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LongAccumulator Class

Definition

One or more variables that together maintain a running long value updated using a supplied function.

[Android.Runtime.Register("java/util/concurrent/atomic/LongAccumulator", ApiSince=24, DoNotGenerateAcw=true)]
public class LongAccumulator : Java.Lang.Number, IDisposable, Java.Interop.IJavaPeerable
[<Android.Runtime.Register("java/util/concurrent/atomic/LongAccumulator", ApiSince=24, DoNotGenerateAcw=true)>]
type LongAccumulator = class
    inherit Number
    interface ISerializable
    interface IJavaObject
    interface IDisposable
    interface IJavaPeerable
Inheritance
LongAccumulator
Attributes
Implements

Remarks

One or more variables that together maintain a running long value updated using a supplied function. When updates (method #accumulate) are contended across threads, the set of variables may grow dynamically to reduce contention. Method #get (or, equivalently, #longValue) returns the current value across the variables maintaining updates.

This class is usually preferable to AtomicLong when multiple threads update a common value that is used for purposes such as collecting statistics, not for fine-grained synchronization control. Under low update contention, the two classes have similar characteristics. But under high contention, expected throughput of this class is significantly higher, at the expense of higher space consumption.

The order of accumulation within or across threads is not guaranteed and cannot be depended upon, so this class is only applicable to functions for which the order of accumulation does not matter. The supplied accumulator function should be side-effect-free, since it may be re-applied when attempted updates fail due to contention among threads. For predictable results, the accumulator function should be associative and commutative. The function is applied with an existing value (or identity) as one argument, and a given update as the other argument. For example, to maintain a running maximum value, you could supply Long::max along with Long.MIN_VALUE as the identity.

Class LongAdder provides analogs of the functionality of this class for the common special case of maintaining counts and sums. The call new LongAdder() is equivalent to new LongAccumulator((x, y) -> x + y, 0L).

This class extends Number, but does <em>not</em> define methods such as equals, hashCode and compareTo because instances are expected to be mutated, and so are not useful as collection keys.

Added in 1.8.

Java documentation for java.util.concurrent.atomic.LongAccumulator.

Portions of this page are modifications based on work created and shared by the Android Open Source Project and used according to terms described in the Creative Commons 2.5 Attribution License.

Constructors

LongAccumulator(ILongBinaryOperator, Int64)

Creates a new instance using the given accumulator function and identity element.

LongAccumulator(IntPtr, JniHandleOwnership)

Properties

Class

Returns the runtime class of this Object.

(Inherited from Object)
Handle

The handle to the underlying Android instance.

(Inherited from Object)
JniIdentityHashCode (Inherited from Object)
JniPeerMembers
PeerReference (Inherited from Object)
ThenReset

Equivalent in effect to #get followed by #reset.

ThresholdClass
ThresholdType

Methods

Accumulate(Int64)

Updates with the given value.

ByteValue()

Returns the value of the specified number as a byte.

(Inherited from Number)
Clone()

Creates and returns a copy of this object.

(Inherited from Object)
Dispose() (Inherited from Object)
Dispose(Boolean) (Inherited from Object)
DoubleValue()

Returns the #get current value as a double after a widening primitive conversion.

Equals(Object)

Indicates whether some other object is "equal to" this one.

(Inherited from Object)
FloatValue()

Returns the #get current value as a float after a widening primitive conversion.

Get()

Returns the current value.

GetHashCode()

Returns a hash code value for the object.

(Inherited from Object)
IntValue()

Returns the #get current value as an int after a narrowing primitive conversion.

JavaFinalize()

Called by the garbage collector on an object when garbage collection determines that there are no more references to the object.

(Inherited from Object)
LongValue()

Equivalent to #get.

Notify()

Wakes up a single thread that is waiting on this object's monitor.

(Inherited from Object)
NotifyAll()

Wakes up all threads that are waiting on this object's monitor.

(Inherited from Object)
Reset()

Resets variables maintaining updates to the identity value.

SetHandle(IntPtr, JniHandleOwnership)

Sets the Handle property.

(Inherited from Object)
ShortValue()

Returns the value of the specified number as a short.

(Inherited from Number)
ToArray<T>() (Inherited from Object)
ToString()

Returns a string representation of the object.

(Inherited from Object)
UnregisterFromRuntime() (Inherited from Object)
Wait()

Causes the current thread to wait until it is awakened, typically by being <em>notified</em> or <em>interrupted</em>.

(Inherited from Object)
Wait(Int64, Int32)

Causes the current thread to wait until it is awakened, typically by being <em>notified</em> or <em>interrupted</em>, or until a certain amount of real time has elapsed.

(Inherited from Object)
Wait(Int64)

Causes the current thread to wait until it is awakened, typically by being <em>notified</em> or <em>interrupted</em>, or until a certain amount of real time has elapsed.

(Inherited from Object)

Explicit Interface Implementations

IJavaPeerable.Disposed() (Inherited from Object)
IJavaPeerable.DisposeUnlessReferenced() (Inherited from Object)
IJavaPeerable.Finalized() (Inherited from Object)
IJavaPeerable.JniManagedPeerState (Inherited from Object)
IJavaPeerable.SetJniIdentityHashCode(Int32) (Inherited from Object)
IJavaPeerable.SetJniManagedPeerState(JniManagedPeerStates) (Inherited from Object)
IJavaPeerable.SetPeerReference(JniObjectReference) (Inherited from Object)

Extension Methods

JavaCast<TResult>(IJavaObject)

Performs an Android runtime-checked type conversion.

JavaCast<TResult>(IJavaObject)
GetJniTypeName(IJavaPeerable)

Applies to