Flow

Value Members

final def !=(arg0: Any): Boolean

Definition Classes
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final def ##(): Int

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final def ==(arg0: Any): Boolean

Definition Classes
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final def asInstanceOf[T0]: T0

Definition Classes
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def clone(): AnyRef

Attributes
protected[java.lang]
Definition Classes
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Annotations
@throws( ... )
def create[T](): Flow[T, T, NotUsed]

Create a Flow which can process elements of type T.
final def eq(arg0: AnyRef): Boolean

Definition Classes
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def equals(arg0: Any): Boolean

Definition Classes
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def finalize(): Unit

Attributes
protected[java.lang]
Definition Classes
AnyRef
Annotations
@throws( classOf[java.lang.Throwable] )
def fromFunction[I, O](f: Function[I, O]): Flow[I, O, NotUsed]

Creates a [Flow] which will use the given function to transform its inputs to outputs.
Creates a [Flow] which will use the given function to transform its inputs to outputs. It is equivalent to Flow.create[T].map(f)
def fromGraph[I, O, M](g: Graph[FlowShape[I, O], M]): Flow[I, O, M]

A graph with the shape of a flow logically is a flow, this method makes it so also in type.
def fromProcessor[I, O](processorFactory: Creator[Processor[I, O]]): Flow[I, O, NotUsed]
def fromProcessorMat[I, O, Mat](processorFactory: Creator[Pair[Processor[I, O], Mat]]): Flow[I, O, Mat]
def fromSinkAndSource[I, O](sink: Graph[SinkShape[I], _], source: Graph[SourceShape[O], _]): Flow[I, O, NotUsed]

Creates a Flow from a Sink and a Source where the Flow's input will be sent to the Sink and the Flow's output will come from the Source.
Creates a Flow from a Sink and a Source where the Flow's input will be sent to the Sink and the Flow's output will come from the Source.
The resulting flow can be visualized as:
```
    +----------------------------------------------+
    | Resulting Flow[I, O, NotUsed]                |
    |                                              |
    |  +---------+                  +-----------+  |
    |  |         |                  |           |  |
I  ~~> | Sink[I] | [no-connection!] | Source[O] | ~~> O
    |  |         |                  |           |  |
    |  +---------+                  +-----------+  |
    +----------------------------------------------+
```
The completion of the Sink and Source sides of a Flow constructed using this method are independent. So if the Sink receives a completion signal, the Source side will remain unaware of that. If you are looking to couple the termination signals of the two sides use Flow.fromSinkAndSourceCoupled instead.
See also fromSinkAndSourceMat when access to materialized values of the parameters is needed.

def fromSinkAndSourceCoupled[I, O](sink: Graph[SinkShape[I], _], source: Graph[SourceShape[O], _]): Flow[I, O, NotUsed]

Allows coupling termination (cancellation, completion, erroring) of Sinks and Sources while creating a Flow from them.

Allows coupling termination (cancellation, completion, erroring) of Sinks and Sources while creating a Flow from them. Similar to Flow.fromSinkAndSource however couples the termination of these two operators.

The resulting flow can be visualized as:

    +---------------------------------------------+
    | Resulting Flow[I, O, NotUsed]               |
    |                                             |
    |  +---------+                 +-----------+  |
    |  |         |                 |           |  |
I  ~~> | Sink[I] | ~~~(coupled)~~~ | Source[O] | ~~> O
    |  |         |                 |           |  |
    |  +---------+                 +-----------+  |
    +---------------------------------------------+

E.g. if the emitted Flow gets a cancellation, the Source of course is cancelled, however the Sink will also be completed. The table below illustrates the effects in detail:

Returned Flow	Sink (`in`)	Source (`out`)
cause: upstream (sink-side) receives completion	effect: receives completion	effect: receives cancel
cause: upstream (sink-side) receives error	effect: receives error	effect: receives cancel
cause: downstream (source-side) receives cancel	effect: completes	effect: receives cancel
effect: cancels upstream, completes downstream	effect: completes	cause: signals complete
effect: cancels upstream, errors downstream	effect: receives error	cause: signals error or throws
effect: cancels upstream, completes downstream	cause: cancels	effect: receives cancel

See also fromSinkAndSourceCoupledMat when access to materialized values of the parameters is needed.

def fromSinkAndSourceCoupledMat[I, O, M1, M2, M](sink: Graph[SinkShape[I], M1], source: Graph[SourceShape[O], M2], combine: Function2[M1, M2, M]): Flow[I, O, M]

Allows coupling termination (cancellation, completion, erroring) of Sinks and Sources while creating a Flow from them.
Allows coupling termination (cancellation, completion, erroring) of Sinks and Sources while creating a Flow from them. Similar to Flow.fromSinkAndSource however couples the termination of these two operators.
The resulting flow can be visualized as:
```
    +-----------------------------------------------------+
    | Resulting Flow[I, O, M]                             |
    |                                                     |
    |  +-------------+                 +---------------+  |
    |  |             |                 |               |  |
I  ~~> | Sink[I, M1] | ~~~(coupled)~~~ | Source[O, M2] | ~~> O
    |  |             |                 |               |  |
    |  +-------------+                 +---------------+  |
    +-----------------------------------------------------+
```
E.g. if the emitted Flow gets a cancellation, the Source of course is cancelled, however the Sink will also be completed. The table on Flow.fromSinkAndSourceCoupled illustrates the effects in detail.
The combine function is used to compose the materialized values of the sink and source into the materialized value of the resulting Flow.
def fromSinkAndSourceMat[I, O, M1, M2, M](sink: Graph[SinkShape[I], M1], source: Graph[SourceShape[O], M2], combine: Function2[M1, M2, M]): Flow[I, O, M]

Creates a Flow from a Sink and a Source where the Flow's input will be sent to the Sink and the Flow's output will come from the Source.
Creates a Flow from a Sink and a Source where the Flow's input will be sent to the Sink and the Flow's output will come from the Source.
The resulting flow can be visualized as:
```
    +-------------------------------------------------------+
    | Resulting Flow[I, O, M]                              |
    |                                                      |
    |  +-------------+                  +---------------+  |
    |  |             |                  |               |  |
I  ~~> | Sink[I, M1] | [no-connection!] | Source[O, M2] | ~~> O
    |  |             |                  |               |  |
    |  +-------------+                  +---------------+  |
    +------------------------------------------------------+
```
The completion of the Sink and Source sides of a Flow constructed using this method are independent. So if the Sink receives a completion signal, the Source side will remain unaware of that. If you are looking to couple the termination signals of the two sides use Flow.fromSinkAndSourceCoupledMat instead.
The combine function is used to compose the materialized values of the sink and source into the materialized value of the resulting Flow.
final def getClass(): Class[_]

Definition Classes
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def hashCode(): Int

Definition Classes
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final def isInstanceOf[T0]: Boolean

Definition Classes
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def lazyInitAsync[I, O, M](flowFactory: Creator[CompletionStage[Flow[I, O, M]]]): Flow[I, O, CompletionStage[Optional[M]]]

Creates a real Flow upon receiving the first element.
Creates a real Flow upon receiving the first element. Internal Flow will not be created if there are no elements, because of completion, cancellation, or error.
The materialized value of the Flow is a Future[Option[M]] that is completed with Some(mat) when the internal flow gets materialized or with None when there where no elements. If the flow materialization (including the call of the flowFactory) fails then the future is completed with a failure.
Emits when the internal flow is successfully created and it emits
Backpressures when the internal flow is successfully created and it backpressures
Completes when upstream completes and all elements have been emitted from the internal flow
Cancels when downstream cancels
final def ne(arg0: AnyRef): Boolean

Definition Classes
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final def notify(): Unit

Definition Classes
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final def notifyAll(): Unit

Definition Classes
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def of[T](clazz: Class[T]): Flow[T, T, NotUsed]

Create a Flow which can process elements of type T.
final def synchronized[T0](arg0: ⇒ T0): T0

Definition Classes
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def toString(): String

Definition Classes
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def upcast[In, SuperOut, Out <: SuperOut, M](flow: Flow[In, Out, M]): Flow[In, SuperOut, M]

Upcast a stream of elements to a stream of supertypes of that element.
Upcast a stream of elements to a stream of supertypes of that element. Useful in combination with fan-in operators where you do not want to pay the cost of casting each element in a map.
SuperOut
a supertype to the type of element flowing out of the flow
returns
A flow that accepts In and outputs elements of the super type
final def wait(): Unit

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

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

Definition Classes
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Annotations
@throws( ... )

Deprecated Value Members

def lazyInit[I, O, M](flowFactory: Function[I, CompletionStage[Flow[I, O, M]]], fallback: Creator[M]): Flow[I, O, M]

Creates a real Flow upon receiving the first element.
Creates a real Flow upon receiving the first element. Internal Flow will not be created if there are no elements, because of completion, cancellation, or error.
The materialized value of the Flow is the value that is created by the fallback function.
Emits when the internal flow is successfully created and it emits
Backpressures when the internal flow is successfully created and it backpressures
Completes when upstream completes and all elements have been emitted from the internal flow
Cancels when downstream cancels

Annotations
@Deprecated @deprecated
Deprecated
(Since version 2.5.12) Use lazyInitAsync instead. (lazyInitAsync returns a flow with a more useful materialized value.)

Related Docs: class Flow | package javadsl

object Flow

Value Members

final def !=(arg0: Any): Boolean

final def ##(): Int

final def ==(arg0: Any): Boolean

final def asInstanceOf[T0]: T0

def clone(): AnyRef

def create[T](): Flow[T, T, NotUsed]

final def eq(arg0: AnyRef): Boolean

def equals(arg0: Any): Boolean

def finalize(): Unit

def fromFunction[I, O](f: Function[I, O]): Flow[I, O, NotUsed]

def fromGraph[I, O, M](g: Graph[FlowShape[I, O], M]): Flow[I, O, M]

def fromProcessor[I, O](processorFactory: Creator[Processor[I, O]]): Flow[I, O, NotUsed]

def fromProcessorMat[I, O, Mat](processorFactory: Creator[Pair[Processor[I, O], Mat]]): Flow[I, O, Mat]

def fromSinkAndSource[I, O](sink: Graph[SinkShape[I], _], source: Graph[SourceShape[O], _]): Flow[I, O, NotUsed]

def fromSinkAndSourceCoupled[I, O](sink: Graph[SinkShape[I], _], source: Graph[SourceShape[O], _]): Flow[I, O, NotUsed]

def fromSinkAndSourceCoupledMat[I, O, M1, M2, M](sink: Graph[SinkShape[I], M1], source: Graph[SourceShape[O], M2], combine: Function2[M1, M2, M]): Flow[I, O, M]

def fromSinkAndSourceMat[I, O, M1, M2, M](sink: Graph[SinkShape[I], M1], source: Graph[SourceShape[O], M2], combine: Function2[M1, M2, M]): Flow[I, O, M]

final def getClass(): Class[_]

def hashCode(): Int

final def isInstanceOf[T0]: Boolean

def lazyInitAsync[I, O, M](flowFactory: Creator[CompletionStage[Flow[I, O, M]]]): Flow[I, O, CompletionStage[Optional[M]]]

final def ne(arg0: AnyRef): Boolean

final def notify(): Unit

final def notifyAll(): Unit

def of[T](clazz: Class[T]): Flow[T, T, NotUsed]

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

def toString(): String

def upcast[In, SuperOut, Out <: SuperOut, M](flow: Flow[In, Out, M]): Flow[In, SuperOut, M]

final def wait(): Unit

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

final def wait(arg0: Long): Unit

Deprecated Value Members

def lazyInit[I, O, M](flowFactory: Function[I, CompletionStage[Flow[I, O, M]]], fallback: Creator[M]): Flow[I, O, M]

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