Added in API level 1

AtomicLongFieldUpdater

abstract class AtomicLongFieldUpdater<T : Any!>
kotlin.Any
   ↳ java.util.concurrent.atomic.AtomicLongFieldUpdater

A reflection-based utility that enables atomic updates to designated volatile long fields of designated classes. This class is designed for use in atomic data structures in which several fields of the same node are independently subject to atomic updates.

Note that the guarantees of the compareAndSet method in this class are weaker than in other atomic classes. Because this class cannot ensure that all uses of the field are appropriate for purposes of atomic access, it can guarantee atomicity only with respect to other invocations of compareAndSet and set on the same updater.

Object arguments for parameters of type T that are not instances of the class passed to newUpdater will result in a ClassCastException being thrown.

Summary

Protected constructors

Protected do-nothing constructor for use by subclasses.
Public methods
Long
accumulateAndGet(obj: T, x: Long, accumulatorFunction: LongBinaryOperator!)

Atomically updates (with memory effects as specified by java.lang.invoke.VarHandle#compareAndSet) the field of the given object managed by this updater with the results of applying the given function to the current and given values, returning the updated value.
open Long
addAndGet(obj: T, delta: Long)

Atomically adds the given value to the current value of the field of the given object managed by this updater.
abstract Boolean
compareAndSet(obj: T, expect: Long, update: Long)

Atomically sets the field of the given object managed by this updater to the given updated value if the current value == the expected value.
open Long

Atomically decrements by one the current value of the field of the given object managed by this updater.
abstract Long
get(obj: T)

Returns the current value held in the field of the given object managed by this updater.
Long
getAndAccumulate(obj: T, x: Long, accumulatorFunction: LongBinaryOperator!)

Atomically updates (with memory effects as specified by java.lang.invoke.VarHandle#compareAndSet) the field of the given object managed by this updater with the results of applying the given function to the current and given values, returning the previous value.
open Long
getAndAdd(obj: T, delta: Long)

Atomically adds the given value to the current value of the field of the given object managed by this updater.
open Long

Atomically decrements by one the current value of the field of the given object managed by this updater.
open Long

Atomically increments by one the current value of the field of the given object managed by this updater.
open Long
getAndSet(obj: T, newValue: Long)

Atomically sets the field of the given object managed by this updater to the given value and returns the old value.
Long
getAndUpdate(obj: T, updateFunction: LongUnaryOperator!)

Atomically updates (with memory effects as specified by java.lang.invoke.VarHandle#compareAndSet) the field of the given object managed by this updater with the results of applying the given function, returning the previous value.
open Long

Atomically increments by one the current value of the field of the given object managed by this updater.
abstract Unit
lazySet(obj: T, newValue: Long)

Eventually sets the field of the given object managed by this updater to the given updated value.
open static AtomicLongFieldUpdater<U>!
newUpdater(tclass: Class<U>!, fieldName: String!)

Creates and returns an updater for objects with the given field.
abstract Unit
set(obj: T, newValue: Long)

Sets the field of the given object managed by this updater to the given updated value.
Long
updateAndGet(obj: T, updateFunction: LongUnaryOperator!)

Atomically updates (with memory effects as specified by java.lang.invoke.VarHandle#compareAndSet) the field of the given object managed by this updater with the results of applying the given function, returning the updated value.
abstract Boolean
weakCompareAndSet(obj: T, expect: Long, update: Long)

Atomically sets the field of the given object managed by this updater to the given updated value if the current value == the expected value.

Protected constructors

AtomicLongFieldUpdater

Added in API level 1
protected AtomicLongFieldUpdater()

Protected do-nothing constructor for use by subclasses.

Public methods

accumulateAndGet

Added in API level 24
fun accumulateAndGet(
    obj: T, 
    x: Long, 
    accumulatorFunction: LongBinaryOperator!
): Long

Atomically updates (with memory effects as specified by java.lang.invoke.VarHandle#compareAndSet) the field of the given object managed by this updater 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 as its first argument, and the given update as the second argument.

Parameters
obj T: An object whose field to get and set
x Long: the update value
accumulatorFunction LongBinaryOperator!: a side-effect-free function of two arguments
Return
Long the updated value

addAndGet

Added in API level 1
open fun addAndGet(
    obj: T, 
    delta: Long
): Long

Atomically adds the given value to the current value of the field of the given object managed by this updater.

Parameters
obj T: An object whose field to get and set
delta Long: the value to add
Return
Long the updated value

compareAndSet

Added in API level 1
abstract fun compareAndSet(
    obj: T, 
    expect: Long, 
    update: Long
): Boolean

Atomically sets the field of the given object managed by this updater to the given updated value if the current value == the expected value. This method is guaranteed to be atomic with respect to other calls to compareAndSet and set, but not necessarily with respect to other changes in the field.

Parameters
obj T: An object whose field to conditionally set
expect Long: the expected value
update Long: the new value
Return
Boolean true if successful

decrementAndGet

Added in API level 1
open fun decrementAndGet(obj: T): Long

Atomically decrements by one the current value of the field of the given object managed by this updater.

Parameters
obj T: An object whose field to get and set
Return
Long the updated value

get

Added in API level 1
abstract fun get(obj: T): Long

Returns the current value held in the field of the given object managed by this updater.

Parameters
obj T: An object whose field to get
Return
Long the current value

getAndAccumulate

Added in API level 24
fun getAndAccumulate(
    obj: T, 
    x: Long, 
    accumulatorFunction: LongBinaryOperator!
): Long

Atomically updates (with memory effects as specified by java.lang.invoke.VarHandle#compareAndSet) the field of the given object managed by this updater 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 as its first argument, and the given update as the second argument.

Parameters
obj T: An object whose field to get and set
x Long: the update value
accumulatorFunction LongBinaryOperator!: a side-effect-free function of two arguments
Return
Long the previous value

getAndAdd

Added in API level 1
open fun getAndAdd(
    obj: T, 
    delta: Long
): Long

Atomically adds the given value to the current value of the field of the given object managed by this updater.

Parameters
obj T: An object whose field to get and set
delta Long: the value to add
Return
Long the previous value

getAndDecrement

Added in API level 1
open fun getAndDecrement(obj: T): Long

Atomically decrements by one the current value of the field of the given object managed by this updater.

Parameters
obj T: An object whose field to get and set
Return
Long the previous value

getAndIncrement

Added in API level 1
open fun getAndIncrement(obj: T): Long

Atomically increments by one the current value of the field of the given object managed by this updater.

Parameters
obj T: An object whose field to get and set
Return
Long the previous value

getAndSet

Added in API level 1
open fun getAndSet(
    obj: T, 
    newValue: Long
): Long

Atomically sets the field of the given object managed by this updater to the given value and returns the old value.

Parameters
obj T: An object whose field to get and set
newValue Long: the new value
Return
Long the previous value

getAndUpdate

Added in API level 24
fun getAndUpdate(
    obj: T, 
    updateFunction: LongUnaryOperator!
): Long

Atomically updates (with memory effects as specified by java.lang.invoke.VarHandle#compareAndSet) the field of the given object managed by this updater 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
obj T: An object whose field to get and set
updateFunction LongUnaryOperator!: a side-effect-free function
Return
Long the previous value

incrementAndGet

Added in API level 1
open fun incrementAndGet(obj: T): Long

Atomically increments by one the current value of the field of the given object managed by this updater.

Parameters
obj T: An object whose field to get and set
Return
Long the updated value

lazySet

Added in API level 9
abstract fun lazySet(
    obj: T, 
    newValue: Long
): Unit

Eventually sets the field of the given object managed by this updater to the given updated value.

Parameters
obj T: An object whose field to set
newValue Long: the new value

newUpdater

Added in API level 1
open static fun <U : Any!> newUpdater(
    tclass: Class<U>!, 
    fieldName: String!
): AtomicLongFieldUpdater<U>!

Creates and returns an updater for objects with the given field. The Class argument is needed to check that reflective types and generic types match.

Parameters
tclass Class<U>!: the class of the objects holding the field
fieldName String!: the name of the field to be updated
<U> the type of instances of tclass
Return
AtomicLongFieldUpdater<U>! the updater
Exceptions
java.lang.IllegalArgumentException if the field is not a volatile long type
java.lang.RuntimeException with a nested reflection-based exception if the class does not hold field or is the wrong type, or the field is inaccessible to the caller according to Java language access control

set

Added in API level 1
abstract fun set(
    obj: T, 
    newValue: Long
): Unit

Sets the field of the given object managed by this updater to the given updated value. This operation is guaranteed to act as a volatile store with respect to subsequent invocations of compareAndSet.

Parameters
obj T: An object whose field to set
newValue Long: the new value

updateAndGet

Added in API level 24
fun updateAndGet(
    obj: T, 
    updateFunction: LongUnaryOperator!
): Long

Atomically updates (with memory effects as specified by java.lang.invoke.VarHandle#compareAndSet) the field of the given object managed by this updater 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
obj T: An object whose field to get and set
updateFunction LongUnaryOperator!: a side-effect-free function
Return
Long the updated value

weakCompareAndSet

Added in API level 1
abstract fun weakCompareAndSet(
    obj: T, 
    expect: Long, 
    update: Long
): Boolean

Atomically sets the field of the given object managed by this updater to the given updated value if the current value == the expected value. This method is guaranteed to be atomic with respect to other calls to compareAndSet and set, but not necessarily with respect to other changes in the field.

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

Parameters
obj T: An object whose field to conditionally set
expect Long: the expected value
update Long: the new value
Return
Boolean true if successful