AtomicLongArray

public class AtomicLongArray extends Object
implements Serializable

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

Public Constructor Summary

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 Method Summary

final long
accumulateAndGet(int i, long x, LongBinaryOperator 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.
long
addAndGet(int i, long delta)
Atomically adds the given value to the element at index i.
final boolean
compareAndSet(int i, long expect, long update)
Atomically sets the element at position i to the given updated value if the current value == the expected value.
final long
decrementAndGet(int i)
Atomically decrements by one the element at index i.
final long
get(int i)
Gets the current value at position i.
final long
getAndAccumulate(int i, long x, LongBinaryOperator 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.
final long
getAndAdd(int i, long delta)
Atomically adds the given value to the element at index i.
final long
getAndDecrement(int i)
Atomically decrements by one the element at index i.
final long
getAndIncrement(int i)
Atomically increments by one the element at index i.
final long
getAndSet(int i, long newValue)
Atomically sets the element at position i to the given value and returns the old value.
final long
getAndUpdate(int i, LongUnaryOperator updateFunction)
Atomically updates the element at index i with the results of applying the given function, returning the previous value.
final long
incrementAndGet(int i)
Atomically increments by one the element at index i.
final void
lazySet(int i, long newValue)
Eventually sets the element at position i to the given value.
final int
length()
Returns the length of the array.
final void
set(int i, long newValue)
Sets the element at position i to the given value.
String
toString()
Returns the String representation of the current values of array.
final long
updateAndGet(int i, LongUnaryOperator updateFunction)
Atomically updates the element at index i with the results of applying the given function, returning the updated value.
final boolean
weakCompareAndSet(int i, long expect, long update)
Atomically sets the element at position i to the given updated value if the current value == the expected value.

Inherited Method Summary

Public Constructors

public AtomicLongArray (int length)

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

Parameters
length the length of the array

public AtomicLongArray (long[] array)

Creates a new AtomicLongArray 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

Public Methods

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

public long addAndGet (int i, long delta)

Atomically adds the given value to the element at index i.

Parameters
i the index
delta the value to add
Returns
  • the updated value

public final boolean compareAndSet (int i, long expect, long 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.

public final long decrementAndGet (int i)

Atomically decrements by one the element at index i.

Parameters
i the index
Returns
  • the updated value

public final long get (int i)

Gets the current value at position i.

Parameters
i the index
Returns
  • the current value

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

public final long getAndAdd (int i, long delta)

Atomically adds the given value to the element at index i.

Parameters
i the index
delta the value to add
Returns
  • the previous value

public final long getAndDecrement (int i)

Atomically decrements by one the element at index i.

Parameters
i the index
Returns
  • the previous value

public final long getAndIncrement (int i)

Atomically increments by one the element at index i.

Parameters
i the index
Returns
  • the previous value

public final long getAndSet (int i, long 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

public final long getAndUpdate (int i, LongUnaryOperator 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

public final long incrementAndGet (int i)

Atomically increments by one the element at index i.

Parameters
i the index
Returns
  • the updated value

public final void lazySet (int i, long newValue)

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

Parameters
i the index
newValue the new value

public final int length ()

Returns the length of the array.

Returns
  • the length of the array

public final void set (int i, long newValue)

Sets the element at position i to the given value.

Parameters
i the index
newValue the new value

public String toString ()

Returns the String representation of the current values of array.

Returns
  • the String representation of the current values of array

public final long updateAndGet (int i, LongUnaryOperator 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

public final boolean weakCompareAndSet (int i, long expect, long 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