Class AtomicIntegerArray

Constructors

AtomicIntegerArray

public AtomicIntegerArray(int length)

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

Parameters:

length - the length of the array

AtomicIntegerArray

public AtomicIntegerArray(int[] array)

Creates a new AtomicIntegerArray 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 int get(int i)

Returns the current value of the element at index i, with memory effects as specified by VarHandle.getVolatile(java.lang.Object...).

Parameters:

i - the index

Returns:

the current value

set

public final void set(int i,
                      int newValue)

Sets the element at index i to newValue, with memory effects as specified by VarHandle.setVolatile(java.lang.Object...).

Parameters:

i - the index

newValue - the new value

lazySet

public final void lazySet(int i,
                          int newValue)

Sets the element at index i to newValue, with memory effects as specified by VarHandle.setRelease(java.lang.Object...).

Parameters:

i - the index

newValue - the new value

Since:

1.6

getAndSet

public final int getAndSet(int i,
                           int newValue)

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

Parameters:

i - the index

newValue - the new value

Returns:

the previous value

compareAndSet

public final boolean compareAndSet(int i,
                                   int expectedValue,
                                   int 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(java.lang.Object...).

Parameters:

i - the index

expectedValue - the expected value

newValue - the new value

Returns:

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

weakCompareAndSet

@Deprecated(since="9")
public final boolean weakCompareAndSet(int i,
                                       int expectedValue,
                                       int 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(java.lang.Object...).

Parameters:

i - the index

expectedValue - the expected value

newValue - the new value

Returns:

true if successful

See Also:

weakCompareAndSetPlain(int, int, int)

weakCompareAndSetPlain

public final boolean weakCompareAndSetPlain(int i,
                                            int expectedValue,
                                            int 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(java.lang.Object...).

Parameters:

i - the index

expectedValue - the expected value

newValue - the new value

Returns:

true if successful

Since:

9

getAndIncrement

public final int getAndIncrement(int i)

Parameters:

i - the index

Returns:

the previous value

getAndDecrement

public final int getAndDecrement(int i)

Parameters:

i - the index

Returns:

the previous value

getAndAdd

public final int getAndAdd(int i,
                           int delta)

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

Parameters:

i - the index

delta - the value to add

Returns:

the previous value

incrementAndGet

public final int incrementAndGet(int i)

Parameters:

i - the index

Returns:

the updated value

decrementAndGet

public final int decrementAndGet(int i)

Parameters:

i - the index

Returns:

the updated value

addAndGet

public final int addAndGet(int i,
                           int delta)

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

Parameters:

i - the index

delta - the value to add

Returns:

the updated value

getAndUpdate

public final int getAndUpdate(int i,
                              IntUnaryOperator updateFunction)

Atomically updates (with memory effects as specified by VarHandle.compareAndSet(java.lang.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 - the index

updateFunction - a side-effect-free function

Returns:

the previous value

Since:

1.8

updateAndGet

public final int updateAndGet(int i,
                              IntUnaryOperator updateFunction)

Atomically updates (with memory effects as specified by VarHandle.compareAndSet(java.lang.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 - the index

updateFunction - a side-effect-free function

Returns:

the updated value

Since:

1.8

getAndAccumulate

public final int getAndAccumulate(int i,
                                  int x,
                                  IntBinaryOperator accumulatorFunction)

Atomically updates (with memory effects as specified by VarHandle.compareAndSet(java.lang.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 - 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 int accumulateAndGet(int i,
                                  int x,
                                  IntBinaryOperator accumulatorFunction)

Atomically updates (with memory effects as specified by VarHandle.compareAndSet(java.lang.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 - 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

getPlain

public final int 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 - the index

Returns:

the value

Since:

9

setPlain

public final void setPlain(int i,
                           int 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 - the index

newValue - the new value

Since:

9

getOpaque

public final int getOpaque(int i)

Returns the current value of the element at index i, with memory effects as specified by VarHandle.getOpaque(java.lang.Object...).

Parameters:

i - the index

Returns:

the value

Since:

9

setOpaque

public final void setOpaque(int i,
                            int newValue)

Sets the element at index i to newValue, with memory effects as specified by VarHandle.setOpaque(java.lang.Object...).

Parameters:

i - the index

newValue - the new value

Since:

9

getAcquire

public final int getAcquire(int i)

Returns the current value of the element at index i, with memory effects as specified by VarHandle.getAcquire(java.lang.Object...).

Parameters:

i - the index

Returns:

the value

Since:

9

setRelease

public final void setRelease(int i,
                             int newValue)

Sets the element at index i to newValue, with memory effects as specified by VarHandle.setRelease(java.lang.Object...).

Parameters:

i - the index

newValue - the new value

Since:

9

compareAndExchange

public final int compareAndExchange(int i,
                                    int expectedValue,
                                    int 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(java.lang.Object...).

Parameters:

i - the index

expectedValue - the expected value

newValue - the new value

Returns:

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

Since:

9

compareAndExchangeAcquire

public final int compareAndExchangeAcquire(int i,
                                           int expectedValue,
                                           int 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(java.lang.Object...).

Parameters:

i - the index

expectedValue - the expected value

newValue - the new value

Returns:

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

Since:

9

compareAndExchangeRelease

public final int compareAndExchangeRelease(int i,
                                           int expectedValue,
                                           int 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(java.lang.Object...).

Parameters:

i - the index

expectedValue - the expected value

newValue - the new value

Returns:

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

Since:

9

weakCompareAndSetVolatile

public final boolean weakCompareAndSetVolatile(int i,
                                               int expectedValue,
                                               int 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(java.lang.Object...).

Parameters:

i - the index

expectedValue - the expected value

newValue - the new value

Returns:

true if successful

Since:

9

weakCompareAndSetAcquire

public final boolean weakCompareAndSetAcquire(int i,
                                              int expectedValue,
                                              int 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(java.lang.Object...).

Parameters:

i - the index

expectedValue - the expected value

newValue - the new value

Returns:

true if successful

Since:

9

weakCompareAndSetRelease

public final boolean weakCompareAndSetRelease(int i,
                                              int expectedValue,
                                              int 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(java.lang.Object...).

Parameters:

i - the index

expectedValue - the expected value

newValue - the new value

Returns:

true if successful

Since:

9