AccumulatorV2

The base class for accumulators, that can accumulate inputs of type IN, and produce output of type OUT.

OUT should be a type that can be read atomically (e.g., Int, Long), or thread-safely (e.g., synchronized collections) because it will be read from other threads.

Source: AccumulatorV2.scala

Linear Supertypes

Serializable, Serializable, AnyRef, Any

Known Subclasses

CollectionAccumulator, DoubleAccumulator, LegacyAccumulatorWrapper, LongAccumulator

Instance Constructors

new AccumulatorV2()

Abstract Value Members

abstract def add(v: IN): Unit

Takes the inputs and accumulates.
abstract def copy(): AccumulatorV2[IN, OUT]

Creates a new copy of this accumulator.
abstract def isZero: Boolean

Returns if this accumulator is zero value or not.
Returns if this accumulator is zero value or not. e.g. for a counter accumulator, 0 is zero value; for a list accumulator, Nil is zero value.
abstract def merge(other: AccumulatorV2[IN, OUT]): Unit

Merges another same-type accumulator into this one and update its state, i.e.
Merges another same-type accumulator into this one and update its state, i.e. this should be merge-in-place.
abstract def reset(): Unit

Resets this accumulator, which is zero value.
Resets this accumulator, which is zero value. i.e. call isZero must return true.
abstract def value: OUT

Defines the current value of this accumulator

Concrete Value Members

final def !=(arg0: Any): Boolean

Definition Classes
AnyRef → Any
final def ##(): Int

Definition Classes
AnyRef → Any
final def ==(arg0: Any): Boolean

Definition Classes
AnyRef → Any
final def asInstanceOf[T0]: T0

Definition Classes
Any
def clone(): AnyRef

Attributes
protected[java.lang]
Definition Classes
AnyRef
Annotations
@throws( ... )
def copyAndReset(): AccumulatorV2[IN, OUT]

Creates a new copy of this accumulator, which is zero value.
Creates a new copy of this accumulator, which is zero value. i.e. call isZero on the copy must return true.
final def eq(arg0: AnyRef): Boolean

Definition Classes
AnyRef
def equals(arg0: Any): Boolean

Definition Classes
AnyRef → Any
def finalize(): Unit

Attributes
protected[java.lang]
Definition Classes
AnyRef
Annotations
@throws( classOf[java.lang.Throwable] )
final def getClass(): Class[_]

Definition Classes
AnyRef → Any
def hashCode(): Int

Definition Classes
AnyRef → Any
final def id: Long

Returns the id of this accumulator, can only be called after registration.
final def isInstanceOf[T0]: Boolean

Definition Classes
Any
final def isRegistered: Boolean

Returns true if this accumulator has been registered.
Returns true if this accumulator has been registered.

Note
All accumulators must be registered before use, or it will throw exception.
final def name: Option[String]

Returns the name of this accumulator, can only be called after registration.
final def ne(arg0: AnyRef): Boolean

Definition Classes
AnyRef
final def notify(): Unit

Definition Classes
AnyRef
final def notifyAll(): Unit

Definition Classes
AnyRef
final def synchronized[T0](arg0: ⇒ T0): T0

Definition Classes
AnyRef
def toString(): String

Definition Classes
AccumulatorV2 → AnyRef → Any
final def wait(): Unit

Definition Classes
AnyRef
Annotations
@throws( ... )
final def wait(arg0: Long, arg1: Int): Unit

Definition Classes
AnyRef
Annotations
@throws( ... )
final def wait(arg0: Long): Unit

Definition Classes
AnyRef
Annotations
@throws( ... )
final def writeReplace(): Any

Attributes
protected

Related Doc: package util

abstract class AccumulatorV2[IN, OUT] extends Serializable

Instance Constructors

new AccumulatorV2()

Abstract Value Members

abstract def add(v: IN): Unit

abstract def copy(): AccumulatorV2[IN, OUT]

abstract def isZero: Boolean

abstract def merge(other: AccumulatorV2[IN, OUT]): Unit

abstract def reset(): Unit

abstract def value: OUT

Concrete Value Members

final def !=(arg0: Any): Boolean

final def ##(): Int

final def ==(arg0: Any): Boolean

final def asInstanceOf[T0]: T0

def clone(): AnyRef

def copyAndReset(): AccumulatorV2[IN, OUT]

final def eq(arg0: AnyRef): Boolean

def equals(arg0: Any): Boolean

def finalize(): Unit

final def getClass(): Class[_]

def hashCode(): Int

final def id: Long

final def isInstanceOf[T0]: Boolean

final def isRegistered: Boolean

final def name: Option[String]

final def ne(arg0: AnyRef): Boolean

final def notify(): Unit

final def notifyAll(): Unit

final def synchronized[T0](arg0: ⇒ T0): T0

def toString(): String

final def wait(): Unit

final def wait(arg0: Long, arg1: Int): Unit

final def wait(arg0: Long): Unit

final def writeReplace(): Any

Inherited from Serializable

Inherited from Serializable

Inherited from AnyRef

Inherited from Any

Ungrouped