LongAdder Class

Reference

Definition

Namespace:: Java.Util.Concurrent.Atomic

Assembly:: Mono.Android.dll

Important

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One or more variables that together maintain an initially zero long sum.

[Android.Runtime.Register("java/util/concurrent/atomic/LongAdder", ApiSince=24, DoNotGenerateAcw=true)]
public class LongAdder : Java.Lang.Number, IDisposable, Java.Interop.IJavaPeerable

[<Android.Runtime.Register("java/util/concurrent/atomic/LongAdder", ApiSince=24, DoNotGenerateAcw=true)>]
type LongAdder = class
    inherit Number
    interface ISerializable
    interface IJavaObject
    interface IDisposable
    interface IJavaPeerable

Inheritance: Object

Object

Number
LongAdder

Attributes: RegisterAttribute

Implements: IJavaObject IJavaPeerable ISerializable IDisposable

Remarks

One or more variables that together maintain an initially zero long sum. When updates (method #add) are contended across threads, the set of variables may grow dynamically to reduce contention. Method #sum (or, equivalently, #longValue) returns the current total combined across the variables maintaining the sum.

This class is usually preferable to AtomicLong when multiple threads update a common sum 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.

LongAdders can be used with a java.util.concurrent.ConcurrentHashMap to maintain a scalable frequency map (a form of histogram or multiset). For example, to add a count to a ConcurrentHashMap<String,LongAdder> freqs, initializing if not already present, you can use freqs.computeIfAbsent(key, k -> new LongAdder()).increment();

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.LongAdder.

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

LongAdder()	Creates a new adder with initial sum of zero.
LongAdder(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)
ThresholdClass
ThresholdType

Methods

Add(Int64)	Adds 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)
Decrement()	Equivalent to `add(-1)`.
Dispose()	(Inherited from Object)
Dispose(Boolean)	(Inherited from Object)
DoubleValue()	Returns the `#sum` 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 `#sum` as a `float` after a widening primitive conversion.
GetHashCode()	Returns a hash code value for the object. (Inherited from Object)
Increment()	Equivalent to `add(1)`.
IntValue()	Returns the `#sum` 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 `#sum`.
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 the sum to zero.
SetHandle(IntPtr, JniHandleOwnership)	Sets the Handle property. (Inherited from Object)
ShortValue()	Returns the value of the specified number as a `short`. (Inherited from Number)
Sum()	Returns the current sum.
SumThenReset()	Equivalent in effect to `#sum` followed by `#reset`.
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

次の方法で共有