Added in API level 1

Summary: Ctors | Methods | Inherited Methods

AtomicLongArray

public class AtomicLongArray
extends Object implements Serializable

java.lang.Object
↳	java.util.concurrent.atomic.AtomicLongArray

---

A long array in which elements may be updated atomically. See the VarHandle specification for descriptions of the properties of atomic accesses.

Summary

Public constructors
AtomicLongArray(int length) Creates a new AtomicLongArray of the given length, with all elements initially zero.
AtomicLongArray(long[] array) Creates a new AtomicLongArray with the same length as, and all elements copied from, the given array.

Public methods
final long	accumulateAndGet(int i, long x, LongBinaryOperator accumulatorFunction) Atomically updates (with memory effects as specified by VarHandle.compareAndSet(Object)) the element at index i with the results of applying the given function to the current and given values, returning the updated value.
long	addAndGet(int i, long delta) Atomically adds the given value to the element at index i, with memory effects as specified by VarHandle.getAndAdd.
final long	compareAndExchange(int i, long expectedValue, long newValue) Atomically sets the element at index i to newValue if the element's current value, referred to as the witness value, == expectedValue, with memory effects as specified by VarHandle.compareAndExchange.
final long	compareAndExchangeAcquire(int i, long expectedValue, long newValue) Atomically sets the element at index i to newValue if the element's current value, referred to as the witness value, == expectedValue, with memory effects as specified by VarHandle.compareAndExchangeAcquire.
final long	compareAndExchangeRelease(int i, long expectedValue, long newValue) Atomically sets the element at index i to newValue if the element's current value, referred to as the witness value, == expectedValue, with memory effects as specified by VarHandle.compareAndExchangeRelease.
final boolean	compareAndSet(int i, long expectedValue, long newValue) Atomically sets the element at index i to newValue if the element's current value == expectedValue, with memory effects as specified by VarHandle.compareAndSet.
final long	decrementAndGet(int i) Atomically decrements the value of the element at index i, with memory effects as specified by VarHandle.getAndAdd.
final long	get(int i) Returns the current value of the element at index i, with memory effects as specified by VarHandle.getVolatile.
final long	getAcquire(int i) Returns the current value of the element at index i, with memory effects as specified by VarHandle.getAcquire.
final long	getAndAccumulate(int i, long x, LongBinaryOperator accumulatorFunction) Atomically updates (with memory effects as specified by VarHandle.compareAndSet(Object)) the element at index i with the results of applying the given function to the current and given values, returning the previous value.
final long	getAndAdd(int i, long delta) Atomically adds the given value to the element at index i, with memory effects as specified by VarHandle.getAndAdd.
final long	getAndDecrement(int i) Atomically decrements the value of the element at index i, with memory effects as specified by VarHandle.getAndAdd.
final long	getAndIncrement(int i) Atomically increments the value of the element at index i, with memory effects as specified by VarHandle.getAndAdd.
final long	getAndSet(int i, long newValue) Atomically sets the element at index i to newValue and returns the old value, with memory effects as specified by VarHandle.getAndSet.
final long	getAndUpdate(int i, LongUnaryOperator updateFunction) Atomically updates (with memory effects as specified by VarHandle.compareAndSet(Object)) the element at index i with the results of applying the given function, returning the previous value.
final long	getOpaque(int i) Returns the current value of the element at index i, with memory effects as specified by VarHandle.getOpaque.
final long	getPlain(int i) Returns the current value of the element at index i, with memory semantics of reading as if the variable was declared non-volatile.
final long	incrementAndGet(int i) Atomically increments the value of the element at index i, with memory effects as specified by VarHandle.getAndAdd.
final void	lazySet(int i, long newValue) Sets the element at index i to newValue, with memory effects as specified by VarHandle.setRelease.
final int	length() Returns the length of the array.
final void	set(int i, long newValue) Sets the element at index i to newValue, with memory effects as specified by VarHandle.setVolatile.
final void	setOpaque(int i, long newValue) Sets the element at index i to newValue, with memory effects as specified by VarHandle.setOpaque.
final void	setPlain(int i, long newValue) Sets the element at index i to newValue, with memory semantics of setting as if the variable was declared non-volatile and non-final.
final void	setRelease(int i, long newValue) Sets the element at index i to newValue, with memory effects as specified by VarHandle.setRelease.
String	toString() Returns the String representation of the current values of array.
final long	updateAndGet(int i, LongUnaryOperator updateFunction) Atomically updates (with memory effects as specified by VarHandle.compareAndSet(Object)) the element at index i with the results of applying the given function, returning the updated value.
final boolean	weakCompareAndSet(int i, long expectedValue, long 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(int, long, long) and compareAndSet(int, long, long)). To avoid confusion over plain or volatile memory effects it is recommended that the method weakCompareAndSetPlain(int, long, long) be used instead.
final boolean	weakCompareAndSetAcquire(int i, long expectedValue, long newValue) Possibly atomically sets the element at index i to newValue if the element's current value == expectedValue, with memory effects as specified by VarHandle.weakCompareAndSetAcquire.
final boolean	weakCompareAndSetPlain(int i, long expectedValue, long newValue) Possibly atomically sets the element at index i to newValue if the element's current value == expectedValue, with memory effects as specified by VarHandle.weakCompareAndSetPlain.
final boolean	weakCompareAndSetRelease(int i, long expectedValue, long newValue) Possibly atomically sets the element at index i to newValue if the element's current value == expectedValue, with memory effects as specified by VarHandle.weakCompareAndSetRelease.
final boolean	weakCompareAndSetVolatile(int i, long expectedValue, long newValue) Possibly atomically sets the element at index i to newValue if the element's current value == expectedValue, with memory effects as specified by VarHandle.weakCompareAndSet.

Inherited methods

From class java.lang.Object Object clone() Creates and returns a copy of this object. boolean equals(Object obj) Indicates whether some other object is "equal to" this one. void finalize() Called by the garbage collector on an object when garbage collection determines that there are no more references to the object. final Class<?> getClass() Returns the runtime class of this Object. int hashCode() Returns a hash code value for the object. final void notify() Wakes up a single thread that is waiting on this object's monitor. final void notifyAll() Wakes up all threads that are waiting on this object's monitor. String toString() Returns a string representation of the object. final void wait(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(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() Causes the current thread to wait until it is awakened, typically by being notified or interrupted.

Public constructors

AtomicLongArray

Added in API level 1

public AtomicLongArray (int length)

Creates a new AtomicLongArray of the given length, with all elements initially zero.

Parameters
length	int: the length of the array

AtomicLongArray

Added in API level 1

public AtomicLongArray (long[] array)

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

Parameters
array	long: the array to copy elements from

Throws
NullPointerException	if array is null

Public methods

accumulateAndGet

Added in API level 24

public final long accumulateAndGet (int i, 
                long x, 
                LongBinaryOperator accumulatorFunction)

Atomically updates (with memory effects as specified by VarHandle.compareAndSet(Object)) 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 of the element at index i as its first argument, and the given update as the second argument.

Parameters
i	int: the index
x	long: the update value
accumulatorFunction	LongBinaryOperator: a side-effect-free function of two arguments

Returns
long	the updated value

addAndGet

Added in API level 1

public long addAndGet (int i, 
                long delta)

Atomically adds the given value to the element at index i, with memory effects as specified by VarHandle.getAndAdd.

Parameters
i	int: the index
delta	long: the value to add

Returns
long	the updated value

compareAndExchange

Added in API level 33

public final long compareAndExchange (int i, 
                long expectedValue, 
                long newValue)

Atomically sets the element at index i to newValue if the element's current value, referred to as the witness value, == expectedValue, with memory effects as specified by VarHandle.compareAndExchange.

Parameters
i	int: the index
expectedValue	long: the expected value
newValue	long: the new value

Returns
long	the witness value, which will be the same as the expected value if successful

compareAndExchangeAcquire

Added in API level 33

public final long compareAndExchangeAcquire (int i, 
                long expectedValue, 
                long newValue)

Atomically sets the element at index i to newValue if the element's current value, referred to as the witness value, == expectedValue, with memory effects as specified by VarHandle.compareAndExchangeAcquire.

Parameters
i	int: the index
expectedValue	long: the expected value
newValue	long: the new value

Returns
long	the witness value, which will be the same as the expected value if successful

compareAndExchangeRelease

Added in API level 33

public final long compareAndExchangeRelease (int i, 
                long expectedValue, 
                long newValue)

Atomically sets the element at index i to newValue if the element's current value, referred to as the witness value, == expectedValue, with memory effects as specified by VarHandle.compareAndExchangeRelease.

Parameters
i	int: the index
expectedValue	long: the expected value
newValue	long: the new value

Returns
long	the witness value, which will be the same as the expected value if successful

compareAndSet

Added in API level 1

public final boolean compareAndSet (int i, 
                long expectedValue, 
                long newValue)

Atomically sets the element at index i to newValue if the element's current value == expectedValue, with memory effects as specified by VarHandle.compareAndSet.

Parameters
i	int: the index
expectedValue	long: the expected value
newValue	long: the new value

Returns
boolean	true if successful. False return indicates that the actual value was not equal to the expected value.

decrementAndGet

Added in API level 1

public final long decrementAndGet (int i)

Atomically decrements the value of the element at index i, with memory effects as specified by VarHandle.getAndAdd.

Equivalent to addAndGet(i, -1).

Parameters
i	int: the index

Returns
long	the updated value

get

Added in API level 1

public final long get (int i)

Returns the current value of the element at index i, with memory effects as specified by VarHandle.getVolatile.

Parameters
i	int: the index

Returns
long	the current value

getAcquire

Added in API level 33

public final long getAcquire (int i)

Returns the current value of the element at index i, with memory effects as specified by VarHandle.getAcquire.

Parameters
i	int: the index

Returns
long	the value

getAndAccumulate

Added in API level 24

public final long getAndAccumulate (int i, 
                long x, 
                LongBinaryOperator accumulatorFunction)

Atomically updates (with memory effects as specified by VarHandle.compareAndSet(Object)) 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 of the element at index i as its first argument, and the given update as the second argument.

Parameters
i	int: the index
x	long: the update value
accumulatorFunction	LongBinaryOperator: a side-effect-free function of two arguments

Returns
long	the previous value

getAndAdd

Added in API level 1

public final long getAndAdd (int i, 
                long delta)

Atomically adds the given value to the element at index i, with memory effects as specified by VarHandle.getAndAdd.

Parameters
i	int: the index
delta	long: the value to add

Returns
long	the previous value

getAndDecrement

Added in API level 1

public final long getAndDecrement (int i)

Atomically decrements the value of the element at index i, with memory effects as specified by VarHandle.getAndAdd.

Equivalent to getAndAdd(i, -1).

Parameters
i	int: the index

Returns
long	the previous value

getAndIncrement

Added in API level 1

public final long getAndIncrement (int i)

Atomically increments the value of the element at index i, with memory effects as specified by VarHandle.getAndAdd.

Equivalent to getAndAdd(i, 1).

Parameters
i	int: the index

Returns
long	the previous value

getAndSet

Added in API level 1

public final long getAndSet (int i, 
                long newValue)

Atomically sets the element at index i to newValue and returns the old value, with memory effects as specified by VarHandle.getAndSet.

Parameters
i	int: the index
newValue	long: the new value

Returns
long	the previous value

getAndUpdate

Added in API level 24

public final long getAndUpdate (int i, 
                LongUnaryOperator updateFunction)

Atomically updates (with memory effects as specified by VarHandle.compareAndSet(Object)) 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	int: the index
updateFunction	LongUnaryOperator: a side-effect-free function

Returns
long	the previous value

getOpaque

Added in API level 33

public final long getOpaque (int i)

Returns the current value of the element at index i, with memory effects as specified by VarHandle.getOpaque.

Parameters
i	int: the index

Returns
long	the value

getPlain

Added in API level 33

public final long getPlain (int i)

Returns the current value of the element at index i, with memory semantics of reading as if the variable was declared non-volatile.

Parameters
i	int: the index

Returns
long	the value

incrementAndGet

Added in API level 1

public final long incrementAndGet (int i)

Atomically increments the value of the element at index i, with memory effects as specified by VarHandle.getAndAdd.

Equivalent to addAndGet(i, 1).

Parameters
i	int: the index

Returns
long	the updated value

lazySet

Added in API level 9

public final void lazySet (int i, 
                long newValue)

Sets the element at index i to newValue, with memory effects as specified by VarHandle.setRelease.

Parameters
i	int: the index
newValue	long: the new value

length

Added in API level 1

public final int length ()

Returns the length of the array.

Returns
int	the length of the array

set

Added in API level 1

public final void set (int i, 
                long newValue)

Sets the element at index i to newValue, with memory effects as specified by VarHandle.setVolatile.

Parameters
i	int: the index
newValue	long: the new value

setOpaque

Added in API level 33

public final void setOpaque (int i, 
                long newValue)

Sets the element at index i to newValue, with memory effects as specified by VarHandle.setOpaque.

Parameters
i	int: the index
newValue	long: the new value

setPlain

Added in API level 33

public final void setPlain (int i, 
                long newValue)

Sets the element at index i to newValue, with memory semantics of setting as if the variable was declared non-volatile and non-final.

Parameters
i	int: the index
newValue	long: the new value

setRelease

Added in API level 33

public final void setRelease (int i, 
                long newValue)

Sets the element at index i to newValue, with memory effects as specified by VarHandle.setRelease.

Parameters
i	int: the index
newValue	long: the new value

toString

Added in API level 1

public String toString ()

Returns the String representation of the current values of array.

Returns
String	the String representation of the current values of array

updateAndGet

Added in API level 24

public final long updateAndGet (int i, 
                LongUnaryOperator updateFunction)

Atomically updates (with memory effects as specified by VarHandle.compareAndSet(Object)) 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	int: the index
updateFunction	LongUnaryOperator: a side-effect-free function

Returns
long	the updated value

weakCompareAndSet

Added in API level 1
Deprecated in API level 33

public final boolean weakCompareAndSet (int i, 
                long expectedValue, 
                long 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(int, long, long) and compareAndSet(int, long, long)). To avoid confusion over plain or volatile memory effects it is recommended that the method weakCompareAndSetPlain(int, long, long) be used instead.

Possibly atomically sets the element at index i to newValue if the element's current value == expectedValue, with memory effects as specified by VarHandle.weakCompareAndSetPlain.

Parameters
i	int: the index
expectedValue	long: the expected value
newValue	long: the new value

Returns
boolean	true if successful

See also:

• weakCompareAndSetPlain(int, long, long)

weakCompareAndSetAcquire

Added in API level 33

public final boolean weakCompareAndSetAcquire (int i, 
                long expectedValue, 
                long newValue)

Possibly atomically sets the element at index i to newValue if the element's current value == expectedValue, with memory effects as specified by VarHandle.weakCompareAndSetAcquire.

Parameters
i	int: the index
expectedValue	long: the expected value
newValue	long: the new value

Returns
boolean	true if successful

weakCompareAndSetPlain

Added in API level 33

public final boolean weakCompareAndSetPlain (int i, 
                long expectedValue, 
                long newValue)

Possibly atomically sets the element at index i to newValue if the element's current value == expectedValue, with memory effects as specified by VarHandle.weakCompareAndSetPlain.

Parameters
i	int: the index
expectedValue	long: the expected value
newValue	long: the new value

Returns
boolean	true if successful

weakCompareAndSetRelease

Added in API level 33

public final boolean weakCompareAndSetRelease (int i, 
                long expectedValue, 
                long newValue)

Possibly atomically sets the element at index i to newValue if the element's current value == expectedValue, with memory effects as specified by VarHandle.weakCompareAndSetRelease.

Parameters
i	int: the index
expectedValue	long: the expected value
newValue	long: the new value

Returns
boolean	true if successful

weakCompareAndSetVolatile

Added in API level 33

public final boolean weakCompareAndSetVolatile (int i, 
                long expectedValue, 
                long newValue)

Possibly atomically sets the element at index i to newValue if the element's current value == expectedValue, with memory effects as specified by VarHandle.weakCompareAndSet.

Parameters
i	int: the index
expectedValue	long: the expected value
newValue	long: the new value

Returns
boolean	true if successful