated value.
boolean compareAndSet(int i, E expect, E update)

Atomically sets the element at position i to the given updated value if the current value == the expected value.
E get(int i)

Gets the current value at position i.
E getAndAccumulate(int i, E x, BinaryOperator<E> accumulatorFunction)

Atomically updates the element at index i with the results of applying the given function to the current and given values, returning the previous value.
E getAndSet(int i, E newValue)

Atomically sets the element at position i to the given value and returns the old value.
E getAndUpdate(int i, UnaryOperator<E> updateFunction)

Atomically updates the element at index i with the results of applying the given function, returning the previous value.
void lazySet(int i, E newValue)

Eventually sets the element at position i to the given value.
int length()

Returns the length of the array.
void set(int i, E newValue)

Sets the element at position i to the given value.
String toString()

Returns the String representation of the current values of array.
E updateAndGet(int i, UnaryOperator<E> updateFunction)

Atomically updates the element at index i with the results of applying the given function, returning the updated value.
boolean weakCompareAndSet(int i, E expect, E update)

Atomically sets the element at position i to the given updated value if the current value == the expected value.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructors

AtomicReferenceArray

public AtomicReferenceArray(int length)

Creates a new AtomicReferenceArray of the given length, with all elements initially null.

Parameters:
length - the length of the array

AtomicReferenceArray

public AtomicReferenceArray(E[] array)

Creates a new AtomicReferenceArray with the same length as, and all elements copied from, the given array.

Parameters:
array - the array to copy elements from
Throws:
NullPointerException - if array is null

Methods

length

public final int length()

Returns the length of the array.

Returns:
the length of the array

get

public final E get(int i)

Gets the current value at position i.

Parameters:
i - the index
Returns:
the current value

set

public final void set(int i,
                      E newValue)

Sets the element at position i to the given value.

Parameters:
i - the index
newValue - the new value

lazySet

public final void lazySet(int i,
                          E newValue)

Eventually sets the element at position i to the given value.

Parameters:
i - the index
newValue - the new value
Since:
1.6

getAndSet

public final E getAndSet(int i,
                         E newValue)

Atomically sets the element at position i to the given value and returns the old value.

Parameters:
i - the index
newValue - the new value
Returns:
the previous value

compareAndSet

public final boolean compareAndSet(int i,
                                   E expect,
                                   E update)

Atomically sets the element at position i to the given updated value if the current value == the expected value.

Parameters:
i - the index
expect - the expected value
update - the new value
Returns:
true if successful. False return indicates that the actual value was not equal to the expected value.

weakCompareAndSet

public final boolean weakCompareAndSet(int i,
                                       E expect,
                                       E update)

Atomically sets the element at position i to the given updated value if the current value == the expected value.

May fail spuriously and does not provide ordering guarantees, so is only rarely an appropriate alternative to compareAndSet.

Parameters:
i - the index
expect - the expected value
update - the new value
Returns:
true if successful

getAndUpdate

public final E getAndUpdate(int i,
                            UnaryOperator<E> updateFunction)

Atomically updates the element at index i 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:
i - the index
updateFunction - a side-effect-free function
Returns:
the previous value
Since:
1.8

updateAndGet

public final E updateAndGet(int i,
                            UnaryOperator<E> updateFunction)

Atomically updates the element at index i 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:
i - the index
updateFunction - a side-effect-free function
Returns:
the updated value
Since:
1.8

getAndAccumulate

public final E getAndAccumulate(int i,
                                E x,
                                BinaryOperator<E> accumulatorFunction)

Atomically updates the element at index i 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 at index i as its first argument, and the given update as the second argument.

Parameters:
i - the index
x - the update value
accumulatorFunction - a side-effect-free function of two arguments
Returns:
the previous value
Since:
1.8

accumulateAndGet

public final E accumulateAndGet(int i,
                                E x,
                                BinaryOperator<E> accumulatorFunction)

Atomically updates the element at index i 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 at index i as its first argument, and the given update as the second argument.

Parameters:
i - the index
x - the update value
accumulatorFunction - a side-effect-free function of two arguments
Returns:
the updated value
Since:
1.8

toString

public String toString()

Returns the String representation of the current values of array.

Overrides:
toString in class Object
Returns:
the String representation of the current values of array

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Documentation extracted from Debian's OpenJDK Development Kit package.
Licensed under the GNU General Public License, version 2, with the Classpath Exception.
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https://docs.oracle.com/javase/8/docs/api/java/util/concurrent/atomic/AtomicReferenceArray.html