jsat.utils.concurrent

Class AtomicDoubleArray

java.lang.Object

jsat.utils.concurrent.AtomicDoubleArray

All Implemented Interfaces:

java.io.Serializable

public class AtomicDoubleArray
extends java.lang.Object
implements java.io.Serializable

Provides a double array that can have individual values updated atomically. It is backed by and mimics the implementation of AtomicLongArray. As such, the methods have the same documentation

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
AtomicDoubleArray(double[] array) Creates a new AtomixDouble Array that is of the same length as the input array.
AtomicDoubleArray(int length) Creates a new AtomicDoubleArray of the given length, with all values initialized to zero

Method Summary

Modifier and Type	Method and Description
double	accumulateAndGet(int i, double x, java.util.function.DoubleBinaryOperator 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.
double	addAndGet(int i, double delta) Atomically adds the given value to the element at index i.
boolean	compareAndSet(int i, double expected, double update) Atomically sets the element at position i to the given updated value if the current value == the expected value.
void	fill(double value) This is a convenience method to set every value in this array to a specified value
double	get(int i) Gets the current value at position i.
double	getAndAccumulate(int i, double x, java.util.function.DoubleBinaryOperator 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.
double	getAndAdd(int i, double delta) Atomically adds the given value to the element at index i.
double	getAndDecrement(int i) Atomically decrements by one the element at index i.
double	getAndIncrement(int i) Atomically increments by one the element at index i.
double	getAndSet(int i, double newValue) Atomically sets the element at position i to the given value and returns the old value.
double	getAndUpdate(int i, java.util.function.DoubleUnaryOperator updateFunction) Atomically updates the element at index i with the results of applying the given function, returning the previous value.
void	lazySet(int i, double newValue) Eventually sets the element at position i to the given value.
int	length() Returns the length of the array.
void	set(int i, double newValue) Sets the element at position i to the given value.
double	updateAndGet(int i, java.util.function.DoubleUnaryOperator updateFunction) Atomically updates the element at index i with the results of applying the given function, returning the updated value.
boolean	weakCompareAndSet(int i, double expected, double 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

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

AtomicDoubleArray

public AtomicDoubleArray(int length)

Creates a new AtomicDoubleArray of the given length, with all values initialized to zero

Parameters:

length - the length of the array

AtomicDoubleArray

public AtomicDoubleArray(double[] array)

Creates a new AtomixDouble Array that is of the same length as the input array. The values will be copied into the new object

Parameters:

array - the array of values to copy

Method Detail

getAndIncrement

public double getAndIncrement(int i)

Atomically increments by one the element at index i.

Parameters:

i - the index

Returns:

the previous value

getAndDecrement

public double getAndDecrement(int i)

Atomically decrements by one the element at index i.

Parameters:

i - the index

Returns:

the previous value

getAndAdd

public double getAndAdd(int i,
                        double 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

addAndGet

public double addAndGet(int i,
                        double 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

getAndSet

public double getAndSet(int i,
                        double 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

set

public void set(int i,
                double newValue)

Sets the element at position i to the given value.

Parameters:

i - the index

newValue - the new value

lazySet

public void lazySet(int i,
                    double newValue)

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

Parameters:

i - the index

newValue - the new value

compareAndSet

public boolean compareAndSet(int i,
                             double expected,
                             double update)

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

Parameters:

i - the index

expected - 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 boolean weakCompareAndSet(int i,
                                 double expected,
                                 double 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

expected - the expected value

update - the new value

Returns:

true if successful.

updateAndGet

public final double updateAndGet(int i,
                                 java.util.function.DoubleUnaryOperator 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

getAndUpdate

public final double getAndUpdate(int i,
                                 java.util.function.DoubleUnaryOperator 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

getAndAccumulate

public final double getAndAccumulate(int i,
                                     double x,
                                     java.util.function.DoubleBinaryOperator 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

accumulateAndGet

public final double accumulateAndGet(int i,
                                     double x,
                                     java.util.function.DoubleBinaryOperator 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

get

public double get(int i)

Gets the current value at position i.

Parameters:

i - the index

Returns:

the current value

length

public int length()

Returns the length of the array.

Returns:

the length of the array

fill

public void fill(double value)

This is a convenience method to set every value in this array to a specified value

Parameters:

value - the value fill with