VirtualPublisher

java.lang.Object
- java.util.concurrent.atomic.AtomicReference<java.lang.Object>
- - akka.stream.impl.VirtualPublisher<T>

All Implemented Interfaces:

java.io.Serializable, org.reactivestreams.Publisher<T>
```
public class VirtualPublisher<T>
extends java.util.concurrent.atomic.AtomicReference<java.lang.Object>
implements org.reactivestreams.Publisher<T>
```
INTERNAL API
The implementation of Sink.asPublisher needs to offer a Publisher that defers to the upstream that is connected during materialization. This would be trivial if it were not for materialized value computations that may even spawn the code that does pub.subscribe(sub) in a Future, running concurrently with the actual materialization. Therefore we implement a minimal shell here that plugs the downstream and the upstream together as soon as both are known. Using a VirtualProcessor would technically also work, but it would defeat the purpose of subscription timeouts—the subscription would always already be established from the Actor’s perspective, regardless of whether a downstream will ever be connected.
One important consideration is that this Publisher must not retain a reference to the Subscriber after having hooked it up with the real Publisher, hence the use of Inert.subscriber as a tombstone.

See Also:

Serialized Form

Constructor Summary

Constructors
Constructor Description

VirtualPublisher()

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`registerPublisher(org.reactivestreams.Publisher<?> pub)`
`void`	`subscribe(org.reactivestreams.Subscriber<? super T> subscriber)`
`java.lang.String`	`toString()`

Methods inherited from class java.util.concurrent.atomic.AtomicReference
accumulateAndGet, compareAndExchange, compareAndExchangeAcquire, compareAndExchangeRelease, compareAndSet, get, getAcquire, getAndAccumulate, getAndSet, getAndUpdate, getOpaque, getPlain, lazySet, set, setOpaque, setPlain, setRelease, updateAndGet, weakCompareAndSet, weakCompareAndSetAcquire, weakCompareAndSetPlain, weakCompareAndSetRelease, weakCompareAndSetVolatile

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Constructor Detail
  - VirtualPublisher
```
public VirtualPublisher()
```
- Method Detail
  - registerPublisher
```
public final void registerPublisher(org.reactivestreams.Publisher<?> pub)
```
  - subscribe
```
public void subscribe(org.reactivestreams.Subscriber<? super T> subscriber)
```
    Specified by:
    
    subscribe in interface org.reactivestreams.Publisher<T>
  - toString
```
public java.lang.String toString()
```
    Overrides:
    
    toString in class java.util.concurrent.atomic.AtomicReference<java.lang.Object>