akka.stream

Class TransformerLike<T,U>

java.lang.Object

akka.stream.TransformerLike<T,U>

public abstract class TransformerLike<T,U>
extends java.lang.Object

Constructor Summary

Constructors

Constructor and Description
TransformerLike()

Method Summary

Modifier and Type	Method and Description
void	cleanup() Invoked after normal completion or failure.
boolean	isComplete() Invoked after handing off the elements produced from one input element to the downstream subscribers to determine whether to end stream processing at this point; in that case the upstream subscription is canceled.
void	onError(java.lang.Throwable cause) Invoked when failure is signaled from upstream.
abstract scala.collection.immutable.Seq<U>	onNext(T element) Invoked for each element to produce a (possibly empty) sequence of output elements.
scala.collection.immutable.Seq<U>	onTermination(scala.Option<java.lang.Throwable> e) Invoked before the Transformer terminates (either normal completion or after an onError) to produce a (possibly empty) sequence of elements in response to the end-of-stream event.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

TransformerLike

public TransformerLike()

Method Detail

onNext

public abstract scala.collection.immutable.Seq<U> onNext(T element)

Invoked for each element to produce a (possibly empty) sequence of output elements.

Parameters:

element - (undocumented)

Returns:

(undocumented)

isComplete

public boolean isComplete()

Invoked after handing off the elements produced from one input element to the downstream subscribers to determine whether to end stream processing at this point; in that case the upstream subscription is canceled.

Returns:

(undocumented)

onTermination

public scala.collection.immutable.Seq<U> onTermination(scala.Option<java.lang.Throwable> e)

Invoked before the Transformer terminates (either normal completion or after an onError) to produce a (possibly empty) sequence of elements in response to the end-of-stream event.

This method is only called if onError(java.lang.Throwable) does not throw an exception. The default implementation of onError(java.lang.Throwable) throws the received cause forcing the failure to propagate downstream immediately.

Parameters:

e - Contains a non-empty option with the error causing the termination or an empty option if the Transformer was completed normally

Returns:

(undocumented)

onError

public void onError(java.lang.Throwable cause)

Invoked when failure is signaled from upstream. If this method throws an exception, then onError is immediately propagated downstream. If this method completes normally then onTermination(scala.Option<java.lang.Throwable>) is invoked as a final step, passing the original cause.

Parameters:

cause - (undocumented)

cleanup

public void cleanup()

Invoked after normal completion or failure.